Volume 41, Issue 69 -

The samples of Plasmopara halstedii (the causal agent of sunflower downy mildew) were collected on sunflower fields in south of the Russian Federation: in the Krasnodar, Rostov and Stavropol regions, and in the Republic of Adygea in 2016 and 2017. Virulence code of 545 isolates was identified; i. e. 280 isolates originating from 24 fields in 2016, and 265 isolates from 17 fields in 2017. Races 330, 334, 710 and 730, widespread within the region in previous years, were found in all mentioned areas. In addition, races 713, 733 and 734 have been detected in several districts of the Krasnodar region since 2016. This is the first report of these races in Russia and above that the first record throughout Europe and Asia for the races 733 and 734. The identification of new P. halstedii races was confirmed by the method of cross inoculations from individual differential lines. The phenotype corresponding to virulence code 734 was in some cases disclosed as a mixture of race 334 with 710 or 730. The presence of several P. halstedii races on an individual plant was also confirmed for the first time in the territory of the Russian Federation.

Genetic makeup along with environmental stimuli affect the expression of a trait in plants. Drought tolerance in addition to stability of characters over a wide range of environmental conditions is not well studied in sunflower. Therefore, here we have performed a stability analysis study of sunflower genotypes. The experimental material comprised of 19 lines of sunflower comprising 9 alloplasmic cms lines from different wild sources along with one common maintainer from petiolaris source, 4 cms lines and one maintainer from cultivated source (cytoplasm from H. petiolaris ), 4 restorer lines and 60 F 1 hybrids (developed in line x tester design). The experiment was conducted over two years i. e. spring season 2011 and spring season 2012 over the two environments one normal irrigated and another water stress environment at Punjab Agricultural University, Ludhiana, India. The data were recorded for different morphophysiology, yield and quality trais and analysis as per standard procedures. The genotype×environment interaction was further partitioned into linear and non-linear components according to Eberhart and Russel model. Eleven sunflower hybrids were found to be stable across the environments for seed yield. While, sufficient variability was also recorded for the oil content with the highest oil percentage in the cross combination ARG-2A×P100R (34.61). Overall, this study provides useful information regarding the stability of newly developed and cytoplasmically diverse sunflower hybrids under north Indian conditions.

Sixteen sunflower hybrids obtained by crossing between four CMS and four restorer lines as tester were evaluated for combining abilities of agronomic traits under optimum and water limited conditions using line×tester mating design. There was considerable variability among genotypes for the traits in both normal and stressed experiments. The results indicated that the lines AGK344 and AGK148 with suitable GCA for early maturity and plant height respectively and AGK52 for oil content and seed and oil yield were desirable combiner under both optimum and stressed condition. In other hand, AGK344 expressed a significant GCA for plant height in suitable direction under stressed condition. Among the testers RGK26 and RGK56 had suitable GCA for days to maturity under both conditions. RGK56 and RGK26 were appropriate combiner for oil content under optimum and water stressed conditions respectively the later had desired GCA for seed and oil yield under water stressed condition too. According to the results, there was differentiate GCA of testers for days to flowering, seed weight and oil content in normal and stressed condition. Differential expressions of GCA in parent inbred lines indicated that selection of restorer lines for the agronomic traits would be more efficient than the selection of CMS lines. It is concluded that heritability of a trait determines the kind of SCA in response to different environments and the SCA effects are more stable for traits with higher heritability.

Present study is performed to evaluate the effects of foliar application of salicylic acid, glycine betaine, ascorbic acid, nano-silica and nano titanium dioxide on yield and yield component of sunflower. Chlorophyll content, leaf length, leaf width, days to 50 % flowering, day to maturity, plant height, husk percentage, number of seeds per head, head number per plant, percentage of empty achenes, 1000-seed weight, kernel weight, grain length, straw yield, harvest index, grain yield and oil percent were measured. Results showed that the first two principal components accounted 49 % and 19 %, respectively of sums of squares of the TT interaction and were used to create a two-dimensional treatment by trait (TT) biplot. The vertex treatments in polygon of TT biplot were ascorbic acid, glycine betaine, nano-TiO 2 and control which Nano-Ti 2 treatment indicated high performance in chlorophyll content, day to maturity, number of seeds per head, head number per plant, kernel weight, grain length, straw yield, harvest index, grain yield and oil percent. The identification of ideal treatment, the treatment that is most favorable treatment among all treatments, showed that the nano-TiO 2 might be used in selecting superior traits and it can be considered as the candidate treatment. Treatments suitable for obtaining of high seed yield were identified in the vector-view function of TT biplot and displayed nano-silica and nano titanium dioxide as the best treatments suitable for obtaining of high seed yield. In short, nano-fertilizer could increase crop yields and improve the fertilizer efficiency.

In the Russian Federation the most favorable area for high and stable yields of sunflower crop is the Northern zone of Krasnodar region. The research was conducted in multivariate experience of long-term stationary monitoring. We researched the effect of doses of mineral fertilizers and furolan on sunflower yield and seed quality. It was found that it is expedient and cost-effective to use small doses of nitrogen fertilizers for sunflower. The expediency of application of plant growth regulator (Furolan) during vegetation is shown. We found that the use of mineral fertilizers and the use of furolan contributed to the activation of growth processes of sunflower plants which led to the formation of optimal plant density. Improving the nutritional status of plants has provided an increase in the leaf area unit. The treatment of sunflower crops on the background of fertilizers N 20 P 30 and the furolan has had a positive impact on the value of photosynthetic potential. Under the influence of mineral fertilizers there was an increase in the dissemination of the sunflower head, weight of seeds and weight of 1000 seeds, which has a positive impact on productivity. With the increase of fertilizer doses, the oil content of seeds increased when compared to the unfertilized variant. The treatment of plants with furolan has not violated the process of accumulation of protein and fat.

This study was performed to study the effects of farmyard manure (zero (M1), 20 (M2) t ha −1 ) and nano-fertilizers [control (n1), Mn (n2), Fe (n3), Zn (n4)] on sunflower. Traits days to 50% flowering, days to maturity, leaf number, leaf area, plant height, achene yield and harvest index were measured.Treatment by trait (TT) analysis using biplot analysis was used to determine which treatment was best and for what trait which were generated using the standardized values of the traits means. Results showed that the first two principal components (PC1 and PC2) were used to create a two-dimensional TT biplot that accounted percentages of 94% of sums of squares of interaction. The most important vertex treatment in polygon of TT biplot was M2n4 (application of 20 tonnes ha −1 manure and Zn nano-micronutrient) which indicated high performance in leaf number, leaf area, plant height, achene yield and harvest index. The identification of ideal treatment, the treatment that is most favorable treatment among all treatments, showed that the M2n4 might be used in selecting superior traits and it can be considered as the candidate treatment. Finally, nano-fertilizer could increase crop yields and improve the efficiency of manure application. The results of this investigation showed that application of nanoparticles may alleviates the adverse environmental factors and improve the sunflower performance and the integrated application of organic manure and nano-micronutrients is more effective.

Sunflower is an important source for edible oils and biodiesel production. Its productivity is limited by many agronomical practices one of which is the sowing date. In this study, the effects of different sowing dates from early April to late June on phenology and yield of sunflower cultivars were investigated. The results showed that sunflower has a relatively long period of possible sowing dates, stretching from early April to late June in North West of Iran. However, delayed sowing dates significantly decreased the number of days needed for phenophases. For every day of delay, the model predicted (R 2 =0.97) a losing rate in achene yield by 22.2 kg h −1 from the first sowing date. For relationships between growing degree days (GDD) and yield, almost the same results were obtained. About 22 kg h −1 reduction (R 2 =0.79) in yield per day was estimated by GDD index when the average GDDs per day was 14.2. However, helio-thermal units (HTU) did not predict this reduction accurately. A suggested comprehensive model, that used the percent of yield losses and changes in vegetative to reproductive ratio, found a significant and positive relationship between the indices and yield losses. For all indices, an increase in vegetative to reproductive ratio resulted in increased grain yield losses.

Imisun sunflowers ( Helianthus annuus L.) are imidazolinone-resistant cultivars in which the two mechanisms of herbicide resistance coexist: (i) mutation in herbicide target-site (target-site resistance) and (ii) non-target-site resistance (NTSR). In Imisun technology, NTSR could be related to herbicide metabolism and might occur as a result of a constitutive up-regulation of resistance genes, or it can appear only after herbicide treatment. The objective of this study was to characterize NTSR in Imisun sunflower in response to imazethapyr using RNA-Seq and to determine whether these mechanisms are constitutive or herbicide-induced. Cypsels were germinated in plastic pots, watered by capillarity and growth in chamber under controlled conditions. Seven-day-old plants were treated with 0 (control) and 1 μM imazethapyr for 12 h. After leaf RNA purification, stranded, paired-end cDNA libraries were constructed. Sequencing was performed with Illumina HiSeq2000. Local mapping, with and without multihits, was carried out over the reference transcriptome HaT13l and differential expression was analysed. Sixty one and 47 contigs (according to mapping strategy) related to xenobiotic metabolism were found: cytochromes P450s, ABC transporters, glycosyltransferases, UDPglucuronosyl/glucosyltransferases and glutathione S-transferases. None of these contigs showed differential expression between control and imazethapyr-treated plants. Seventeen interesting contigs were verified by qRT-PCR. These results suggest that constitutive NTSR mechanisms may account for imidazolinone resistance in Imisun sunflower.