Evolution trend of soil fertility in tobacco-planting area of Chenzhou, Hunan Province, China
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Yansong Xiao
, Yahua Liao , Jianlin Hou , Lijuan Li , Taosha Xu , Fengying Ma , Fahui Yu , Zhipeng Tan , Zhihong He , Hong Jian , Hongguang Li and Bin He
Abstract
In this study, the data of fertility indicators of soil samples (0–20 cm) in 1980s, 2000 and 2015 in Chenzhou city were used, and the soil integrated fertility index (IFI) was calculated. The results showed that the soil pH was decreased, total nitrogen (TN), organic matter (OM), available phosphorus (AP) and potassium (AK), exchangeable calcium (Ca2+), magnesium (Mg2+) and available copper (Cu) contents were increased, total phosphorus (TP), available sulfur (S) and water-soluble chlorine (Cl−) contents were decreased, total potassium (TK), available boron (B), iron (Fe), manganese (Mn) and zinc (Zn) were decreased first and then increased. In 2015, most of the fields were higher in pH, OM, TN, AN, AK, Ca2+, Mg2+, S, Fe, Mn, Cu and Zn, suitable in B, but lower in TP, AP, TK, available molybdenum (Mo) and Cl−. Most of the fields were in the middle grade of IFI in 2000 and 2015, and the mean IFI increased from 0.492 to 0.556 from 2000 to 2015. Thus, for soil improvement, more attention should be paid to adjust soil pH, reduce the application of organic, nitrogen and calcium fertilizers, while increase the fertilizer application of other nutrients.
1 Introduction
Soil fertility influences the growth, yield and quality of tobacco [1,2,3,4,5], which is continuously concerned in China. So far, lots of studies have been conducted with many literature studies published on fertility evaluation of tobacco-planting soil; for example, more than 300 literature studies in Chinese could be retrieved by the title or keywords of “tobacco,” “fertility” and “evaluation” in the China National Knowledge Infrastructure (www.dlib.cnki.net/), which almost covered all the tobacco-planting regions in China and at various scales of province, city and county.
Tobacco usually is planted in the drylands with sandy soil texture, but in many areas of southern China, such as Guangdong, Fujian, Jiangxi, Guangxi and south Hunan and Anhui, it is very common that tobacco is planted in rice fields in the high ridge form (no matter what kind of soil texture) and rotated with late rice. Chenzhou city, with a long history of tobacco-planting as early as in 1,593 and where most paddy fields are under tobacco–rice rotation [6], is the most important and typical planting region of flue-cured tobacco with burnt-pure sweet aroma in China [7]. The area of tobacco-planting in Chenzhou is about 2.67 × 104 hm2 in recent years, which plays an important role in ensuring the high-quality raw materials supply of the tobacco industry and the local social and economic sustainable development.
Some literature studies were published about tobacco-planting soil nutrient status in Guizhou [8,9,10,11], which played an important guiding role in improving the soil fertility and quality of tobacco-planting fields. However, there are limited fertility indicators (e.g., pH, organic matter (OM), total nitrogen (TN) and available boron) were involved in the above-mentioned studies, and so far, there are few reports reflecting the changes in soil fertility [9]. Two questions are still unclear and should be answered which are concerned with the influences of tobacco-planting on soil fertility: (1) does tobacco-planting really can improve soil fertility? if so, by how much? Also, a new round of tobacco-planting soil improvement is underway in China; it is urgent and helpful to know the status and evolution of soil fertility; therefore, this study was conducted in order to quantitatively analyze the soil fertility of tobacco-planting fields in Chenzhou in order to provide further scientific guidance for fertilization and soil improvement for tobacco-planting in Chenzhou.
2 Materials and methods
2.1 Data sources of soil fertility indicators
The data of soil fertility indicators used in this study came from three periods, the 2nd national soil survey conducted in the 1980s [12], and tobacco-planting soil surveys conducted in 2000 and 2015, which included 350, 746 and 1,055 soil samples, respectively. The obtained data of the 1980s were the statistic information of all soil samples, and no data of each sample is available.
According to the historical records, the soil sample of the plough layer in each field was collected randomly at 5–8 points with stainless steel soil drill and then mixed completely. The measured soil properties (soil fertility indicators) included OM, TN, total phosphorous (TP), total potassium (TK), available nitrogen (AN), available phosphorous (AP), available potassium (AK), available boron (B), available iron (Fe), available manganese (Mn), available copper (Cu), available zinc (Zn) and available molybdenum (Mo) for all soil samples in the three periods, and pH (H2O), exchangeable calcium (Ca2+), exchangeable magnesium (Mg2+), available sulfur (S), and water-soluble chlorine (Cl−) for the soil samples in 2000 and 2015. The detailed determination methods for soil fertility indicators could be found in related literature studies [13,14].
2.2 Quantitative assessment of soil fertility
There are various methods for the assessment of soil fertility; in this study, soil integrated fertility index (IFI) was used to evaluate soil fertility, and IFI was calculated with the fuzzy mathematics method [15]; first, the membership function types and inflection points of indicators were determined; second, the membership values of the indicators were calculated; third, the weights of the indicators were determined, and finally, IFI was calculated for soil samples according to the following formula:
where W i stands for the weight of indicator i and N i for the membership value of indicator i. IFI is ranged from 0 to 1. The higher the IFI value, the higher the soil fertility. Generally, IFI is divided into five grades according to the equidistant method [16,17]: ≥0.80 (higher), 0.6–0.8 (high), 0.4–0.6 (Middle), 0.2–0.4 (low) and <0.2 (lower).
2.2.1 Grading standards of fertility indicators
There are many reports available in China on the grading standards of soil fertility indicators for tobacco-planting fields. In this study, the indicators were divided into 4 or 5 grades as in Table 1 based on the actual situation of tobacco-planting soils in Hunan Province [18,19] and the corresponding grading of tobacco-planting soils in neighboring areas of Hunan Province [20,21,22,23,24,25,26].
Grading standards of soil fertility indicators for tobacco-planting fields
| Fertility indicator | Grade | ||||
|---|---|---|---|---|---|
| Very low | Low | Suitable | High | Very high | |
| pH | <5.0 | 5.0–5.5 | 5.5–7.0 | 7.0–7.5 | ≥7.5 |
| SOM | <10 | 10–15 | 15–30 | 30–40 | ≥40 |
| TN | <0.5 | 0.5–1 | 1–2 | 2–2.5 | ≥2.5 |
| AN | <65 | 65–100 | 100–180 | 180–240 | ≥240 |
| TP | <0.5 | 0.5–1 | 1–1.5 | ≥1.5 | |
| AP | <10 | 10–15 | 15–30 | 30–40 | ≥40 |
| TK | <10 | 10–15 | 15–20 | 20–25 | ≥25 |
| AK | <80 | 80–150 | 150–220 | 220–350 | ≥350 |
| Ca2+ | <3 | 3–6 | 6–10 | 10–18 | ≥18 |
| Mg2+ | <0.5 | 0.5–1.0 | 1.0–1.6 | 1.6–3.2 | ≥3.2 |
| S | <10 | 10–16 | 16–30 | 30–50 | ≥50 |
| B | <0.15 | 0.15–0.3 | 0.3–0.6 | 0.6–1.0 | ≥1.0 |
| Fe | <2.5 | 2.5–4.5 | 4.5–10 | 10–60 | ≥60 |
| Mn | <5 | 5–10 | 10–20 | 20–40 | ≥40 |
| Cu | <0.2 | 0.2–0.5 | 0.5–1.0 | 1.0–3.0 | ≥3.0 |
| Zn | <0.5 | 0.5–1.0 | 1.0–2.0 | 2.0–4.0 | ≥4.0 |
| Mo | <0.1 | 0.1–0.15 | 0.15–0.2 | 0.2–0.3 | ≥0.3 |
| Cl− | <5 | 5–10 | 10–30 | 30–40 | ≥40 |
Notes: in the first column, SOM, TN, TP, TK, g/kg; AN, AP, AK, S, B, Fe, Mn, Cu, Zn, Mo, Cl−, mg/kg; Ca2+, cmol(1/2Ca2+)/kg; Mg2+, cmol(1/2Mg2+)/kg. The same is below.
2.2.2 Calculation of membership value of fertility indicator
The membership function types of the fertility indicators were determined according to their effects on the growth, yield and quality of tobacco, among which, pH, OM, TN, AN and Cl− were belonged to the parabolas type, while TP, AP, TK, AK, Ca, Mg, S, B, Fe, Mn, Cu, Zn and Mo belonged to the S type [15,27]. Combining with the actual situation of tobacco growing soils in Chenzhou [8,9,10,11,17], the turning points of membership function of each fertility indicator were determined according to expert experience and related literature studies published [5,16,17,18,19,22,26,28] (Table 2; x 1, lower limiting value; x 2, upper limiting value; x 3, lower optimal value; and x 4 , upper optimal value).
Membership function types and turning points of soil fertility indicators
| Fertility indicator | Membership function type | Lower limit, x 1 | Lower optimal, x 3 | Upper optimal, x 4 | Upper limit, x 2 |
|---|---|---|---|---|---|
| pH | Parabolas | 5 | 5.5 | 7 | 8 |
| SOM | Parabolas | 15 | 20 | 35 | 45 |
| TN | Parabolas | 0.5 | 1 | 2 | 2.5 |
| AN | Parabolas | 65 | 100 | 180 | 240 |
| Cl− | Parabolas | 5 | 10 | 30 | 40 |
| TP | S | 0.5 | 1.5 | ||
| AP | S | 10 | 40 | ||
| TK | S | 10 | 25 | ||
| AK | S | 80 | 350 | ||
| Ca | S | 3 | 20 | ||
| Mg | S | 0.5 | 4 | ||
| S | S | 16 | 30 | ||
| B | S | 0.2 | 1.5 | ||
| Fe | S | 4.5 | 70 | ||
| Mn | S | 10 | 50 | ||
| Cu | S | 0.5 | 4 | ||
| Zn | S | 1 | 5 | ||
| Mo | S | 0.15 | 0.4 |
The membership functions of S-type and parabolic indicators were calculated as follows:
2.2.3 Determination of weights of indicators
The weights of indicators were determined by principal component analysis (PCA), which is commonly used in soil fertility and quality evaluation [21,29,30]. In order to avoid the appearance of a negative value in weight, the measured values of pH, OM, TN, TP, TK, AN, AP, AK, AS, Ca, Mg, S, B, Fe, Cu, Zn, Mo and Cl−1 were standardized using Z-score standardization method, while those of Mn were standardized using the negative range normalization method in SPSS software [31,32]. The KMO test coefficient obtained was 0.727, indicating that the data structure was good and the linear correlation between the data was satisfied, which could be used for principal component analysis, while the p value of Bartlett’s test was less than 0.001, rejecting the null hypothesis, indicating that the data could be extracted by principal components. The obtained weights of indicators are shown in Table 3, and the detailed routine for the acquisition of indicator weights was not listed here.
Weight values of soil fertility indicators for tobacco-planting fields in Chenzhou
| Indicator | pH | OM | TN | TP | TK | AN | AP | AK | Ca |
|---|---|---|---|---|---|---|---|---|---|
| Weight | 0.031 | 0.075 | 0.065 | 0.061 | 0.026 | 0.058 | 0.066 | 0.065 | 0.032 |
| Indicator | Mg | S | B | Fe | Mn | Cu | Zn | Mo | Cl |
| Weight | 0.039 | 0.072 | 0.067 | 0.014 | 0.017 | 0.115 | 0.114 | 0.044 | 0.039 |
2.3 Data processing and statistics
Microsoft Excel 2016 and IBM Statistics SPSS 22.0 software were used for the statistical analysis of the data, and Duncan test method (p < 0.05) was used for the analysis of variance and multiple comparisons [31,32].
3 Results
3.1 Statistics and comparison of soil fertility indicators
Table 4 shows the statistical results of the indicators in the three periods. From the average values of the indicators, it is shown in Table 3 that pH was reduced insignificantly from 7.18 in 2000 to 6.99 in 2015 (Sig. = 0.198, two-tailed, the same below). OM showed an increasing tendency between 1980s and 2015, which increased by 18.22% from 1980 to 2000 and significantly by 4.64% from 2000 to 2015 (Sig. = 0.008). TN also showed an increasing tendency between 1980 and 2015, which increased by 44.51% from 1980 to 2000 and insignificantly by 1.14% from 2000 to 2015 (Sig. = 0.680). TP showed a decreasing tendency from 1980 to 2015, decreased by 31.39% from the 1980s to 2000 and significantly by 2.13% from 2000 to 2015 (Sig. = 0.001). TK decreased first then increased within the 1980s–2015, decreased by 53.05% from the 1980s to 2000 and then increased significantly by 16.45% from 2000 to 2015 (Sig. = 0.000). AN increased first then decreased within the 1980s–2015, increased by 51.90% from 1980s to 2000 and then decreased significantly by 9.69% from 2000 to 2015 (Sig. = 0.000). AP and AK both showed an increasing tendency within 1980–and 2015, which increased by 216.85 and 57.64% from the 1980s to 2000 and significantly by 29.36 and 70.36% from 2000 to 2015 (Sig. = 0.000). Ca, Mg and Cu all showed an increasing tendency from 2000 to 2015, which increased significantly by 157.31%, 20.44 and 16.58% (Sigs. of Ca and Mg = 0.000, Sig. Cu = 0.003). S and Cl− both showed a decreasing tendency from 2000 to 2015, which decreased significantly by 24.08 and 65.00% (both Sigs. = 0.000). B, Fe, Mn and Zn all decreased first then increased within the 1980s–2015, decreased by 57.50, 17.87, 33.88 and 0.28% from 1980s to 2000 and then increased significantly by 223.53, 85.82, 34.52 and 23.68%, respectively, from 2000 to 2015 (Sigs. of B, Fe and Mn = 0.000, Sig. of Zn = 0.008). Mo showed a decreasing tendency within 1980–2015 and decreased by 16.00% and significantly by 23.81% (Sig. = 0.015).
Statistic information of soil fertility indicators in 2000 and 2015 in Chenzhou
| Indicators | 1980s (n = 350) | 2000 (n = 746) | 2015 (n = 1,055) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean ± S.D. | C.V. (%) | Grade | Mean ± S.D. | Grade | C.V. (%) | Skewness | Kurtosis | Mean ± S.D. | Grade | C.V. (%) | Skewness | Kurtosis | |
| pH | / | / | / | 7.18 ± 0.94a | High | 13.09 | −0.98 | −0.26 | 6.99 ± 0.93a | Suitable | 13.30 | −0.97 | −0.34 |
| OM | 38.8 ± 2.70 | 6.96 | High | 45.87 ± 13.98A | Very high | 30.48 | 0.03 | 0.03 | 48.00 ± 14.37B | Very high | 29.94 | 0.46 | 0.51 |
| TN | 1.82 ± 0.15 | 8.24 | Suitable | 2.63 ± 0.74a | Very high | 28.14 | 0.09 | −0.03 | 2.66 ± 0.71a | Very high | 26.69 | 0.89 | 1.40 |
| TP | 1.37 ± 0.17 | 12.41 | Suitable | 0.94 ± 0.29A | Low | 30.85 | 0.33 | 1.05 | 0.92 ± 0.28B | Low | 30.43 | 0.68 | 1.25 |
| TK | 23.30 ± 1.61 | 6.91 | High | 10.94 ± 2.99A | Low | 27.33 | 0.47 | 0.28 | 12.74 ± 3.83B | Low | 30.06 | 0.41 | 0.10 |
| AN | 147.97 ± 7.87 | 5.32 | Suitable | 224.76 ± 68.10A | High | 30.30 | 0.37 | 0.74 | 202.98 ± 54.04B | High | 26.62 | 0.32 | 1.78 |
| AP | 8.90 ± 1.00 | 11.24 | Very low | 28.20 ± 12.81A | Suitable | 45.43 | 1.73 | 11.17 | 36.48 ± 17.74B | High | 48.63 | 2.33 | 10.16 |
| AK | 76.60 ± 5.63 | 7.35 | Very low | 120.75 ± 60.02A | Low | 49.71 | 4.79 | 46.4 | 205.71 ± 87.47B | Suitable | 42.52 | 0.56 | 1.14 |
| Ca | / | / | / | 12.93 ± 5.77A | high | 44.62 | 0.86 | 1.27 | 33.27 ± 23.27B | very high | 69.94 | 8.26 | 107.76 |
| Mg | / | / | / | 1.37 ± 0.78A | Suitable | 56.93 | 0.88 | 0.89 | 1.65 ± 1.04B | High | 63.03 | 0.62 | −1.00 |
| S | / | / | / | 51.92 ± 24.48a | Very high | 47.15 | 1.57 | 6.91 | 39.42 ± 35.81b | High | 90.84 | 1.25 | 2.02 |
| B | 0.40 ± | / | Suitable | 0.17 ± 0.10A | Low | 58.82 | 1.58 | 6.75 | 0.55 ± 0.18B | Suitable | 32.73 | 1.23 | 1.23 |
| Fe | 93.61 ± | / | Very high | 76.88 ± 49.20A | Very high | 64.00 | 1.30 | 1.38 | 142.86 ± 89.55B | Very high | 62.68 | 2.94 | 12.37 |
| Mn | 37.37 ± | / | High | 24.71 ± 29.99A | high | 121.37 | 5.51 | 46.82 | 33.24 ± 31.52B | High | 94.83 | 12.66 | 190.18 |
| Cu | 3.74 ± | / | Very high | 4.36 ± 4.28A | very high | 119.22 | 13.81 | 240.83 | 4.70 ± 5.31B | Very high | 119.59 | 15.65 | 318.23 |
| Zn | 3.60 ± | / | High | 3.59 ± 5.37A | high | 123.17 | 8.12 | 85.72 | 4.44 ± 9.77B | Very high | 207.87 | 1.05 | 1.88 |
| Mo | 0.25± | / | High | 0.21 ± 0.28a | High | 133.33 | 9.95 | 156.99 | 0.16 ± 0.23b | Low | 143.75 | 8.18 | 124.05 |
| Cl− | / | / | / | 18.49 ± 10.34A | Suitable | 57.44 | 1.12 | 3.89 | 6.30 ± 9.84B | Low | 156.19 | 2.72 | 11.96 |
Note: (1) Data defaulted; (2) total sample numbers of Ca2+ and Mg2+ in 2000 is 314; (3) values in the same line followed by different uppercase or lowercase letters are significantly different at the 0.01 or 0.05 level: the same as below.
In the 1980s, OM, TN, TK, AN and AK belonged to the low variation (C.V. < 10%,), while TP and AP belonged to the moderate variation (C.V. = 10–100%). In 2000, pH, OM, TN, TP, TK, AN, AP, AK, Ca, Mg, S, B, Fe and Cl− belonged to moderate middle variation, while Mn, Cu, Zn and Mo belonged to the strong variation (C.V. > 100%). In 2015, pH, OM, TN, TP, TK, AN, AP, AK, Ca, Mg, S, B, Fe and Mn remained in the moderate middle variation, Cu, Zn and Mo remained in the strong variation (C.V. > 100%), while Cl− changed from the moderate variation to the strong one. It also can be seen from Table 4 that, in the values of C.V.s (%), pH, OM, TN, TP, TK, AN, AP, AK, Mg, Fe, Cu and Mo changed smaller (all lower than 15%), while Ca, S, Zn and Cl increased greatly (56.74, 92.67, 68.78 and 171.90%, respectively), and B and Mn decreased greatly (44.36 and 21.87%, respectively).
Table 5 shows the statistical information on fertility indicators in each grade in 2000 and 2015. It can be seen from tobacco-planting suitability, in 2000 and 2015, 26.81 and 26.73% of the samples were suitable in pH, 65.42 and 62.37% of the samples were higher in pH (including high and very higher grades, the same as below), and 7.77 and 10.90% of the samples were lower in pH (including low and very low grades, the same below). Most soil samples are high in OM, TN, AN, AK, Ca2+, S, B, Fe, Cu and Zn, among which, 86.06 and 90.33% of the samples were higher in OM, 79.36 and 83.13% of the samples were higher in TN, 75.60 and 64.55% of the samples were higher in AN, 82.44 and 27.30% of the samples were lower in AK, 67.52 and 85.12% of the samples were higher in Ca2+, 84.05 and 55.55% of the samples were higher in S, 84.05 and 55.55% of the samples were higher in B, 99.20 and 100% of the samples were higher in Fe, 99.06 and 99.72% of the samples were higher in Cu, and 70.64 and 77.73% of the samples were higher in Zn. Table 5 also shows that obvious proportions of soil samples were lower in TP, AP, Mg2+, Mo and Cl− in 2000 and 2015, among which, 90.75 and 79.81% of the samples were lower in TK, 60.05 and 59.24% of the samples were lower in TP, 38.61 and 60.00% of the samples were higher in AP, 40.13 and 32.04% of the samples were lower in Mg2+, 49.20 and 66.54% of the samples were lower in Mo, and 21.18 and 76.30% of the samples were lower in Cl−.
Grade statistic information of soil fertility indicators in 2000 and 2015 in Chenzhou
| Indicators | Year | Very low | Low | Suitable | High | Very high | Total | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. | % | No. | % | No. | % | No. | % | No. | % | No. | % | ||
| pH | 2000 | 18 | 2.41 | 40 | 5.36 | 200 | 26.81 | 61 | 8.18 | 427 | 57.24 | 746 | 100 |
| 2015 | 45 | 4.27 | 70 | 6.64 | 282 | 26.73 | 134 | 12.70 | 524 | 49.67 | 1,055 | 100 | |
| SOM | 2000 | 1 | 0.13 | 5 | 0.67 | 98 | 13.14 | 135 | 18.10 | 507 | 67.96 | 746 | 100 |
| 2015 | 1 | 0.09 | 0 | 0.00 | 101 | 9.57 | 224 | 21.23 | 729 | 69.10 | 1,055 | 100 | |
| TN | 2000 | 0 | 0.00 | 7 | 0.94 | 147 | 19.71 | 144 | 19.30 | 448 | 60.05 | 746 | 100 |
| 2015 | 0 | 0.00 | 0 | 0.00 | 178 | 16.87 | 278 | 26.35 | 599 | 56.78 | 1,055 | 100 | |
| AN | 2000 | 3 | 0.40 | 16 | 2.14 | 163 | 21.85 | 278 | 37.27 | 286 | 38.34 | 746 | 100 |
| 2015 | 1 | 0.09 | 17 | 1.61 | 356 | 33.74 | 438 | 41.52 | 243 | 23.03 | 1,055 | 100 | |
| TP | 2000 | 59 | 7.91 | 389 | 52.14 | 271 | 36.33 | 27 | 3.62 | / | 0.00 | 746 | 100 |
| 2015 | 73 | 6.92 | 552 | 52.32 | 415 | 39.34 | 15 | 1.42 | / | 0.00 | 1,055 | 100 | |
| AP | 2000 | 35 | 4.69 | 57 | 7.64 | 366 | 49.06 | 169 | 22.65 | 119 | 15.95 | 746 | 100 |
| 2015 | 30 | 2.84 | 73 | 6.92 | 319 | 30.24 | 231 | 21.90 | 402 | 38.10 | 1,055 | 100 | |
| TK | 2000 | 290 | 38.87 | 387 | 51.88 | 63 | 8.45 | 6 | 0.80 | 0 | 0.00 | 746 | 100 |
| 2015 | 206 | 19.53 | 636 | 60.28 | 167 | 15.83 | 34 | 3.22 | 12 | 1.14 | 1,055 | 100 | |
| AK | 2000 | 131 | 17.56 | 484 | 64.88 | 100 | 13.40 | 22 | 2.95 | 9 | 1.21 | 746 | 100 |
| 2015 | 54 | 5.12 | 234 | 22.18 | 337 | 31.94 | 372 | 35.26 | 58 | 5.50 | 1,055 | 100 | |
| Ca2+ | 2000 | 2 | 0.64 | 29 | 9.24 | 71 | 22.61 | 160 | 50.96 | 52 | 16.56 | 314 | 100 |
| 2015 | 2 | 0.19 | 47 | 4.45 | 108 | 10.24 | 234 | 22.18 | 664 | 62.94 | 1,055 | 100 | |
| Mg2+ | 2000 | 30 | 9.55 | 96 | 30.57 | 72 | 22.93 | 110 | 35.03 | 6 | 1.91 | 314 | 100 |
| 2015 | 72 | 6.82 | 266 | 25.21 | 248 | 23.51 | 375 | 35.55 | 94 | 8.91 | 1,055 | 100 | |
| S | 2000 | 5 | 0.67 | 23 | 3.08 | 91 | 12.20 | 257 | 34.45 | 370 | 49.60 | 746 | 100 |
| 2015 | 10 | 0.95 | 81 | 7.68 | 378 | 35.83 | 365 | 34.60 | 221 | 20.95 | 1,055 | 100 | |
| B | 2000 | 325 | 43.57 | 350 | 46.92 | 68 | 9.12 | 3 | 0.40 | 0 | 0.00 | 746 | 100 |
| 2015 | 0 | 0.00 | 39 | 3.70 | 656 | 62.18 | 329 | 31.18 | 31 | 2.94 | 1,055 | 100 | |
| Fe | 2000 | 0 | 0.00 | 1 | 0.13 | 5 | 0.67 | 368 | 49.33 | 372 | 49.87 | 746 | 100 |
| 2015 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 | 145 | 13.74 | 910 | 86.26 | 1,055 | 100 | |
| Mn | 2000 | 36 | 4.83 | 148 | 19.84 | 282 | 37.80 | 170 | 22.79 | 110 | 14.75 | 746 | 100 |
| 2015 | 49 | 4.64 | 88 | 8.34 | 278 | 26.35 | 362 | 34.31 | 278 | 26.35 | 1,055 | 100 | |
| Cu | 2000 | 0 | 0.00 | 1 | 0.13 | 6 | 0.80 | 156 | 20.91 | 583 | 78.15 | 746 | 100 |
| 2015 | 0 | 0.00 | 1 | 0.09 | 2 | 0.19 | 223 | 21.14 | 829 | 78.58 | 1,055 | 100 | |
| Zn | 2000 | 0 | 0.00 | 24 | 3.22 | 195 | 26.14 | 389 | 52.14 | 138 | 18.50 | 746 | 100 |
| 2015 | 2 | 0.19 | 28 | 2.65 | 205 | 19.43 | 511 | 48.44 | 309 | 29.29 | 1,055 | 100 | |
| Mo | 2000 | 223 | 29.89 | 144 | 19.30 | 114 | 15.28 | 126 | 16.89 | 139 | 18.63 | 746 | 100 |
| 2015 | 507 | 48.06 | 195 | 18.48 | 118 | 11.18 | 102 | 9.67 | 133 | 12.61 | 1,055 | 100 | |
| Cl− | 2000 | 64 | 8.58 | 94 | 12.60 | 512 | 68.63 | 50 | 6.70 | 26 | 3.49 | 746 | 100 |
| 2015 | 683 | 64.74 | 122 | 11.56 | 218 | 20.66 | 13 | 1.23 | 19 | 1.80 | 1,055 | 100 | |
3.2 Statistics and comparison of soil IFIs
Tables 6 and 7 present the general and grade statistical results of soil IFIs of tobacco-planting fields, respectively. Tables 6 and 7 show that there was no sample with IFI < 0.2 or ≥0.8 both in 2000 and in 2015, IFI were within 0.230–0.740 with a mean of 0.492 in 2000 and 0.320–0.760 with a mean of 0.556 in 2015, and both covered the lower (<0.2), middle (0.2–0.4) and higher grades (0.4–0.6). However, it also can be seen that the average IFI significantly increased by 13.01% (Sig. = 0.000) from 2000 to 2015. IFI in both 2000 and 2015 belonged to the moderate variation, negative skew distribution in 2000 but near normal distribution in 2015, and flat peak distribution in 2000 and 2015 [31,32]. It is shown in Table 7 that the samples with IFI within 0.4–0.6 were most both in 2000 (77.35%) and 2015 (70.52%), and the sample proportions with IFI within 0.2–0.4 and 0.4–0.6 were decreased from 12.87% in 2000 to 1.61% in 2015 and from 77.35% in 2000 to 70.52% in 2015, respectively, while the sample proportion with IFI within 0.6–0.8 increased from 9.79% in 2000 to 27.87% in 2015.
Statistic information of soil IFIs in 2000 and 2015 in Chenzhou
| Region | Year | Sample No. | Min | Max | Mean ± S.D. | C.V. (%) | Skewness | Kurtosis |
|---|---|---|---|---|---|---|---|---|
| Guiyang | 2000 | 447 | 0.254 | 0.715 | 0.486 ± 0.077A | 15.821 | 0.230 | −0.227 |
| 2015 | 560 | 0.319 | 0.756 | 0.559 ± 0.076B | 13.65 | −0.014 | −0.087 | |
| Jiahe | 2000 | 100 | 0.237 | 0.736 | 0.492 ± 0.086A | 17.512 | 0.123 | 0.353 |
| 2015 | 110 | 0.408 | 0.737 | 0.554 ± 0.073B | 13.10 | 0.174 | −0.504 | |
| Yongxing | 2000 | 73 | 0.229 | 0.735 | 0.498 ± 0.094A | 18.901 | −0.121 | 0.368 |
| 2015 | 115 | 0.375 | 0.691 | 0.547 ± 0.063B | 11.57 | −0.031 | −0.345 | |
| Anren | 2000 | 35 | 0.369 | 0.702 | 0.520 ± 0.084A | 16.149 | 0.320 | −0.338 |
| 2015 | 100 | 0.438 | 0.711 | 0.563 ± 0.061B | 10.76 | 0.164 | −0.334 | |
| Yizhang | 2000 | 29 | 0.371 | 0.613 | 0.486 ± 0.069A | 14.082 | 0.236 | −0.974 |
| 2015 | 96 | 0.351 | 0.725 | 0.548 ± 0.081B | 14.70 | −0.007 | −0.379 | |
| Suxian | 2000 | 20 | 0.396 | 0.623 | 0.508 ± 0.071a | 13.959 | −0.018 | −0.979 |
| 2015 | 45 | 0.347 | 0.666 | 0.546 ± 0.077b | 14.10 | −0.668 | 0.141 | |
| Beihu | 2000 | 12 | 0.419 | 0.608 | 0.526 ± 0.064a | 12.220 | −0.533 | −1.010 |
| 2015 | 17 | 0.419 | 0.674 | 0.587 ± 0.066a | 11.30 | −0.740 | 1.100 | |
| Linwu | 2000 | 30 | 0.350 | 0.637 | 0.511 ± 0.087a | 17.076 | −0.186 | −0.957 |
| 2015 | 12 | 0.349 | 0.654 | 0.548 ± 0.085a | 15.55 | −0.942 | 1.680 | |
| Total | 2000 | 746 | 0.230 | 0.740 | 0.492 ± 0.080A | 16.26 | 0.150 | −0.087 |
| 2015 | 1,055 | 0.320 | 0.760 | 0.556 ± 0.074B | 13.25 | −0.040 | −0.101 |
Lowercase and majuscule indicate significant differences at the 0.05 and 0.01 levels, respectively.
Grade statistic information of soil IFIs in 2000 and 2015 in Chenzhou
| Region | Year | IFI | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Highest (≥0.8) | Higher (0.6–0.8) | Middle (0.4–0.6) | Lower (0.2–0.4) | Lowest ( < 0.2) | |||||||
| No. | % | No. | % | No. | % | No. | % | No. | % | ||
| Guiyang | 2000 | 0 | 0 | 36 | 8.05 | 348 | 77.85 | 63 | 12.00 | 0 | 0 |
| 2015 | 0 | 0 | 158 | 28.21 | 393 | 70.18 | 9 | 1.61 | 0 | 0 | |
| Jiahe | 2000 | 0 | 0 | 9 | 6.00 | 79 | 79.00 | 12 | 12.00 | 0 | 0 |
| 2015 | 0 | 0 | 25 | 22.73 | 84 | 76.36 | 1 | 0.91 | 0 | 0 | |
| Yongxing | 2000 | 0 | 0 | 10 | 13.70 | 54 | 73.97 | 9 | 12.33 | 0 | 0 |
| 2015 | 0 | 0 | 33 | 28.00 | 82 | 71.30 | 0 | 0 | 0 | 0 | |
| Anren | 2000 | 0 | 0 | 5 | 14.29 | 27 | 77.14 | 3 | 8.57 | 0 | 0 |
| 2015 | 0 | 0 | 28 | 28.00 | 72 | 72.00 | 0 | 0 | 0 | 0 | |
| Yizhang | 2000 | 0 | 0 | 2 | 6.90 | 24 | 82.76 | 3 | 10.34 | 0 | 0 |
| 2015 | 0 | 0 | 29 | 30.21 | 64 | 66.67 | 3 | 3.13 | 0 | 0 | |
| Suxian | 2000 | 0 | 0 | 2 | 10.00 | 17 | 85.00 | 1 | 5.00 | 0 | 0 |
| 2015 | 0 | 0 | 11 | 24.44 | 31 | 68.89 | 3 | 6.67 | 0 | 0 | |
| Beihu | 2000 | 0 | 0 | 2 | 16.67 | 10 | 83.33 | 0 | 0 | 0 | 0 |
| 2015 | 0 | 0 | 7 | 41.18 | 10 | 58.82 | 0 | 0 | 0 | 0 | |
| Linwu | 2000 | 0 | 0 | 7 | 23.33 | 18 | 60.00 | 5 | 16.67 | 0 | 0 |
| 2015 | 0 | 0 | 3 | 25.00 | 8 | 66.67 | 1 | 8.33 | 0 | 0 | |
| Total | 2000 | 0 | 0 | 73 | 9.79 | 577 | 77.35 | 96 | 12.87 | 0 | 0 |
| 2015 | 0 | 0 | 294 | 27.87 | 744 | 70.52 | 17 | 1.61 | 0 | 0 | |
From 2000 to 2015, IFI was significantly increased by 13.00% in total (Sig. 000), 14.94% in Guiyang (Sig. = 0.000), 12.70% in Jiahe (Sig. = 0.000), 9.74% in Yongxing (Sigs. = 0.000), 8.24% in Anren (Sig. = 0.001), 12.72% in Yizhang (Sig. = 0.001) and 7.47% in Suxian (Sig. = 0.024), while IFI was increased insignificantly by 11.56 and 7.13% in Beihu (Sig. = 0.147) and in Linwu (Sig. = 0.248). Difference significance test results also showed that in 2000 significant difference in IFI was only founded between Guiyang with Linwu (Sig. = 0.009) and Anren (Sig. = 0.014), and no significant difference among the other regions (Sig. = 0.052–0.977 with a mean of 0.330), while in 2015 significant difference in IFI was only founded between Anren and Suxian (Sig. = 0.047), and no significant difference among the other regions (Sig. = 0.060–0.978 with a mean of 0.442).
Table 7 shows that in 2000 and 2015, the numbers of samples were the most in the middle grade of IFI among the total samples, which were 77.35 and 70.52% in total, 77.85 and 70.18% in Guiyang, 79.00 and 76.36% in Jiahe, 73.97 and 71.30% in Yongxing, 77.14 and 72.00% in Anren, 82.76 and 66.67% in Yizhang, 85.00 and 68.89% in Suxian, 83.33 and 58.82% in Beihu, and 60.00 and 66.67% in Linwu. Table 7 also shows that the proportion of samples in the higher grade of IFI was increased from 9.79% in 2000 to 27.87% in 2015 in total, while that of samples in the lower grade of IFI were decreased from 12.87% in 2000 to 1.61% in 2015 in total.
4 Discussion
Soil fertility assessment is one of the most basic works in soil science research, but it is very important for crop planting; therefore, the latest literature studies could be found even now [33,34,35,36,37]. Meanwhile, soil fertility evaluation of tobacco planting also has been reported more so far; however, the fertility indicators mainly involve pH, OM, TN, AN, TP, AP, TK, AK, Ca2+, Mg2+, trace elements of B, Fe, Mg, Cu and Zn, and Cl−; in our study, besides the above indicators, S and Mo were also added; thus, it should be said that the fertility indicators are more complete in our study, which would enable the obtained results are closer to the reality and more feasible in guiding the scientific fertilization and soil improvement. It should be pointed out that CEC is also one of the most important indicators of soil fertility; however, as in many studies of soil fertility assessment conducted in China, the determined indicators of soil fertility usually include soil pH and the contents of OM and main nutrients [1,2,3,4,5], which can not only understand the real state of in each index (whether suitable or not for high-quality tobacco planting) in order to guide the reasonable fertilization and soil improvement, but also can evaluate soil comprehensive fertility based on these indicators. The reason why CEC is rarely used is that CEC is a comprehensive indicator of soil fertility, it can only indicate the general level of soil fertility, but cannot provide the real information on soil pH and the contents of OM and nutrient contents, thus cannot guide the reasonable fertilizer application and soil improvement; therefore, CEC was also not used in our study. Meanwhile, soil pH and OM content are the factors that can influence CEC, so CEC can be omitted when pH and OM are used for soil fertility assessment. We add some content in the second revised manuscript. Meanwhile, the Ca/K and Ca/Mg ratios should be considered in the assessment of soil fertility for tobacco-planting, which is important to instruct the scientific application of potassium by reflecting the nutrient antagonism in soils, but currently, there are no threshold values or grade classifications of Ca/K and Ca/Mg for tobacco, so these two ratios were also not used in this study.
As shown in Table 5, 65.42 and 62.37% of the samples were higher in pH (≥7.0) in 2000 and 2015, respectively. The high value of soil pH of tobacco-planting fields in Chenzhou could be attributed to the application of superphosphate fertilizer and the habit of local farmers using fired soil to improve soil quality [38,39], and it may also be related to that tobacco-planting fields in Chenzhou are mostly located in the limestone hill and mountainous area [10], which also resulted in the increases of Ca2+ and Mg2+ from 2000 to 2015, increased significantly by 157.31 and 20.44%, respectively (Table 4).
OM was increased from 38.8 g/kg in the 1980s to 45.87 g/kg in 2000 and to 48.00 g/kg in 2015, the increase was decided by tobacco-rice rotation, straw returning to the field and organic fertilizer application [11,40,41]. AN increased from 147.97 mg/kg in the 1980s to 224.76 mg/kg in 2000 and then decreased to 202.98 mg/kg in 2015, the decrease in AN from 2000 to 2015 is because the higher content of AN in 2000 is unsuitable (suitable grade is 100–180 mg/kg) for the high-quality tobacco [25], and thus, the applied amount of nitrogen fertilizer was reduced gradually [42]. AP increased from 8.90 mg/kg in the 1980s to 28.20 mg/kg in 2000 and to 36.48 mg/kg in 2015; the remarkable continuous increase could be attributed to the long-term excessive application of phosphatic fertilizer by farmers in China due to the cheap price and yield-increase effect [43,44]. AK increased from 76.6 mg/kg in the 1980s to 120.75 mg/kg in 2000 and to 205.71 mg/kg in 2015, the continuous significant increase was contributed by the large amount application of potassium to guarantee the high-quality tobacco leaves usually with high K content [1,2,3,4,5]. S deceased from 51.92 mg/kg in 2000 to 39.42 mg/kg in 2015, which could be attributed to the reduced use of potassium sulfate for tobacco-planting because it caused soil acidification, and usually high content of S would worsen the quality of tobacco leaves [45,46]. Cl− decreased from 18.49 mg/kg in 2000 to 6.30 mg/kg in 2015, which could be attributed to the worry that high Cl− content could severely deteriorate the quality of tobacco leaves, so chlorine fertilizer is seldom used for tobacco-planting in many regions [47]. Mo decreased from 0.25 mg/kg in the 1980s to 0.21 mg/kg in 2000 and to 0.16 mg/kg in 2015, which may be related to little concern about Mo and little literature on Mo fertilizer application for tobacco-planting in Hunan [48]. Cu increased from 3.74 mg/kg in the 1980s to 4.36 mg/kg in 2000 and to 4.70 mg/kg in 2015, the increase, on the one hand, may be related to the application of livestock and poultry manure which usually containing Cu [49,50], and on the other hand, may be related to the higher Cu content in paddy soil itself [51,52], as for the changes of B, Zn, Mn and Fe, which decreased from the 1980s to 2010 and then increased from 2000 to 2015, which could be attributed to the gradual application of related trace fertilizers in the farmlands [53].
Li et al. [23] compared soil fertility indicators tobacco-growing areas in Kunming in southwest China in 2010 and 2020 and found that from 2010 to 2020, soil pH decreased by 0.15 units. Soil SOM, N, P and K increased by 1.87 g/kg, 7.21 mg/kg, 5.17 mg/kg and 53.05 mg/kg, respectively; the overall soil fertility increased, and these findings are generally similar to the results in our study.
The change of climate may influence the changes in soil chemical properties, so we analyzed the correlation between the mean annual temperature (T) and precipitation (P) with years from 2000 and 2015, and the results showed that the ranges of the two parameters were 17.9–19.1°C and 1069–1854 mm with the means of 18.6°C and 1450 mm, respectively; but there was no significant correlation between T and P with year. The Pearson coefficients were 0.499 (p = 0.082) and 0.224 (p = 0.462), respectively, which means it is hard to clarify the influence of climate change on the change of soil fertility instructors.
Soil fertility affects or determines the growth, yield and quality of tobacco; it also determines the economic benefits of local tobacco-planting farmers, so more and great concerns have been paid continuously to soil improvement in the tobacco-planting regions with higher input and sufficient guarantee, almost all the tobacco-planting regions in China have formulated and implemented the technical regulation of flue-cured tobacco planting, which enable the same measures adopted for tobacco-planting in ploughing, ridging, fertilization, irrigation, film mulching, etc. It may homogenize the soil fertility of tobacco-planting fields in a large region, so no significant difference in IFI was found in this study between most tobacco-planting regions in Chenzhou, in which significant difference in IFI was only founded between Guiyang with Linwu (Sig. = 0.009) and Anren (Sig. = 0.014) in 2000 and between Anren and Suxian (Sig. = 0.047) in 2015. Our study also showed the increasing tendency of soil IFI of tobacco-planting fields in Chenzhou, it was not only proved by the increases in the contents of OM, AN, AP and AK from 1980 to 2000 (Table 1), meanwhile, but also proved by the proportion of fields with the lower grade of IFI was decreased from 12.87% in 2000 to 1.61% in 2015, the proportion of fields with the higher grade of IFI was increased from 9.79% in 2000 to 27.87% in 2015, and IFI meanly increased from 0.492 in 2000 to 0.556 in 2015, increased by 13.00%. However, it should be pointed out that the soil fertility of tobacco-planting fields in Chenzhou is still in the middle level of IFI (0.4–0.6), the proportion of tobacco-planting fields with the middle grade of IFI was the highest (77.35% in 2000 and 70.52% in 2015), and there was no tobacco-plating field with the highest grade of IFI (≥0.8); therefore, the soil fertility of tobacco-planting fields in Chenzhou still needs to be promoted.
The annual fertilization for tobacco fields in Chenzhou is generally as follows from 2000 to 2015: during tobacco growing season, about 178.5 (N), 139.65 (P2O5) and 420 (K2O) kg/ha are applied in the forms of compound fertilizers, and during rice growing season, about 0–375 kg/ha of the compound fertilizer (N:P2O5:K2O = 15:15:15) and 0–75 kg/ha of urea (N = 46.2%) are applied according to the growing status of rice. Meanwhile, this fertilization pattern is almost the same and seldom changed from 2000 to 2015. From the improvement of tobacco planting soil, it can be seen that in 2015 there were 62.37 and 10.90% of the samples were higher and lower in pH. These tobacco-planting fields should be paid attention to the modification of soil alkalinity or acidity; 90.33, 83.13 and 64.55% of the samples were higher in OM, TN and AN, respectively, and these fields need to reduce the use of organic and nitrogen fertilizers. In Ca2+ and Mg2+, 85.12 and 44.45% of the samples were higher, respectively; these fields should be controlled by the application of alkaline substances or calcium and magnesium fertilizers. 27.61, 32.04, 12.99, 66.54 and 76.30% of the samples were lower in AK, Mg2+, Mn, Mo and Cl−, respectively; these fields should be applied with the corresponding fertilizers. Usually, tobacco is a chlorine-free crop, but chlorine is also one of the essential nutrients for tobacco growth [5], and some studies conducted in south China have shown that proper application of chlorine fertilizer to Cl-deficient soils could increase the elasticity, oiliness and yield of tobacco leaves while not reducing the quality of tobacco leaves [47,54]. Nevertheless, for the fields with higher contents of other various nutrients, such as S, Fe, Cu and Mn, there is no need to apply the corresponding fertilizers.
It should be pointed out that there is a certain relationship between soil fertility or IFI with the growth, yield and quality of tobacco [7,55,56,57,58]; it is not evaluated in this study but would be conducted in our further research.
5 Conclusion
This study compared the values of topsoil (0–20 cm) fertility indicators of tobacco planting area in Chenzhou in 1980s, 2000 and 2015 and found that soil pH value was decreased, TN, OM, AP, AK, Ca, Mg and Cu contents were increased, TP, S and Cl contents were decreased, and TK, B, Fe, Mn and Zn were decreased first and then an increased. In 2015, most of the samples (44.45–100%) were higher in pH, OM, TN, AN, AK, Ca2+, Mg2+, S, Fe, Mn, Cu and Zn, most of the samples (62.18%) were suitable in B, while most of the samples (59.24–79.81%) were lower in TK, Mo and Cl−. Most of the samples were in the middle grade of IFI (77.35% in 2000 and 70.52% in 2015), and the mean IFI was increased by 13.00% from 0.492 in 2000 to 0.556 in 2015, but both still belonged to the middle grade of IFI. Thus, soil fertility still needs to be promoted, and more attentions should be paid to modify of soil acidity and alkalinity, reduce the application of organic, nitrogen, calcium fertilizers, and increase the application of fertilizers of potassium, magnesium, molybdate and chloride according to the real situation of tobacco-planting fields.
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Funding information: Authors state no funding involved.
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Conflict of interest: Authors state no conflict of interest.
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Data availability statement: Due to confidentiality agreements, supporting data can only be made available to bona fide researchers subject to a non-disclosure agreement. Details of the data and how to request access are available from Mrs. Yansong Xiao (Email: 35149517@qq.com, Mobile No: +86-18975717573) at Chenzhou Tobacco Company of Hunan Province.
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- Concanavalin A-induced autoimmune hepatitis model in mice: Mechanisms and future outlook
- Regulation of miR-30b in cancer development, apoptosis, and drug resistance
- Informatic analysis of the pulmonary microecology in non-cystic fibrosis bronchiectasis at three different stages
- Swimming attenuates tumor growth in CT-26 tumor-bearing mice and suppresses angiogenesis by mediating the HIF-1α/VEGFA pathway
- Characterization of intestinal microbiota and serum metabolites in patients with mild hepatic encephalopathy
- Functional conservation and divergence in plant-specific GRF gene family revealed by sequences and expression analysis
- Application of the FLP/LoxP-FRT recombination system to switch the eGFP expression in a model prokaryote
- Biomedical evaluation of antioxidant properties of lamb meat enriched with iodine and selenium
- Intravenous infusion of the exosomes derived from human umbilical cord mesenchymal stem cells enhance neurological recovery after traumatic brain injury via suppressing the NF-κB pathway
- Effect of dietary pattern on pregnant women with gestational diabetes mellitus and its clinical significance
- Potential regulatory mechanism of TNF-α/TNFR1/ANXA1 in glioma cells and its role in glioma cell proliferation
- Effect of the genetic mutant G71R in uridine diphosphate-glucuronosyltransferase 1A1 on the conjugation of bilirubin
- Quercetin inhibits cytotoxicity of PC12 cells induced by amyloid-beta 25–35 via stimulating estrogen receptor α, activating ERK1/2, and inhibiting apoptosis
- Nutrition intervention in the management of novel coronavirus pneumonia patients
- circ-CFH promotes the development of HCC by regulating cell proliferation, apoptosis, migration, invasion, and glycolysis through the miR-377-3p/RNF38 axis
- Bmi-1 directly upregulates glucose transporter 1 in human gastric adenocarcinoma
- Lacunar infarction aggravates the cognitive deficit in the elderly with white matter lesion
- Hydroxysafflor yellow A improved retinopathy via Nrf2/HO-1 pathway in rats
- Comparison of axon extension: PTFE versus PLA formed by a 3D printer
- Elevated IL-35 level and iTr35 subset increase the bacterial burden and lung lesions in Mycobacterium tuberculosis-infected mice
- A case report of CAT gene and HNF1β gene variations in a patient with early-onset diabetes
- Study on the mechanism of inhibiting patulin production by fengycin
- SOX4 promotes high-glucose-induced inflammation and angiogenesis of retinal endothelial cells by activating NF-κB signaling pathway
- Relationship between blood clots and COVID-19 vaccines: A literature review
- Analysis of genetic characteristics of 436 children with dysplasia and detailed analysis of rare karyotype
- Bioinformatics network analyses of growth differentiation factor 11
- NR4A1 inhibits the epithelial–mesenchymal transition of hepatic stellate cells: Involvement of TGF-β–Smad2/3/4–ZEB signaling
- Expression of Zeb1 in the differentiation of mouse embryonic stem cell
- Study on the genetic damage caused by cadmium sulfide quantum dots in human lymphocytes
- Association between single-nucleotide polymorphisms of NKX2.5 and congenital heart disease in Chinese population: A meta-analysis
- Assessment of the anesthetic effect of modified pentothal sodium solution on Sprague-Dawley rats
- Genetic susceptibility to high myopia in Han Chinese population
- Potential biomarkers and molecular mechanisms in preeclampsia progression
- Silencing circular RNA-friend leukemia virus integration 1 restrained malignancy of CC cells and oxaliplatin resistance by disturbing dyskeratosis congenita 1
- Endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime for advanced pulmonary large-cell neuroendocrine carcinoma as a first-line treatment: A case report
- The significance of PAK4 in signaling and clinicopathology: A review
- Sorafenib inhibits ovarian cancer cell proliferation and mobility and induces radiosensitivity by targeting the tumor cell epithelial–mesenchymal transition
- Characterization of rabbit polyclonal antibody against camel recombinant nanobodies
- Active legumain promotes invasion and migration of neuroblastoma by regulating epithelial-mesenchymal transition
- Effect of cell receptors in the pathogenesis of osteoarthritis: Current insights
- MT-12 inhibits the proliferation of bladder cells in vitro and in vivo by enhancing autophagy through mitochondrial dysfunction
- Study of hsa_circRNA_000121 and hsa_circRNA_004183 in papillary thyroid microcarcinoma
- BuyangHuanwu Decoction attenuates cerebral vasospasm caused by subarachnoid hemorrhage in rats via PI3K/AKT/eNOS axis
- Effects of the interaction of Notch and TLR4 pathways on inflammation and heart function in septic heart
- Monosodium iodoacetate-induced subchondral bone microstructure and inflammatory changes in an animal model of osteoarthritis
- A rare presentation of type II Abernethy malformation and nephrotic syndrome: Case report and review
- Rapid death due to pulmonary epithelioid haemangioendothelioma in several weeks: A case report
- Hepatoprotective role of peroxisome proliferator-activated receptor-α in non-cancerous hepatic tissues following transcatheter arterial embolization
- Correlation between peripheral blood lymphocyte subpopulations and primary systemic lupus erythematosus
- A novel SLC8A1-ALK fusion in lung adenocarcinoma confers sensitivity to alectinib: A case report
- β-Hydroxybutyrate upregulates FGF21 expression through inhibition of histone deacetylases in hepatocytes
- Identification of metabolic genes for the prediction of prognosis and tumor microenvironment infiltration in early-stage non-small cell lung cancer
- BTBD10 inhibits glioma tumorigenesis by downregulating cyclin D1 and p-Akt
- Mucormycosis co-infection in COVID-19 patients: An update
- Metagenomic next-generation sequencing in diagnosing Pneumocystis jirovecii pneumonia: A case report
- Long non-coding RNA HOXB-AS1 is a prognostic marker and promotes hepatocellular carcinoma cells’ proliferation and invasion
- Preparation and evaluation of LA-PEG-SPION, a targeted MRI contrast agent for liver cancer
- Proteomic analysis of the liver regulating lipid metabolism in Chaohu ducks using two-dimensional electrophoresis
- Nasopharyngeal tuberculosis: A case report
- Characterization and evaluation of anti-Salmonella enteritidis activity of indigenous probiotic lactobacilli in mice
- Aberrant pulmonary immune response of obese mice to periodontal infection
- Bacteriospermia – A formidable player in male subfertility
- In silico and in vivo analysis of TIPE1 expression in diffuse large B cell lymphoma
- Effects of KCa channels on biological behavior of trophoblasts
- Interleukin-17A influences the vulnerability rather than the size of established atherosclerotic plaques in apolipoprotein E-deficient mice
- Multiple organ failure and death caused by Staphylococcus aureus hip infection: A case report
- Prognostic signature related to the immune environment of oral squamous cell carcinoma
- Primary and metastatic squamous cell carcinoma of the thyroid gland: Two case reports
- Neuroprotective effects of crocin and crocin-loaded niosomes against the paraquat-induced oxidative brain damage in rats
- Role of MMP-2 and CD147 in kidney fibrosis
- Geometric basis of action potential of skeletal muscle cells and neurons
- Babesia microti-induced fulminant sepsis in an immunocompromised host: A case report and the case-specific literature review
- Role of cerebellar cortex in associative learning and memory in guinea pigs
- Application of metagenomic next-generation sequencing technique for diagnosing a specific case of necrotizing meningoencephalitis caused by human herpesvirus 2
- Case report: Quadruple primary malignant neoplasms including esophageal, ureteral, and lung in an elderly male
- Long non-coding RNA NEAT1 promotes angiogenesis in hepatoma carcinoma via the miR-125a-5p/VEGF pathway
- Osteogenic differentiation of periodontal membrane stem cells in inflammatory environments
- Knockdown of SHMT2 enhances the sensitivity of gastric cancer cells to radiotherapy through the Wnt/β-catenin pathway
- Continuous renal replacement therapy combined with double filtration plasmapheresis in the treatment of severe lupus complicated by serious bacterial infections in children: A case report
- Simultaneous triple primary malignancies, including bladder cancer, lymphoma, and lung cancer, in an elderly male: A case report
- Preclinical immunogenicity assessment of a cell-based inactivated whole-virion H5N1 influenza vaccine
- One case of iodine-125 therapy – A new minimally invasive treatment of intrahepatic cholangiocarcinoma
- S1P promotes corneal trigeminal neuron differentiation and corneal nerve repair via upregulating nerve growth factor expression in a mouse model
- Early cancer detection by a targeted methylation assay of circulating tumor DNA in plasma
- Calcifying nanoparticles initiate the calcification process of mesenchymal stem cells in vitro through the activation of the TGF-β1/Smad signaling pathway and promote the decay of echinococcosis
- Evaluation of prognostic markers in patients infected with SARS-CoV-2
- N6-Methyladenosine-related alternative splicing events play a role in bladder cancer
- Characterization of the structural, oxidative, and immunological features of testis tissue from Zucker diabetic fatty rats
- Effects of glucose and osmotic pressure on the proliferation and cell cycle of human chorionic trophoblast cells
- Investigation of genotype diversity of 7,804 norovirus sequences in humans and animals of China
- Characteristics and karyotype analysis of a patient with turner syndrome complicated with multiple-site tumors: A case report
- Aggravated renal fibrosis is positively associated with the activation of HMGB1-TLR2/4 signaling in STZ-induced diabetic mice
- Distribution characteristics of SARS-CoV-2 IgM/IgG in false-positive results detected by chemiluminescent immunoassay
- SRPX2 attenuated oxygen–glucose deprivation and reperfusion-induced injury in cardiomyocytes via alleviating endoplasmic reticulum stress-induced apoptosis through targeting PI3K/Akt/mTOR axis
- Aquaporin-8 overexpression is involved in vascular structure and function changes in placentas of gestational diabetes mellitus patients
- Relationship between CRP gene polymorphisms and ischemic stroke risk: A systematic review and meta-analysis
- Effects of growth hormone on lipid metabolism and sexual development in pubertal obese male rats
- Cloning and identification of the CTLA-4IgV gene and functional application of vaccine in Xinjiang sheep
- Antitumor activity of RUNX3: Upregulation of E-cadherin and downregulation of the epithelial–mesenchymal transition in clear-cell renal cell carcinoma
- PHF8 promotes osteogenic differentiation of BMSCs in old rat with osteoporosis by regulating Wnt/β-catenin pathway
- A review of the current state of the computer-aided diagnosis (CAD) systems for breast cancer diagnosis
- Bilateral dacryoadenitis in adult-onset Still’s disease: A case report
- A novel association between Bmi-1 protein expression and the SUVmax obtained by 18F-FDG PET/CT in patients with gastric adenocarcinoma
- The role of erythrocytes and erythroid progenitor cells in tumors
- Relationship between platelet activation markers and spontaneous abortion: A meta-analysis
- Abnormal methylation caused by folic acid deficiency in neural tube defects
- Silencing TLR4 using an ultrasound-targeted microbubble destruction-based shRNA system reduces ischemia-induced seizures in hyperglycemic rats
- Plant Sciences
- Seasonal succession of bacterial communities in cultured Caulerpa lentillifera detected by high-throughput sequencing
- Cloning and prokaryotic expression of WRKY48 from Caragana intermedia
- Novel Brassica hybrids with different resistance to Leptosphaeria maculans reveal unbalanced rDNA signal patterns
- Application of exogenous auxin and gibberellin regulates the bolting of lettuce (Lactuca sativa L.)
- Phytoremediation of pollutants from wastewater: A concise review
- Genome-wide identification and characterization of NBS-encoding genes in the sweet potato wild ancestor Ipomoea trifida (H.B.K.)
- Alleviative effects of magnetic Fe3O4 nanoparticles on the physiological toxicity of 3-nitrophenol to rice (Oryza sativa L.) seedlings
- Selection and functional identification of Dof genes expressed in response to nitrogen in Populus simonii × Populus nigra
- Study on pecan seed germination influenced by seed endocarp
- Identification of active compounds in Ophiopogonis Radix from different geographical origins by UPLC-Q/TOF-MS combined with GC-MS approaches
- The entire chloroplast genome sequence of Asparagus cochinchinensis and genetic comparison to Asparagus species
- Genome-wide identification of MAPK family genes and their response to abiotic stresses in tea plant (Camellia sinensis)
- Selection and validation of reference genes for RT-qPCR analysis of different organs at various development stages in Caragana intermedia
- Cloning and expression analysis of SERK1 gene in Diospyros lotus
- Integrated metabolomic and transcriptomic profiling revealed coping mechanisms of the edible and medicinal homologous plant Plantago asiatica L. cadmium resistance
- A missense variant in NCF1 is associated with susceptibility to unexplained recurrent spontaneous abortion
- Assessment of drought tolerance indices in faba bean genotypes under different irrigation regimes
- The entire chloroplast genome sequence of Asparagus setaceus (Kunth) Jessop: Genome structure, gene composition, and phylogenetic analysis in Asparagaceae
- Food Science
- Dietary food additive monosodium glutamate with or without high-lipid diet induces spleen anomaly: A mechanistic approach on rat model
- Binge eating disorder during COVID-19
- Potential of honey against the onset of autoimmune diabetes and its associated nephropathy, pancreatitis, and retinopathy in type 1 diabetic animal model
- FTO gene expression in diet-induced obesity is downregulated by Solanum fruit supplementation
- Physical activity enhances fecal lactobacilli in rats chronically drinking sweetened cola beverage
- Supercritical CO2 extraction, chemical composition, and antioxidant effects of Coreopsis tinctoria Nutt. oleoresin
- Functional constituents of plant-based foods boost immunity against acute and chronic disorders
- Effect of selenium and methods of protein extraction on the proteomic profile of Saccharomyces yeast
- Microbial diversity of milk ghee in southern Gansu and its effect on the formation of ghee flavor compounds
- Ecology and Environmental Sciences
- Effects of heavy metals on bacterial community surrounding Bijiashan mining area located in northwest China
- Microorganism community composition analysis coupling with 15N tracer experiments reveals the nitrification rate and N2O emissions in low pH soils in Southern China
- Genetic diversity and population structure of Cinnamomum balansae Lecomte inferred by microsatellites
- Preliminary screening of microplastic contamination in different marine fish species of Taif market, Saudi Arabia
- Plant volatile organic compounds attractive to Lygus pratensis
- Effects of organic materials on soil bacterial community structure in long-term continuous cropping of tomato in greenhouse
- Effects of soil treated fungicide fluopimomide on tomato (Solanum lycopersicum L.) disease control and plant growth
- Prevalence of Yersinia pestis among rodents captured in a semi-arid tropical ecosystem of south-western Zimbabwe
- Effects of irrigation and nitrogen fertilization on mitigating salt-induced Na+ toxicity and sustaining sea rice growth
- Bioengineering and Biotechnology
- Poly-l-lysine-caused cell adhesion induces pyroptosis in THP-1 monocytes
- Development of alkaline phosphatase-scFv and its use for one-step enzyme-linked immunosorbent assay for His-tagged protein detection
- Development and validation of a predictive model for immune-related genes in patients with tongue squamous cell carcinoma
- Agriculture
- Effects of chemical-based fertilizer replacement with biochar-based fertilizer on albic soil nutrient content and maize yield
- Genome-wide identification and expression analysis of CPP-like gene family in Triticum aestivum L. under different hormone and stress conditions
- Agronomic and economic performance of mung bean (Vigna radiata L.) varieties in response to rates of blended NPS fertilizer in Kindo Koysha district, Southern Ethiopia
- Influence of furrow irrigation regime on the yield and water consumption indicators of winter wheat based on a multi-level fuzzy comprehensive evaluation
- Discovery of exercise-related genes and pathway analysis based on comparative genomes of Mongolian originated Abaga and Wushen horse
- Lessons from integrated seasonal forecast-crop modelling in Africa: A systematic review
- Evolution trend of soil fertility in tobacco-planting area of Chenzhou, Hunan Province, China
- Animal Sciences
- Morphological and molecular characterization of Tatera indica Hardwicke 1807 (Rodentia: Muridae) from Pothwar, Pakistan
- Research on meat quality of Qianhua Mutton Merino sheep and Small-tail Han sheep
- SI: A Scientific Memoir
- Suggestions on leading an academic research laboratory group
- My scientific genealogy and the Toronto ACDC Laboratory, 1988–2022
- Erratum
- Erratum to “Changes of immune cells in patients with hepatocellular carcinoma treated by radiofrequency ablation and hepatectomy, a pilot study”
- Erratum to “A two-microRNA signature predicts the progression of male thyroid cancer”
- Retraction
- Retraction of “Lidocaine has antitumor effect on hepatocellular carcinoma via the circ_DYNC1H1/miR-520a-3p/USP14 axis”
Articles in the same Issue
- Biomedical Sciences
- Effects of direct oral anticoagulants dabigatran and rivaroxaban on the blood coagulation function in rabbits
- The mother of all battles: Viruses vs humans. Can humans avoid extinction in 50–100 years?
- Knockdown of G1P3 inhibits cell proliferation and enhances the cytotoxicity of dexamethasone in acute lymphoblastic leukemia
- LINC00665 regulates hepatocellular carcinoma by modulating mRNA via the m6A enzyme
- Association study of CLDN14 variations in patients with kidney stones
- Concanavalin A-induced autoimmune hepatitis model in mice: Mechanisms and future outlook
- Regulation of miR-30b in cancer development, apoptosis, and drug resistance
- Informatic analysis of the pulmonary microecology in non-cystic fibrosis bronchiectasis at three different stages
- Swimming attenuates tumor growth in CT-26 tumor-bearing mice and suppresses angiogenesis by mediating the HIF-1α/VEGFA pathway
- Characterization of intestinal microbiota and serum metabolites in patients with mild hepatic encephalopathy
- Functional conservation and divergence in plant-specific GRF gene family revealed by sequences and expression analysis
- Application of the FLP/LoxP-FRT recombination system to switch the eGFP expression in a model prokaryote
- Biomedical evaluation of antioxidant properties of lamb meat enriched with iodine and selenium
- Intravenous infusion of the exosomes derived from human umbilical cord mesenchymal stem cells enhance neurological recovery after traumatic brain injury via suppressing the NF-κB pathway
- Effect of dietary pattern on pregnant women with gestational diabetes mellitus and its clinical significance
- Potential regulatory mechanism of TNF-α/TNFR1/ANXA1 in glioma cells and its role in glioma cell proliferation
- Effect of the genetic mutant G71R in uridine diphosphate-glucuronosyltransferase 1A1 on the conjugation of bilirubin
- Quercetin inhibits cytotoxicity of PC12 cells induced by amyloid-beta 25–35 via stimulating estrogen receptor α, activating ERK1/2, and inhibiting apoptosis
- Nutrition intervention in the management of novel coronavirus pneumonia patients
- circ-CFH promotes the development of HCC by regulating cell proliferation, apoptosis, migration, invasion, and glycolysis through the miR-377-3p/RNF38 axis
- Bmi-1 directly upregulates glucose transporter 1 in human gastric adenocarcinoma
- Lacunar infarction aggravates the cognitive deficit in the elderly with white matter lesion
- Hydroxysafflor yellow A improved retinopathy via Nrf2/HO-1 pathway in rats
- Comparison of axon extension: PTFE versus PLA formed by a 3D printer
- Elevated IL-35 level and iTr35 subset increase the bacterial burden and lung lesions in Mycobacterium tuberculosis-infected mice
- A case report of CAT gene and HNF1β gene variations in a patient with early-onset diabetes
- Study on the mechanism of inhibiting patulin production by fengycin
- SOX4 promotes high-glucose-induced inflammation and angiogenesis of retinal endothelial cells by activating NF-κB signaling pathway
- Relationship between blood clots and COVID-19 vaccines: A literature review
- Analysis of genetic characteristics of 436 children with dysplasia and detailed analysis of rare karyotype
- Bioinformatics network analyses of growth differentiation factor 11
- NR4A1 inhibits the epithelial–mesenchymal transition of hepatic stellate cells: Involvement of TGF-β–Smad2/3/4–ZEB signaling
- Expression of Zeb1 in the differentiation of mouse embryonic stem cell
- Study on the genetic damage caused by cadmium sulfide quantum dots in human lymphocytes
- Association between single-nucleotide polymorphisms of NKX2.5 and congenital heart disease in Chinese population: A meta-analysis
- Assessment of the anesthetic effect of modified pentothal sodium solution on Sprague-Dawley rats
- Genetic susceptibility to high myopia in Han Chinese population
- Potential biomarkers and molecular mechanisms in preeclampsia progression
- Silencing circular RNA-friend leukemia virus integration 1 restrained malignancy of CC cells and oxaliplatin resistance by disturbing dyskeratosis congenita 1
- Endostar plus pembrolizumab combined with a platinum-based dual chemotherapy regime for advanced pulmonary large-cell neuroendocrine carcinoma as a first-line treatment: A case report
- The significance of PAK4 in signaling and clinicopathology: A review
- Sorafenib inhibits ovarian cancer cell proliferation and mobility and induces radiosensitivity by targeting the tumor cell epithelial–mesenchymal transition
- Characterization of rabbit polyclonal antibody against camel recombinant nanobodies
- Active legumain promotes invasion and migration of neuroblastoma by regulating epithelial-mesenchymal transition
- Effect of cell receptors in the pathogenesis of osteoarthritis: Current insights
- MT-12 inhibits the proliferation of bladder cells in vitro and in vivo by enhancing autophagy through mitochondrial dysfunction
- Study of hsa_circRNA_000121 and hsa_circRNA_004183 in papillary thyroid microcarcinoma
- BuyangHuanwu Decoction attenuates cerebral vasospasm caused by subarachnoid hemorrhage in rats via PI3K/AKT/eNOS axis
- Effects of the interaction of Notch and TLR4 pathways on inflammation and heart function in septic heart
- Monosodium iodoacetate-induced subchondral bone microstructure and inflammatory changes in an animal model of osteoarthritis
- A rare presentation of type II Abernethy malformation and nephrotic syndrome: Case report and review
- Rapid death due to pulmonary epithelioid haemangioendothelioma in several weeks: A case report
- Hepatoprotective role of peroxisome proliferator-activated receptor-α in non-cancerous hepatic tissues following transcatheter arterial embolization
- Correlation between peripheral blood lymphocyte subpopulations and primary systemic lupus erythematosus
- A novel SLC8A1-ALK fusion in lung adenocarcinoma confers sensitivity to alectinib: A case report
- β-Hydroxybutyrate upregulates FGF21 expression through inhibition of histone deacetylases in hepatocytes
- Identification of metabolic genes for the prediction of prognosis and tumor microenvironment infiltration in early-stage non-small cell lung cancer
- BTBD10 inhibits glioma tumorigenesis by downregulating cyclin D1 and p-Akt
- Mucormycosis co-infection in COVID-19 patients: An update
- Metagenomic next-generation sequencing in diagnosing Pneumocystis jirovecii pneumonia: A case report
- Long non-coding RNA HOXB-AS1 is a prognostic marker and promotes hepatocellular carcinoma cells’ proliferation and invasion
- Preparation and evaluation of LA-PEG-SPION, a targeted MRI contrast agent for liver cancer
- Proteomic analysis of the liver regulating lipid metabolism in Chaohu ducks using two-dimensional electrophoresis
- Nasopharyngeal tuberculosis: A case report
- Characterization and evaluation of anti-Salmonella enteritidis activity of indigenous probiotic lactobacilli in mice
- Aberrant pulmonary immune response of obese mice to periodontal infection
- Bacteriospermia – A formidable player in male subfertility
- In silico and in vivo analysis of TIPE1 expression in diffuse large B cell lymphoma
- Effects of KCa channels on biological behavior of trophoblasts
- Interleukin-17A influences the vulnerability rather than the size of established atherosclerotic plaques in apolipoprotein E-deficient mice
- Multiple organ failure and death caused by Staphylococcus aureus hip infection: A case report
- Prognostic signature related to the immune environment of oral squamous cell carcinoma
- Primary and metastatic squamous cell carcinoma of the thyroid gland: Two case reports
- Neuroprotective effects of crocin and crocin-loaded niosomes against the paraquat-induced oxidative brain damage in rats
- Role of MMP-2 and CD147 in kidney fibrosis
- Geometric basis of action potential of skeletal muscle cells and neurons
- Babesia microti-induced fulminant sepsis in an immunocompromised host: A case report and the case-specific literature review
- Role of cerebellar cortex in associative learning and memory in guinea pigs
- Application of metagenomic next-generation sequencing technique for diagnosing a specific case of necrotizing meningoencephalitis caused by human herpesvirus 2
- Case report: Quadruple primary malignant neoplasms including esophageal, ureteral, and lung in an elderly male
- Long non-coding RNA NEAT1 promotes angiogenesis in hepatoma carcinoma via the miR-125a-5p/VEGF pathway
- Osteogenic differentiation of periodontal membrane stem cells in inflammatory environments
- Knockdown of SHMT2 enhances the sensitivity of gastric cancer cells to radiotherapy through the Wnt/β-catenin pathway
- Continuous renal replacement therapy combined with double filtration plasmapheresis in the treatment of severe lupus complicated by serious bacterial infections in children: A case report
- Simultaneous triple primary malignancies, including bladder cancer, lymphoma, and lung cancer, in an elderly male: A case report
- Preclinical immunogenicity assessment of a cell-based inactivated whole-virion H5N1 influenza vaccine
- One case of iodine-125 therapy – A new minimally invasive treatment of intrahepatic cholangiocarcinoma
- S1P promotes corneal trigeminal neuron differentiation and corneal nerve repair via upregulating nerve growth factor expression in a mouse model
- Early cancer detection by a targeted methylation assay of circulating tumor DNA in plasma
- Calcifying nanoparticles initiate the calcification process of mesenchymal stem cells in vitro through the activation of the TGF-β1/Smad signaling pathway and promote the decay of echinococcosis
- Evaluation of prognostic markers in patients infected with SARS-CoV-2
- N6-Methyladenosine-related alternative splicing events play a role in bladder cancer
- Characterization of the structural, oxidative, and immunological features of testis tissue from Zucker diabetic fatty rats
- Effects of glucose and osmotic pressure on the proliferation and cell cycle of human chorionic trophoblast cells
- Investigation of genotype diversity of 7,804 norovirus sequences in humans and animals of China
- Characteristics and karyotype analysis of a patient with turner syndrome complicated with multiple-site tumors: A case report
- Aggravated renal fibrosis is positively associated with the activation of HMGB1-TLR2/4 signaling in STZ-induced diabetic mice
- Distribution characteristics of SARS-CoV-2 IgM/IgG in false-positive results detected by chemiluminescent immunoassay
- SRPX2 attenuated oxygen–glucose deprivation and reperfusion-induced injury in cardiomyocytes via alleviating endoplasmic reticulum stress-induced apoptosis through targeting PI3K/Akt/mTOR axis
- Aquaporin-8 overexpression is involved in vascular structure and function changes in placentas of gestational diabetes mellitus patients
- Relationship between CRP gene polymorphisms and ischemic stroke risk: A systematic review and meta-analysis
- Effects of growth hormone on lipid metabolism and sexual development in pubertal obese male rats
- Cloning and identification of the CTLA-4IgV gene and functional application of vaccine in Xinjiang sheep
- Antitumor activity of RUNX3: Upregulation of E-cadherin and downregulation of the epithelial–mesenchymal transition in clear-cell renal cell carcinoma
- PHF8 promotes osteogenic differentiation of BMSCs in old rat with osteoporosis by regulating Wnt/β-catenin pathway
- A review of the current state of the computer-aided diagnosis (CAD) systems for breast cancer diagnosis
- Bilateral dacryoadenitis in adult-onset Still’s disease: A case report
- A novel association between Bmi-1 protein expression and the SUVmax obtained by 18F-FDG PET/CT in patients with gastric adenocarcinoma
- The role of erythrocytes and erythroid progenitor cells in tumors
- Relationship between platelet activation markers and spontaneous abortion: A meta-analysis
- Abnormal methylation caused by folic acid deficiency in neural tube defects
- Silencing TLR4 using an ultrasound-targeted microbubble destruction-based shRNA system reduces ischemia-induced seizures in hyperglycemic rats
- Plant Sciences
- Seasonal succession of bacterial communities in cultured Caulerpa lentillifera detected by high-throughput sequencing
- Cloning and prokaryotic expression of WRKY48 from Caragana intermedia
- Novel Brassica hybrids with different resistance to Leptosphaeria maculans reveal unbalanced rDNA signal patterns
- Application of exogenous auxin and gibberellin regulates the bolting of lettuce (Lactuca sativa L.)
- Phytoremediation of pollutants from wastewater: A concise review
- Genome-wide identification and characterization of NBS-encoding genes in the sweet potato wild ancestor Ipomoea trifida (H.B.K.)
- Alleviative effects of magnetic Fe3O4 nanoparticles on the physiological toxicity of 3-nitrophenol to rice (Oryza sativa L.) seedlings
- Selection and functional identification of Dof genes expressed in response to nitrogen in Populus simonii × Populus nigra
- Study on pecan seed germination influenced by seed endocarp
- Identification of active compounds in Ophiopogonis Radix from different geographical origins by UPLC-Q/TOF-MS combined with GC-MS approaches
- The entire chloroplast genome sequence of Asparagus cochinchinensis and genetic comparison to Asparagus species
- Genome-wide identification of MAPK family genes and their response to abiotic stresses in tea plant (Camellia sinensis)
- Selection and validation of reference genes for RT-qPCR analysis of different organs at various development stages in Caragana intermedia
- Cloning and expression analysis of SERK1 gene in Diospyros lotus
- Integrated metabolomic and transcriptomic profiling revealed coping mechanisms of the edible and medicinal homologous plant Plantago asiatica L. cadmium resistance
- A missense variant in NCF1 is associated with susceptibility to unexplained recurrent spontaneous abortion
- Assessment of drought tolerance indices in faba bean genotypes under different irrigation regimes
- The entire chloroplast genome sequence of Asparagus setaceus (Kunth) Jessop: Genome structure, gene composition, and phylogenetic analysis in Asparagaceae
- Food Science
- Dietary food additive monosodium glutamate with or without high-lipid diet induces spleen anomaly: A mechanistic approach on rat model
- Binge eating disorder during COVID-19
- Potential of honey against the onset of autoimmune diabetes and its associated nephropathy, pancreatitis, and retinopathy in type 1 diabetic animal model
- FTO gene expression in diet-induced obesity is downregulated by Solanum fruit supplementation
- Physical activity enhances fecal lactobacilli in rats chronically drinking sweetened cola beverage
- Supercritical CO2 extraction, chemical composition, and antioxidant effects of Coreopsis tinctoria Nutt. oleoresin
- Functional constituents of plant-based foods boost immunity against acute and chronic disorders
- Effect of selenium and methods of protein extraction on the proteomic profile of Saccharomyces yeast
- Microbial diversity of milk ghee in southern Gansu and its effect on the formation of ghee flavor compounds
- Ecology and Environmental Sciences
- Effects of heavy metals on bacterial community surrounding Bijiashan mining area located in northwest China
- Microorganism community composition analysis coupling with 15N tracer experiments reveals the nitrification rate and N2O emissions in low pH soils in Southern China
- Genetic diversity and population structure of Cinnamomum balansae Lecomte inferred by microsatellites
- Preliminary screening of microplastic contamination in different marine fish species of Taif market, Saudi Arabia
- Plant volatile organic compounds attractive to Lygus pratensis
- Effects of organic materials on soil bacterial community structure in long-term continuous cropping of tomato in greenhouse
- Effects of soil treated fungicide fluopimomide on tomato (Solanum lycopersicum L.) disease control and plant growth
- Prevalence of Yersinia pestis among rodents captured in a semi-arid tropical ecosystem of south-western Zimbabwe
- Effects of irrigation and nitrogen fertilization on mitigating salt-induced Na+ toxicity and sustaining sea rice growth
- Bioengineering and Biotechnology
- Poly-l-lysine-caused cell adhesion induces pyroptosis in THP-1 monocytes
- Development of alkaline phosphatase-scFv and its use for one-step enzyme-linked immunosorbent assay for His-tagged protein detection
- Development and validation of a predictive model for immune-related genes in patients with tongue squamous cell carcinoma
- Agriculture
- Effects of chemical-based fertilizer replacement with biochar-based fertilizer on albic soil nutrient content and maize yield
- Genome-wide identification and expression analysis of CPP-like gene family in Triticum aestivum L. under different hormone and stress conditions
- Agronomic and economic performance of mung bean (Vigna radiata L.) varieties in response to rates of blended NPS fertilizer in Kindo Koysha district, Southern Ethiopia
- Influence of furrow irrigation regime on the yield and water consumption indicators of winter wheat based on a multi-level fuzzy comprehensive evaluation
- Discovery of exercise-related genes and pathway analysis based on comparative genomes of Mongolian originated Abaga and Wushen horse
- Lessons from integrated seasonal forecast-crop modelling in Africa: A systematic review
- Evolution trend of soil fertility in tobacco-planting area of Chenzhou, Hunan Province, China
- Animal Sciences
- Morphological and molecular characterization of Tatera indica Hardwicke 1807 (Rodentia: Muridae) from Pothwar, Pakistan
- Research on meat quality of Qianhua Mutton Merino sheep and Small-tail Han sheep
- SI: A Scientific Memoir
- Suggestions on leading an academic research laboratory group
- My scientific genealogy and the Toronto ACDC Laboratory, 1988–2022
- Erratum
- Erratum to “Changes of immune cells in patients with hepatocellular carcinoma treated by radiofrequency ablation and hepatectomy, a pilot study”
- Erratum to “A two-microRNA signature predicts the progression of male thyroid cancer”
- Retraction
- Retraction of “Lidocaine has antitumor effect on hepatocellular carcinoma via the circ_DYNC1H1/miR-520a-3p/USP14 axis”