Effects of Salt Stress on Absorption And Distribution of Osmotic Ions in Wheat Seedlings

Effects of salt stress on absorption and distribution of osmotic ions in wheat seedlings were studied with 4 winter wheat varieties under NaCl stress by exploring dynamic changes of Ca2+, K+, Na+, Ca2+/Na+, K+/Na+ and Na+ limiting ability. The results showed that the contents of K+, Ca2+ and the K+/Na+ ratio gradually decreased in a manner of both salt concentration dependent and stress time dependent. The extent of reduction of K+ and Ca2+ in root was much more severe than that in shoot. The ability of Na+ limiting in QM6 and DK961 was stronger than that in JM22 and QF1. These results indicate that the maintenance of higher Na+ content in root, Na+ limiting ability, Ca2+ and K+ concentration will be the main physiological traits for the salt-tolerance of wheat. Bangladesh J. Bot. 50(4): 1209-1214, 2021 (December)

Ecological trial of the winter wheat varieties of the ARC “Donskoy” in the area of dark chestnut soils of the Volgograd region

The current paper has presented the trial results of the winter wheat varieties developed by the ARC “Donskoy” in 2018 -2020. Currently, the farmers have bred a lot of different wheat varieties, but they are not able to take into account all the peculiarities of their cultivation. The purpose of the current work was to study the features of the autumn and spring-summer vegetation periods of the winter wheat varieties developed by the ARC “Donskoy” in the area of dark chestnut soils of the Volgograd region. There have been selected 10 winter wheat varieties for the trials. The field trial was laid down on dark chestnut soils of the lands of the Serafimovichsky district in the Volgograd region. The study was carried out according to the generally accepted B.A. Dospekhov’s methodology. The field trials showed that the germination of winter wheat was influenced by a seeding depth, which was 7-9 cm. The best germination was found among the varieties ‘Asket’, ‘Etyud’, ‘Lilit’, ‘Donskaya Step’ and ‘Zhavoronok’. During the trials, the formation of a productive stand was greatly influenced by the weather (the length of a spring tillering period, precipitation in May), as well as the traits of the variety. The winter wheat varieties ‘Etyud’, ‘Shef’, ‘Donskaya Step’, ‘Krasa Dona’ were able to form a large number of productive stems under favorable weather conditions. Under insufficient moisture supply, the largest number of productive stems was formed by the varieties ‘Lidiya’ and ‘Lilit’. The highest tillering intensity during an autumn vegetation period was shown by the variety ‘Lidiya’ (4.7–6.2 shoots), including the varieties ‘Zhavoronok’ (4.2–5.4 shoots) and ‘Etyud’ (4.0–5.3 shoots). The largest productivity was produced by the varieties ‘Donskaya Step’ (4.97 t/ha), ‘Zhavoronok’ (4.95 t/ha), ‘Krasa Dona’ (4.90 t/ha) over three years.

Sowing dates and their effect on productivity and grain quality of the winter wheat varieties

The analysis of the Crimean weather conditions during the autumn vegetation period of winter wheat indicates climate warming and, in this regard, the necessity to adjust the optimal sowing dates. The purpose of the current study was to estimate the productivity and grain quality of winter bread wheat varieties depending on different sowing dates. The objects of the study were five winter wheat varieties sown in 5 dates from October 1 to November 30 with an interval of 15 days. Field trials were conducted with appropriate observations, records, measurements and analyzes, according to the methodology of the State Variety Testing. Statistical processing of the trials was carried out by the B.A. Dospekhov’s method of dispersion and correlation analyzes. The study was carried out through three years, two vegetation periods of which (2017–2018 and 2019–2020) were dry, one period (2018-2019) was favorable for the development of winter grain crops. According to the results of the analysis of variance, there have been identified significant differences in the effect of all three factors (‘variety’, ‘length’ and ‘year’) and their correlation in all combinations on the productivity formation. The factors ‘sowing date’ (33%) and ‘correlation between date and year’ (49%) had the greatest influence on the productivity formation. In 2018, the most optimal for all studied varieties was the second sowing date (15.10), in 2019 it was the first (1.10), and under the conditions of 2020, the later sowing dates were more favorable, and the 4th period was marked as optimal (15.11). The mean productivity of all varieties at the optimum sowing dates was 4.0; 5.5 and 3.46 t/ha, respectively. The factors ‘sowing date’, ‘year’, and the correlation between them significantly influenced protein percentage in grain. Their effect on the manifestation of the above trait was 29%, 14% and 23%, respectively; on gluten content it was 29%, 16% and 21%, respectively.

Transgressive variability in the number of ears of the main spike in F2 populations when crossing soft winter wheat varieties of different early maturity.

Aim. Determination of the degree and frequency of positive transgressions by the number of ears of the main spike in F2 populations created by crossing varieties of soft winter wheat of different maturity depending on the hydrothermal conditions of the year and selection of economically valuable biotypes for subsequent breeding work. Methods. Field, laboratory, mathematical and statistical. Results. In the majority of F2 populations, created by hybridization of soft winter wheat varieties of different vegetation periods, a significant form-making process took place in terms of the number of spikelets in the main spike. The experimental data obtained indicate a significant effect of matched pairs before hybridization and hydrothermal conditions of the year on the manifestation and formation of the number of spikelet’s in an ear F2. So, under the conditions of 2019, the majority of F2 populations for the number of spikelet’s in the main spike (17.4–21.5 pcs.) Significantly exceeded the parental forms. A positive degree (Td = 5.3–33.3 %) and the frequency of transgression (Tf = 3.3–96.7 %) were found in 85.7 % of the populations. In 2020, the average population number of spikelets in the main spike (15.0–18.6 pcs.) Was significantly less. When used in hybridization of early maturing varieties by the parent form, the decrease in the number of spikelets was 0.5–19.9 %. At the same time, for crossing mid-early, mid-ripening and mid-late varieties, the number of spikelets decreased by 2.8–28.9 %. Thus, it can be argued that populations in which early maturing varieties were the maternal form are less exposed to unfavorable conditions of the year. A positive degree (Td = 5.3–38.9 %) and the frequency of recombinants (Tf = 3.3–46.7 %), under the conditions of 2020, was established in 35 out of 42 F2 populations, which amounted to 83.3 %. Conclusions. The use of winter wheat varieties of different early maturity in hybridization in most cases contributes to the formation of F2 in populations and the selection of positive transgressive biotypes by the number of spikelets in the main spike. Conducted studies have established a significant effect of the parental forms used in hybridization and the hydrothermal conditions of the year on the formation of the number of spikelets in the main spike in F2 populations of soft winter wheat. Populations where the early maturing varieties were the maternal form are characterized by a more stable manifestation of the number of spikelets in the main spike. The decrease in the number of spikelets in 2020 compared to 2019 was 0.5–19.9 % for 2.8–28.9 % in populations obtained by hybridization of mid-early, mid-ripening and mid-late varieties. In years with contrasting hydrothermal conditions, hybrid populations F2 were identified, which formed more than the average F2 number of spikelets in the main spike and had high rates of the degree and frequency of positive transgressions, namely: Mironovskaya early / Kolchuga; Kolchuga / Stolichnaya; Shchedraia niva / Vidrada; Antonovka / Stolichnaya.

TREND, POPULATION STRUCTURE AND TRAIT MAPPING FROM 15 YEARS OF NATIONAL VARIETAL TRIALS OF UK WINTER WHEAT

There are now a rich variety of genomic and genotypic resources available to wheat researchers and breeders. However, the generation of high-quality and field-relevant phenotyping data which is required to capture the complexities of gene x environment interactions remains a major bottleneck. Historical datasets from national variety performance trials (NVPT) provide sufficient dimensions, in terms of numbers of years and locations, to examine phenotypic trends and study gene x environment interactions. Using NVPT for winter wheat varieties grown in the UK between 2002 – 2017, we examined temporal trends for eight traits related to yield, adaptation, and grain quality performance. We show a non-stationary linear trend for yield, grain protein content, HFN and days to ripening. Our data also show high environmental stability for yield, grain protein content and specific weight in UK winter wheat varieties and high environmental sensitivity for Hagberg Falling Number. We also show that UK varieties released within this period cluster into four main population groups. Using the historical NVPT data in a genome-wide association analysis, we uncovered a significant marker-trait association peak on wheat chromosome 6A spanning the NAM-A1 gene that have been previously associated with early senescence. Together our results show the value of utilizing the data routinely collected during national variety evaluation process for examining breeding progress and the genetic architecture of important traits.

Identification of drought resistance of winter bread wheat varieties and lines by vegetation and laboratory methods

The article discusses the impact of severe drought on the growth and development of winter wheat plants. The studies were carried out in 2018-2020. As a starting material, we used 57 samples of winter soft wheat bred by ARC “Donskoy”. The studies were carried out under laboratory and vegetation methods. According to the analysis, it was revealed that the highest values of the index of complex resistance were shown by the samples: intensive type - 1630/17 (282.8 rel.units), 2078/16 (265.1 rel.units), 1990/17 (265, 0 rel.units); semi-intensive type -1727/17 (260.6 rel. units), 2243/17 (258.6 rel. units), 522/16 (252.8 rel. units). The maximum value of the degree of drought resistance of samples of the intensive type was noted for lines 2243/17 (92.4%), 1727/17 (84.9%), and 522/16 (82.6%). Among 36 samples of winter soft wheat of intensive type, high drought resistance was noted in 67% (24 samples) with germination from 71.6 (Univer) to 92.9% (1630/17). High values of heat resistance (I-81-100% of germination) out of 57 studied samples of winter wheat were noted in 56 genotypes, the indicators of which ranged from 85.1% (1181/16) to 98% (Zodiac, 1166/15, 1275/16). The highest grain yield under model drought conditions was noted for winter wheat varieties Zodiac (332.86 g/m2), Premiera (332.48 g/m2) and Podarok Krymu (317.50 g/m2), which is higher than the yield of the Ascet classifier (292.97 g/m2) by 8.0-13.7%..

Phenolic Compounds in Organic and Conventional Winter Wheat (Triticum aestivum L.) Wholemeal

Winter wheat wholemeal is an important component of the human diet and may be a significant source of antioxidants. The objective of this study was to determine individual phenolic compounds in five winter wheat varieties: ‘Fredis’, ‘Edvins’, ‘94-5-N’, ‘Skagen’, and ‘SW Magnific’ wholemeal, grown according to organic and conventional agricultural practices. Ten phenolic compounds (vanilin, rutin, catechin hydrate, quercetin, p-coumaric acid, ferulic acid, 3.4-dihydroxybenzoic acid, 2-hydroxycinnamic acid, trans (3)-hydroxycinnamic acid, and gallic acid) were detected using high-performance liquid chromatography (Schimadzu Prominence HPLC). Catechin hydrate and quercetin were the main phenolic compounds in the grain of all tested winter wheat varieties. Significant differences (p < 0.05) among the analysed winter wheat cultivars in the concentration of individual phenolic compounds were observed. Concentrations of vanillin in organic and conventional winter wheat wholemeal were significantly lower (0.28 ± 0.02 to 0.65 ± 0.04 µg·g−1 DW), although the differences in the levels of phenolic were not large. The obtained results showed a statistically significant trend (p < 0.05) towards higher levels of phenolic compounds in organic wheat wholemeal samples.

Fusarium diseases of sunflower and wheat in Tambov region

The study of prevalence and species composition of Fusarium fungi on sunflower and winter wheat crops was carried out in Tambov region. In 1992-2020, 15 Fusarium fungi were identified on sunflower crops. It was identified that the predominant species infecting sunflower plants and seeds are Fusarium oxysporum, F. oxysporum var. orthoceras, F. verticillioides, and F. tricinctum. The prevalence of these pathogens was 16.3-21.8%. On the grain of winter wheat, Fusarium poae, F. equiseti and F. sporotrichioides were more common (19.6-28.6%). It was found that the seeds of Lgovskaya 8, Don Awnless and Don’s Governor were less affected by fusarium infection (by 3 - 4%). It was observed that Fusarium fungi are associated with certain winter wheat varieties. Research results may be useful for specialists studying diseases of sunflower and wheat.