Variety Trials Research Articles

Using Partial Least Squares and Regression to Interpret Temperature and Precipitation Effects on Maize and Soybean Genetic Variance Expression

Partial least squares (PLS) is a statistical technique that can evaluate the association of large numbers of external environmental variables with biological responses. PLS is a good method for analyzing the relative importance of variables and compressing the data for regression analyses. The objective of this study was to use PLS and regression analyses on soybean (Glycine max L.) and maize (Zea mays L.) variety trial results for five (soybean) or three (maize) maturity group (MG) tests, at five Tennessee locations spanning 14 years, in order to determine the environmental effects (weekly minimum and maximum air temperature and precipitation) on the expression of yield genetic variance (Vg). Overall, PLS excelled at identifying combinations of weather variables to develop models with high R2 values (41–59%) relative to the regression analysis (R2 = 34–44%), but they did not address the effects of specific variables as in regression analysis. In both maize and soybean, differences in genetic variance occurred among MG tests and locations. Overall, precipitation was the driving variable for maize Vg, indicating maize is more sensitive to rain events during the growing season than soybean, i.e., with each cm of precipitation, maize Vg increased by 11.38–23.78 (Mg ha−1)2. The results suggest that ensuring adequate water, particularly during weeks 3 and 6, is critical for maize Vg, regardless of the MG test and location. Genetically modified soybean cultivars responded similarly to conventional cultivars, suggesting no Vg response differences due to the glyphosate tolerance trait. These results have important implications for irrigation timing for the maximum expression of genetic differences in maize and soybean cultivars, particularly for management planning during future stochastic weather events.

Introduced resistant grape variety Frontenac Blanc

Th e paper presents a variety trial and technological evaluation of the wine material from Frontenac Blanc grape, isolated as a color mutation in Canada plantations of the Frontenac Gris variety in 2006. Th e study was carried out in 2020–2022 in compliance with vitiviniculture recognized methodology in soil and climatic conditions of Potapenko All-Russian Research Institute of Viticulture and Winemaking, a branch of Federal Rostov Agrarian Scientifi c Centre, Novocherkassk, Rostov Oblast, Russia. Vineyards are open-earth, rainfed, graft ed, with Kober 5BB rootstock, 3.0×1.5 m planting scheme, shaping: double-shouldered low (40 cm) horizontal cordon, short pruning on knots. Agricultural technology is standard, generally recognized. Frontenac Blanc is found to obtain high winter hardiness, promising for open-earth cultivation. Th e variety has good resistance to infections: to mildew (2.0 score), oidium (2.5 score); grey rot has not been observed. Th erefore, frequent use of pesticides is not required and vineyard maintenance is simplifi ed. Th e high level of sugars (248 g/dm3) and t itratable acids (10.4 g/dm3) in t h e juice ensures a harmonious wine with well-balanced acidity. Due to such characteristics, the variety is considered to be promising for the production of diff erent wine styles, including dry still, semi-dry, as well as sparkling and liqueur wines. Th e wine material from Frontenac Blanc presents a distinguishing character, bright fruit aromas, rich structured fl avor, and lingering fi nish. Th e average tasting score of the wine material comprises 8.6 points (on a 1–10 scale). Th e variety has a high yield (16 tonnes/ha), which does not adversely aff ect the quality of products. Frontenac Blanc is resistant to cold and early ripening period (120 days) and can be eff ectively grown in regions with previously limited production due to extreme climatic conditions. Considering that, an innovative development of the wine industry in areas with cool and uncertain climate possesses a high potential.

Triticale in Italy.

Triticale is currently grown throughout the world with a wider diffusion in Europe, with Poland, Belarus, Germany, France and Spain as major producers. Although triticale occupies a very small fraction of the Italian cultivated land (16,000 ha of harvested area, mean value of the past 5 years), a continuous interest for this crop and its possible uses explains the work and progress made by breeding activities in different periods. The aim of this review is to report some experiences related to the cultivation of triticale in Italy. A general long-term view of the performance of triticale varieties in Italy has been distilled from a large amount of data derived from the pluri-decennial Italian national variety trials network. This activity, historically coordinated by CREA-GB, extends over several decades and examines the agronomic performance, in different Italian environments, of the most widespread and emerging varieties of triticale. Indications on new breeding targets can be deduced from the elaborations in the frame of both climatic change and market demands.

Exploring the trait‐yield association patterns in different oat mega‐environments of Canada

AbstractThis article presents a graphical method to visually analyze the trait–yield association (TYA) patterns based on data from multi‐location, multi‐year crop variety trials, exemplified using oat data from trials conducted across Canada from 2017 to 2022. Each year a new set of 60–66 oat (Avena sativa L.) breeding lines were tested in replicated yield trials at 9–11 locations, and data for yield, key agronomic and quality traits, and crown rust scores were collected at all or some of the locations. Pearson correlation coefficient was calculated between yield and each trait for each trial. The correlation coefficients from different locations and years were arranged in a TYA × trial (TYT) two‐way table. This table was subjected to singular value decomposition, and the resulting first two principal components were used to generate a TYT biplot. The TYT biplot revealed three oat mega‐environments (MEs) in Canada, consistent with the conclusion from previous ME analyses, indicating that each ME had its characteristic TYA patterns. It was found that yield was consistently and positively correlated with crown rust (Puccinia coronata var. avenae) resistance, test weight, kernel weight, and groat content in ME1 (the crown rust‐prone regions of Ontario); yield was correlated positively with plant height but negatively with oil content in ME2 (the northern regions of eastern Canada). Interestingly, crown rust resistance was found to contribute negatively to yield in ME2. No strong and consistent TYAs were found in ME3 (the Canadian prairies). Different types of TYAs have different uses in genotypic selection.

Adaptability Evaluation of White Fleshed Sweet Potato Variety Trial at Silte and Gurage Zones, Ethiopia

Adaptability Evaluation of White Fleshed Sweet Potato Variety Trial at Silte and Gurage Zones, Ethiopia

Association Between Dominant Wheat Stem Rust Races Found in Ethiopia and Grain Yield in Advance Bread Wheat Genotypes

The study was conducted in 2019 and in 2020 across two locations: Dhera and Asasa in Ethiopia to study the correlation between dominant stem rust races found in Ethiopia and grain yield on bread wheat genotypes found in the national wheat research program pipelines. Twenty three bread wheat genotypes and two released bread wheat varieties set as a Bread Wheat National Variety Trial by the national wheat research program for low altitude and planted at Dhera and Asasa. A square lattice design with two replications used for experiment conducted on the field. A plot of six rows, size of 2.5 m by 1.2 m, and a total area of 3 m2 used. The same genotypes planted using complete randomized design in three replications at Kulumsa Agricultural Research Center green house. Seven-day old seedlings were inoculated with spores of selected races: TTTTF, TKTTF, TKKTF, TTRTF and BULK. Data on infection types (IT) were recorded 14 days after inoculation using 0–4 scale. Result in the study revealed that Grain yield had positive genotypic association with all four races but bulk at Dhera. A very high negative significant genotypic correlation r=-0.708*** obtained between Grain yield and field Stem rust diseases score at Asasa. Those genotypes carrying race-specific effective gens for the races used in the green house were resistance at the seedling stage. But, on the field, at the adult stage, they lost the resistance and become susceptible.

Comparative demonstration trials of winter wheat varieties of the ARC “Donskoy” in the zone of blackearth soils of the Volgograd region

The current paper has considered the results of comparative trials of winter wheat varieties of the ARC “Donskoy” in the zone of blackearth soils, the subzone of southern blackearth of the Volgograd region. Modern breeding provides a wide choice of winter wheat varieties. In the Volgograd region, more than 100 varieties are sown annually. This objectively results in difficulty of the best choice. Based on the official data on the preferences of farmers, there have been optimized the selection base, focusing on the varieties of the ARC “Donskoy”, considering it more important and responsible for farmers to clarify information about this significant (about 60 %) block. The field trial was laid in the Kikvidzensky district of the Volgograd region in the zone of blackearth soils, the subzone of southern blackearth, on the lands of “AGROPRODUKT” LLC. The study was carried out according to the methodology used by the State Variety Commission. Significant effect on the autumn stage of development was made by weather conditions, which were significantly contrasting, during the years of trial. The value of field germination was at the level of 65–75 %. The indicators of autumn tillering at the end of the autumn vegetation period for three years were in a rather narrow range of 3.9–4.7 pcs/plant. In the studied area, the formation of yield due to the density of productive stems prevailed. On average, for three years, the value of the productive stalk was 610–729 pieces/m2. According to this indicator, the winter wheat varieties ‘Krasa Dona’, ‘Donskaya Step’, ‘Kapitan’ (679–729 pcs/m2) were the best ones. As a result, the best productivity indicators were demontarted by the varieties ‘Krasa Dona’ (5.66 t/ha) and ‘Donskaya Step’ (5.41 t/ha). A significant group of varieties, such as ‘Kapitan’, ‘Lidiya’, ‘Asket’, ‘Zhavoronok’, formed 5.21– 5.26 t/ha.

The spring durum wheat variety ‘Bezenchuksky Podarok’

The purpose of the current study was to determine the main economically valuable traits of the new spring durum wheat variety ‘Bezenchuksky podarok’, to establish its significance in the system of durum wheat varieties and to describe the main approbation traits. The variety was developed by individual selection from the hybrid population F9 746D-39/Pamyati Chekhovicha. Its pedigree includes such varieties as ‘Kharkovskaya 46’, ‘Bezenchuksky yantar’, ‘Saratovskaya zolotistaya’, ‘CIMMYT – Altar 84’, ‘Ahninga’, intermediate breeding lines ‘92D-4’, ‘2125D-4’, ‘746D-18’ of the Samara RIA and the breeding line ‘358s-94’ of the RIA of the South-East. Field trials, phenological observations and estimations in the competitive and ecological variety trials were carried out in accordance with the requirements of the methodology of the State Commission for Variety Testing and Protection of Breeding Achievements. The variety belongs to the Volga steppe ecological group, middle-maturing biotype, having a medium-sized stem (with the height reduction gene RhtAhng). Over the years of study (2018–2022), in the competitive variety testing, a new variety with a mean grain productivity of 2.36 t/ha exceeded the standard variety ‘Bezenchukskaya 210’ on 0.15 t/ha and the variety ‘Bezenchukskaya zolotistaya’, which is widespread in the Volga region and the Urals, on 0.19 t/ha. In the ecological variety testing in the Samara SAU (Kinel) and in the RIA of the South-East (Saratov), the excess over local standards was 1.05 t/ha and 0.06 t/ha, respectively. In the competitive variety testing (2018–2022), the new variety was the best in its responsiveness to environmental conditions (the regression coefficient bi was 1.06, the standard variety’s coefficient was 1.00), and its resistance to stem rust pathogens and leaf spots (Alternaria sp., Fusarium sp.). The new variety was the best in terms of gluten quality with the parameters of SDS (52 ml), and IG (94.0 %), which makes it possible to attribute it to the class of durum wheat varieties with excellent gluten. Thus, gluten quality and production capabilities of the variety ‘Bezenchuksky Podarok’ have enhanced the diversification of the durum wheat varietal system in the Middle Volga region.

Continuing genetic improvement and biases in genetic gain estimates revealed in historical UK variety trials data

ContextThe current pace of yield increase for major crops is not fast enough to meet future demand. Crop breeding programmes are under increasing pressure to improve existing crops further. Quantifying the contribution of these programmes to observed yield increases is important for evaluating their success and identifying if crop improvement goals are likely to be met. ObjectiveIn this paper we explore methods to study the genetic gain of two cereal species, wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). Specifically, the objective of this research was to identify sources of bias in genetic gain estimates of UK variety trials data. MethodsGenetic gain was estimated for fungicide-treated and untreated UK winter wheat, winter barley and spring barley for 1982–2018 using UK National List and Recommended List variety trials data. Subsets of the winter wheat variety trials dataset were used to replicate shorter breeding cycles to quantify the impact of the number and choice of long-term check varieties on estimating genetic gain. ResultsWhile genetic and non-genetic contributions to changes in UK cereal performance are in line with previous estimates, we were able to identify previously undetected changes and biases in estimates of variety performance. Specifically, we observed an increasing yield difference between fungicide treated and untreated variety trials as varieties age, driven by both a breakdown in disease resistance and a previously unobserved long-term increase in yield as varieties age in treated trials. This shows that yields of long-term check varieties cannot be assumed to be stable over time. We found that genetic gain estimates were highly sensitive to the long-term check varieties chosen, whilst the inclusion of multiple checks decreased the standard error of the estimate. ConclusionThe estimation of genetic gain is highly susceptible to bias. We provide recommendations on how to reduce the risk of bias for estimating genetic gain. ImplicationsAccounting for sources of bias in genetic gain calculations is important in any programme of selection to prevent inaccurate quantification of yield progress.

Predicting Nutritional Quality of Dual-Purpose Cowpea Using NIRS and the Impacts of Crop Management

Cowpea fodder has been one of the favored livestock forages for centuries in sub-Saharan Africa, particularly in Senegal. However, little research has been conducted on quantifying the nutritional quality of cowpea fodder because of the costly wet chemistry analysis. The main objective of this study was to develop predictive equations for a sustainable quantification of the nutritional quality of dual-purpose cowpea fodder using near infrared spectroscopy (NIRS) and to investigate the influence of cropping system, fertilizer, genotype, and their interaction on biomass yield and cowpea forage nutritional value. In this study, 120 samples from a dual-purpose cowpea variety trial were used to develop NIRS equations to estimate forage quality parameters including concentrations of crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), calcium (Ca), phosphorus (P), potassium (K), and iron (Fe). Partial least squares (PLS) regression generated prediction equations using NIRS wavelength measurements, and reference wet chemistry analysis from calibration samples were developed. The PLS prediction equations for the different forage quality parameters had an R2 of calibration 0.94, 0.93, 0.88, 0.63, 0.69, 0.87, and 0.94 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. Using these prediction equations, correlation of the predicted values of the calibration subset and the prediction test subset resulted in significant positive relationships, with R2 of 0.83, 0.74, 0.70, 0.63, 0.59, 0.75, and 0.83 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. The corresponding RMSE of these relationships was 0.91, 2.68, 3.45, 0.23, 0.06, 0.11, and 100 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. The range and mean concentrations of the calibration subset overlapped with that of the prediction subset for all parameters evaluated. Cross-validation procedures indicated good correlations between wet chemistry analysis and NIRS forage quality estimates. Results of the second experiment showed that the cropping system had no significant effect on cowpea forage yield and nutritive value. However, cowpea variety and fertilizer, both individually and their interaction, had a significant effect on fodder yield and cowpea forage quality. We conclude that the NIRS calibration equations developed can be used to accurately predict the cowpea forage quality parameters evaluated in this study.

BRRI dhan104: BRRI’s Basmati Type Aromatic Rice Variety for Irrigated Ecosystem in Bangladesh

An enhancement over already available premium quality enriched aromatic rice varieties for Bangladesh is the recently announced BRRI dhan104 type of rice, which has long slender grain and is high yielding and ideal for Bangladesh's irrigated ecology. The variety has satisfactorily passed the Proposed Variety Trial (PVT) conducted in the farmers’ field in Boro 2021-22 season. As a result National Seed Board (NSB) approved this variety for commercial cultivation in the Boro season (dry season) in 2022. It has modern plant type with 92 cm plant height and matures by 147 days. The proposed variety showed 0.68 t/ha higher yield than check variety BRRI dhan50. Identifying characters of this variety are green leaf, intermediate plant height, erect flag leaf, long slender grain, and intermediate leaf senescence. In average, it can produce 7.30 t/ha grain yield but it has potentiality to give 8.71 t/ha grain yield under favorable climatic condition and appropriate agronomic management. Thousand grain weight of the variety is 21.5 gm and head rice yield is 57.2%. It is strong aromatic basmati type rice variety (according to GCMS system the value of volatile aromatic compound is 2.12 ppm), 29.2% amylose content with 8.9% protein content. Farmers can benefit financially from growing the premium quality enriched aromatic rice variety BRRI dhan104 and the total rice production will be increased along with possible to earn foreign currency by export this variety. Among the released variety by BRRI, the BRRI dhan104 is the only variety of aromatic basmati type.

First report of Sw-5 resistance-breaking strain of tomato spotted wilt orthotospovirus infecting tomato in Texas.

Tomato spotted wilt orthotospovirus (TSWV) is one of the most devastating plant viruses causing crop disease epidemics of global economic significance. A single dominant resistant gene 'Sw-5' offering a broad-spectrum resistance to multiple orthotospoviruses was introduced in tomato cultivars. However, multiple resistance-breaking strains of TSWV were reported worldwide (Ciuffo 2005; Zaccardelli et al. 2008; Batuman et al. 2017; di Rienzo et al. 2018). Symptoms suggestive of orthotospoviral infection including stunting, bronzing, and inward rolling of leaves, and concentric necrotic spots on leaves, petioles, and fruits were observed in two TSWV-resistant tomato cultivars ('BL163' and 'HT 2') planted in a tomato variety trial in Bushland, TX in 2022. Leaf tissues from 45 resistant tomato plants (symptomatic or asymptomatic) from both resistant cultivars were tested using a TaqMan probe-based qPCR assay targeting a 200bp region in nucleoprotein (N) of the TSWV (Gautam et al. 2022). While 25 of those samples tested positive for TSWV, only ten expressed characteristic disease symptoms described above. The possibility of mixed infection in those samples with other endemic viruses in the region viz., alfalfa mosaic virus, groundnut ringspot orthotospovirus, tobacco mosaic virus, tomato chlorotic spot orthotospovirus, tomato mosaic virus, tomato necrotic streak virus, tomato ringspot virus, and tomato torrado virus was discounted through RT-PCR analysis (Kumar et al. 2011; Verbeek et al. 2012; Bratsch et al. 2018). To test the RB phenotype of the observed putative TSWV-RB strains, three-week-old tomato plants from eight commercially available TSWV resistant cultivars and one non-resistant cultivar (n=10 each) were mechanically inoculated with leaf tissues collected from a single symptomatic plant from one of the field-grown resistant cultivars. The experiment was replicated twice. Hypersensitive response was observed on all inoculated leaves of resistant plants one week post inoculation. Furthermore, all eight resistant cultivars started expressing local and systemic TSW symptoms 12 to 16 days post inoculation (dpi), while non-resistant cultivar started expressing symptoms at 9 dpi. TSW incidence across all resistant cultivars was 30-70%, while in susceptible cultivar it was 90%. Symptoms exhibited by all resistant cultivars resembled those of symptoms observed in field collected plants. The expression of Sw-5 gene in all eight resistant cultivars and the lack thereof in a susceptible cultivar was confirmed using Sw-5b specific primers and using Actin as a housekeeping gene in qRT-PCR (Islam et al. 2022). The RB strains in Sw-5 resistant tomato in California (Batuman et al. 2017) had the C118Y mutation in the TSWV NSm protein, consistent with the original reporting of C118Y or T120N RB mutations in 11 TSWV isolates from Spain (NCBI accession # HM015517 & HM015518) (Lopez et al. 2011). The nucleotide and amino acid sequence analysis of NSm gene from Bushland RB isolates from four resistant cultivars (NCBI accessions # OP810513-14 [field], OQ247901-05 [mechanically inoculated]) shared 98.9 and 99.4% homology with the Californian NSm sequences of TSWV RB tomato isolate (KX898453 and ASO67371), respectively. While the Nsm C118Y or T120N RB mutations were absent in all Bushland TSWV RB isolates, they had six additional unique point mutations across the NSm (I163V, P227Q, V290I, N293S, V294I, K296Q), which could potentially be responsible for resistance breaking. Despite the lack of C118Y or T120N RB mutations, Bushland isolates were capable of disrupting Sw-5-mediated TSWV resistance in all eight commercial resistant tomato cultivars. This study suggests a new or a different class of fundamental mechanisms are likely to be responsible for resistance breaking in Sw-5b resistant tomatoes. The new RB strain/s of TSWV therefore pose a substantial threat to tomato production in TX and other tomato-growing regions of the US.

Variability of wintering oat hoodness under the influence of external environmental conditions

The article presents the results of assessment of varieties and lines of wintering oats cultivated in the soil and climatic conditions of the Republic of Adygea from the competitive variety trial nursery on the content of the husk depending on environmental factors.For comparison, agricultural years of 2017-2018 and 2021-2022 have been taken; they differ in the phase of plant development before leaving for winter and the amount of precipitation in the springsummer period. In the course of the research, generally accepted methods have been used, including «The Guidelines for the Study and Preservation of the World Collection of Barley and Oats» and GOST 10843- 76. A detailed analytical review of climatic conditions in the study period has been given, weather conditions compared with the main phases of plant growth and development, and their influence on lodging resistance and filminess of wintering oats noted. The rates of onset of heading phase and wax ripeness of grain have been analyzed, the difference in the date of their onset by years determined.As a result, data have been obtained on the husk content in oat grain per year with sufficient and excessive moisture, and the group and range of husk content variation determined. It was established that during the research period, the variability of hoodness from agrometeorological conditions was 7-8%, and from varietal characteristics 1-4%. In a year with excess moisture, the percentage of varieties with an average husk content increases, and the number with a low content of it decreases. All varieties and lines of overwintering oats have low and medium grain hoodness. Samples with low and medium content of husk, which keep this economically valuable trait stable and unchanged in years with different amounts of precipitation and are of interest for further breeding work have been selected.

Uncovering spatiotemporal pattern of floods with Sentinel-1 synthetic aperture radar in major rice-growing river basins of Tanzania

In Tanzania, 71% of rice is grown in a rainfed lowland rice production ecosystem, primarily in river basins where extreme weather events like floods are frequent. For a six-year period (2017–2022), flood mapping was conducted using Sentinel-1 data in the Google Earth Engine (GEE) platform, utilizing change detection and thresholding methodology. In addition to flood mapping, land use and land cover (LULC) were also analyzed using Sentinel-2 data in GEE, employing the Random Forest (RF) algorithm for classification. The aim was to understand the spatiotemporal extent of floods in two study locations. The resulting flood maps achieved an overall accuracy (OA) greater than 90% for all sites and study years. The findings revealed that agricultural land was the predominant land use/cover in both sub-basins, and floods were widespread in both regions. The study highlighted the interannual variability in flood extent, both spatially and temporally. Specifically, at the Ikwiriri site, floods were more extensive in 2020, covering 54.95% of the cultivated area, while in 2017, the minimum flood extent occurred, affecting 14% of the cultivated area. Similarly, at the Mngeta site, extensive floods were observed in 2020, with floods impacting 5.53% of the cultivated areas, while lower flood extents were observed in 2017, affecting 1.49% of the cultivated areas. Furthermore, the study demonstrated distinct spatiotemporal patterns of floods in both locations, with areas in proximity to rivers and wetlands experiencing more frequent floods. The research showcased the capabilities of the GEE cloud computation platform for flood inundation mapping, emphasizing its potential for enhancing our understanding of rice-producing environments. The generated flood maps can be utilized to guide the selection of areas for trials of flood-tolerant rice varieties and the dissemination of technologies such as flood-tolerant rice varieties, contributing to the resilience of rice farmers in these two floodplains.

Extending Finlay–Wilkinson regression with environmental covariates

AbstractFinlay–Wilkinson regression is a popular method for analysing genotype–environment interaction in series of plant breeding and variety trials. It involves a regression on the environmental mean, indexing the productivity of an environment, which is driven by a wide array of environmental factors. Increasingly, it is becoming feasible to characterize environments explicitly using observable environmental covariates. Hence, there is mounting interest to replace the environmental index with an explicit regression on such observable environmental covariates. This paper reviews the development of such methods. The focus is on parsimonious models that allow replacing the environmental index by regression on synthetic environmental covariates formed as linear combinations of a larger number of observable environmental covariates. Two new methods are proposed for obtaining such synthetic covariates, which may be integrated into genotype‐specific regression models, that is, criss‐cross regression and a factor‐analytic approach. The main advantage of such explicit modelling is that predictions can be made also for new environments where trials have not been conducted. A published dataset is employed to illustrate the proposed methods.

Breeding work on new potato genotypes under the conditions of Primorsky Kray

Relevance. Potato is one of the most important agricultural crops used for various purposes. Its tubers are an essential food product for many people worldwide. The development of breeding technologies and an accelerated marketing of new promising potato genotypes play a significant role in the industry of potato production today. FSBSI “FSC of Agricultural Biotechnologies of the Far East named after A.K. Chaiki” conducted a complex study on potato hybrids.The research goal was to evaluate and select promising potato hybrids with high yield, marketability, and resistance to the most dangerous diseases. The experiments were carried out in our breeding nurseries located at Putsilovka v., Ussuriysk district, in the Kazachka river valley. Hybrids Purple potato × Manifest and (Aspiya×Qusto) × Manifest were used as the research object. The methodology of FSBSI “N. I. Vavilov All-Russian Institute of Plant Genetic Resources” and FSBSI “Russian Potato Research Center” were employed for the trials of the material. Fifty-two potato varieties from different maturity groups were used as pollen sources.Results. As the result, seventy-one hybrid combinations were created, 2272 flowers were pollinated, and 640 potato fruits were obtained. The efficiency of the crossing was 28.2%. Hybrids Pri15-12-23 Purple potato × Manifest and Pri-15-15-7 (Aspiya×Qusto) × Manifest had the highest rate of potato fruit formation. These accessions were characterized by good taste and high yield (48.7-51.0 t/ha), starch content (13.9-16.3 %), and vitamin C (15.0-15.4 mg/100 g). Tubers of these genotypes were oblong-oval or round with yellow flesh and small eyes. The studied accessions showed resistance to the main plant pathogens of the Russian Far East. Currently the obtained genotypes are tested for resistance to potato wart disease (S. Endobioticum, Dahlem pathotype) in the State variety trials. These accessions generate significant interest for breeding.

Новый сорт горчицы сарептской озимой Вьюжанк

The breeders of the V.S. Pustovoit All-Russian Research Institute of Oil Crops developed artificially the winter form of brown mustard by a method of resyn-thesis first in the world in 1968–1989. The variety of winter brown mustard Suzdalskaya was a result of this work. In 2016–2021, in the V.S. Pustovoit All-Russian Research Institute of Oil Crops, the variety Vyuzhanka was developed by a method of individual selection of elite plants using self-pollination from the initial variety of winter brown mustard Dzhuna. Due to results of competitive variety trials of 2019–2021, the variety of winter brown mustard Vyuzhanka increased the standard variety Dzhuna by seeds yield on average by 0.72 t/ha. Oil content of seeds was leveled to the standard one, increase of oil yield was 0.30 t/ha. Oil produced from the seeds of the new variety Vyuzhanka is characterized with full absence of erucic acid, allyl mustard oil in seeds is within 0.60%. Winter resistance of the variety Vyuzhanka by 32% is higher than the standard one. The variety of winter brown mustard Vyuzhanka is recommended for the cultivation in all regions of the Russian Federation.

Новый скороспелый сорт подсолнечника Кремень

Kremen is a new very early maturing sunflower varie-ty of oil type. It was developed in the laboratory of Sunflower variety breeding of V.S. Pustovoit All-Russian Research Institute of Oil Crops in 2015–2021 as a result of multiple individual selection from the best families of a variety-population SUR by productivity, morphotype, tolerance to broomrape races (A–F), high field resistance to dry rot, and toler-ance to phomopsis. The new variety is differed from the standard variety VNIIMK 100 with its increased productivity (seed yield – by 14%, oil yield – by 16%) and improved morphometric traits. The period from seedling appearance to physiological maturity of 81 days is equal to the same of the standard variety. The plant height of the new variety is 145–155 cm. The weight of 1000 seeds is within 55 g at the plant popu-lation of 40 thousand seeds per ha. The sunflower variety Kremen from 2021 is under the state variety trial in the Central Chernozrn (5), Northern Caucasus (6), Middle Volga (7), Low Volga (8), Ural (9), and Western Siberian (10) regions.

Progress and prospect of developing salt and alkali tolerant rice using hybrid rice technology in China

AbstractSoil salinization and alkalization are important abiotic stresses that affect crop growth and yield. Development of salt and alkali tolerant varieties is still dominated by the following conventional breeding method: The salt and alkali tolerant traits from screened germplasm are introduced into elite varieties by means of hybridization and backcrossing. In recent years, the breeding of salt and alkali tolerant rice has also made great progress. For example, the yield of Chao‐You 1000, a two‐line rice hybrid, has reached 12.04 t/ha growing in fields with salinity between 0.2% and 0.6%. This review is an update on the progress of salt and alkali tolerant rice germplasm screening and new salt and alkali tolerant varieties in development. By reviewing the performance of current rice hybrids in China's National Regional Variety Trials of Saline‐Alkali Tolerant Rice, we proposed the technical approach of developing saline–alkali tolerant rice hybrids using the third‐generation hybrid rice technology and furthermore the trend of developing salt and alkali tolerant rice hybrids.

A non-replicated experimental design in faba bean (Vicia faba L.) variety testing – Embracing plant density variation as a strength

Plant density is one of several factors that can affect crop yield. In conventional variety trials, it is generally assumed that the plant density is optimal and similar across all varieties, but in practice, field emergence and plant density may vary among varieties. In this study, we want to investigate an alternative experimental design that may help to reduce the part of the genotype x environment interactions caused by heterogeneity in plant density among varieties. We investigate the use of a non-replicated quantitative design adapted towards regression of yield on plant density by intentionally inducing variation in plant density on the cost of repetitions, and compare it to a conventional ANOVA-focused block design. Based on two field experiments and a simulation study, we show that the estimated yield accuracy is comparable between the two designs under the condition that plant density is similar across varieties. If plant density varies, the quantitative design provides the opportunity for crop yield adjustment. Furthermore, the quantitative design allows estimation of the yield potential, the optimal plant density, and the sensitivity to low plant densities for each variety. Across experiments, varieties, and years, the yield potential was 2.18 t/ha - 7.82 t/ha, the economically optimal net yield was 2.75 t/ha - 6.62 t/ha, and the economically optimal plant density was 39.8–67.7 plants m−2. The study demonstrates that the quantitative design provides added value compared to ordinary qualitative designs, by offering additional information such as the yield potential, optimal plant density,flowering and sensitivity measures.