Highest Average Yield Research Articles

СТРЕССОУСТОЙЧИВОСТЬ СОРТОВ ЯРОВОГО ЯЧМЕНЯ ОМСКОЙ СЕЛЕКЦИИ В УСЛОВИЯХ ЗАПАДНОЙ СИБИРИ

Spring barley is a key grain-fodder and fodder crop, which forms an increased yield compared to other grain-fodder crops due to early maturity and drought resistance. Taking into account climatic factors and production demands, breeding for increased productivity and adaptability to local natural and climatic factors, resistance to biotic and abiotic stresses is relevant today. The purpose of the research was to assess the fitness of spring barley varieties (Hordeum sativum L.) bred by the Omsk Agrarian Scientific Center for the conditions of climate transition from continental to sharply continental in Western Siberia. The object of the research: eleven varieties of spring barley, which belong to the multi-row hulled (standard ‘Omskiy 99’), two-row hulled (standard ‘Omskiy 95’), multi-row hulless or “naked” (standard ‘Omskiy golozerny 2’) and two-row hulless (standard ‘Omskiy golozerny 1’). The studies were carried out in the zone of the southern forest-steppe of Western Siberia from 2011 to 2019. The coefficient of linear regression and the stability of the reaction of the yield of varieties were calculated. Under the conditions of the continental and sharply continental climate of Western Siberia, the average yield of spring barley for the period of research was 4.03 t/ha (Lim. = 2.23–5.63 t/ha). The intensive group includes varieties ‘Omskiy golozerny 4’, ‘Sibirskiy Avangard’ and ‘Sasha’ (regression coefficient more than 1). Increased stability of the yield was noted in the varieties ‘Omskiy golozerny 2’, ‘Omskiy golozerny 1’, ‘Sasha’, ‘Omskiy 90’, ‘Omskiy 96’, ‘Omskiy 100’ (stability variance less than 0.29). Varieties ‘Omskiy 96’ and ‘Omskiy 100’ are characterized by full compliance of the formed yield with those agrotechnical conditions in which they are grown at a fairly stable level of productivity formation. The highest average yield over the years of the study was formed by the varieties ‘Sasha’ (4.70 t/ha) with values of plasticity (regression coefficient is equal 1.1) and stability (stability variance is equal 0.18), ‘Omskiy 100’ (4.89 t/ha; 1.02; 0.11, respectively). We recommend them for cultivation in the region.

Spatial and operational factors behind passenger yield of U.S. nonhub primary airports

Nonhub airports are an essential component in the National Plan of Integrated Airport Systems (NPIAS) of the United States in that they connect regional towns and small communities to the air transportation network. Understanding the interplay of operational and spatial factors in determining average passenger yield of nonhub airports provides airlines with valuable information for network planning and revenue management. This study examines factors contributing to the yield variation among nonhub airports in the U.S. Using ordinary least squares (OLS) based econometric models, this study captures the spatial dependence of passenger yield of nonhub airports, which tends to increase with a corresponding increase in distance to the nearest large hub airport. Nonhub airports surrounding large hub airports with higher passenger enplanements and higher average yields also have higher yields than other nonhub airports. In addition, this study finds the effect of Allegiant Airlines in lowering the average passenger yield of the nonhub airports served directly by the airline, which can be termed as ‘Allegiant Effect’. Findings of this study could provide valuable guidance for airlines to analyze network planning strategies and to identify future markets for growth and for policymakers when allocating resources to communities relying on these nonhub airports.

Reaction norm of selection material for tests in the conditions of the Ukrainian Carpathians

The results of research on the manifestation of the reaction rate of breeding material created in the selection department of the Institute of Potato Growing and Polissya Research Department of this institute, for testing in specific soil-climatic, phytopathogenic conditions of the Ukrainian Carpathians are presented.
 According to the early accumulation of the crop, the hybrid H.09.8-14 was isolated, which was also characterized by the stability of the indicator, which cannot be noted in relation to other early forms. Among the samples of other maturity groups, the hybrid P.12.16/12 stood out, which had a higher average yield than the varieties Yavir and Chervona Ruta, by 0.01 and 0.16 t/ha, respectively. In addition, it differed in age from the standards for the manifestation of the sign.
 The hybrid H.09.8-14 was characterized by the maximum marketability of the crop, but despite its advantage over the Yavir variety in 2018 (by 0.9 %), on average it was inferior to the standard by 0.2 %. The worst conditions for the formation of the commodity harvest were in 2019, when in three samples the manifestation of the trait was less than 90 %.
 In addition to the standard varieties Yavir and Chervona Ruta, the hybrid BM.178/55 has been identified for resistance to late blight, but with specific dynamics of disease development depending on the general pathogenic situation.

Exploring the Yield Response of Paddy (<em>Oryza sativa</em> L.) under Varying Levels of Soil Nitrogen, Phosphorus and Potassium

Assessment of crop responses under varying levels of soil available nitrogen (N), phosphorus (P) and potassium (K) is important to develop site-specific nutrient management (SSNM) strategies. This study was conducted to investigate the spatial variability of soil N, P and K levels in paddy grown soils in Anuradhapura, Kurunegala and Polonnaruwa districts and corresponding yield response for nutrient application. Seventy-one paddy fields were selected and four plots (3×6 m) were established at each site comprised of a treatment applied with ample amount of N, P and K and corresponding omission treatments. At harvesting, total yield of each plot was recorded. Considerable heterogeneity of soil N (12.5-43.9 mg/kg), P (2.7-34.2 mg/kg) and K (14.6-221.9 mg/kg) was observed in paddy grown soils of the three districts. A significantly higher average yield of N applied treatment (5.8 Mg/ha) than that of N omitted treatment (3.9 Mg/ha) indicated a yield response for N application. However, nonsignificant differences of average yields of P (5.7 Mg/ha) and K (5.6 Mg/ha) omitted and ample treatments (5.8 Mg/ha) revealed a poor yield response for the application of these nutrients. Stepwise multiple regression analysis revealed that neither the initial soil P and K levels nor the other studied factors (growing season, irrigation scheme, soil texture, pH, EC, available Fe and Mg) have an impact on yield responses observed for P and K applications. Our results indicated large spatial heterogeneity in soil P and K levels in paddy grown soils. Absence of a significant response for the applied P and K and a considerable variability of yield responses highlighted the need of further studies on P and K reserves of paddy growing soils and factors controlling the variability in yield response. Further, site-specific application of N is shown as a priority to improve the productivity of paddy lands.

Ammi analysis of genotype × environment interaction and stability of sesame genotypes

The additive main effects and multiplicative interaction (AMMT) model for seed yield of 60 varieties of sesame per plant detected significant effects of the genotypes (17.87% sum of squares (SS)), environments (14.15% SS) and genotype × environment interaction (67.99% SS). The model also extracted two significant interaction principal component analysis (IPCA) with a total of 79.9% SS and 67.8% corresponding degrees of freedom. Genotype TMV-7 (17.308 g/plant) followed by N-8 (13.994 g/plant) had the highest average yield which was much greater than the grand mean (10.976 g/plant) and declared as area specific adapted genotypes. Environments El, E2 and E4 were unfavorable while E3 is the most suitable as indicated by high mean value of IPCA 1 and low value of IPCA 2.

Quality of reading among equipment for determining water content in corn kernels

Corn productivity in Brazil has been gradually increasing, and adequate storage of produce is a matter of safety; under appropriate storage, the quality of the product is preserved and losses are avoided or minimized. Hence, monitoring temperature and moisture control is essential. The objective of this study was to verify the quality of readings of equipment used to determine the water content of corn seeds according to the sowing times, and to verify the existence of correlations among the equipment. The experiment was conducted at the Research and Extension Teaching Farm (FEPE), which belongs to UNESP/FCAV in Jaboticabal, SP. The experimental design was based on the basic premise of statistical quality control (SQC). Three experimental areas were evaluated with two corn hybrids and with different days after sowing (DAS): Area A (hybrid AS1633PRO2 at 132 DAS), Area B (hybrid AS1555RR2 at 125 DAS), and Area C (hybrid AS1633PRO2 at 150 DAS). To evaluate the water content of the seeds, an expeditious method was employed using two different moisture sensors (Equipment 1 and 2) based on the principle of dielectric measurement (moisture by capacitance). The greenhouse method (Equipment 3) was also tested. The highest reading quality was observed in Equipment 1, and Area C showed less variability and a higher average yield because of the adequate physiological maturation points of the harvest and more appropriate grain water content. Equipment 3 and 1 showed better correlation between the evaluations because the calibration of Equipment 1 had readings close to those of the standard method (Equipment 3).

INFLUENCE OF BIOLOGICAL PRODUCTS AND FERTILIZERS ON THE PRODUCTIVITY OF SPRING BARLEY WITH ADDITIONAL SOWING OF PERENNIAL GRASSES

Two-factor field experiment was carried out at the research and training station of Ivanovo State Agricultural Academy in 2015-2017. The aim of the research was to establish cooperation effect of various biological products and modified mineral fertilizers on the productivity of spring barley with additional sowing of perennial grasses. As a result of the studies, it was found that the highest average yield of barley grain - 2.13 t / ha, was revealed in the conditions of timothy grass additional sowing as a sub-cover crop. At the same time, the combination of biological preparations Mizorin + Rizoagrin proved to be most effective; on average, the yield of grain and straw with this combination was 2.33 t / ha and 3.42 t / ha, respectively. When choosing meadow clover as a sub-cover crop, the maximum data on grain and barley straw yields of 2.92 t / ha and 4.26 t / ha, respectively, were obtained from the use of combination of biological products Mycorrhiza + Rizoagrin on the background of modified fertilizers. Under conditions of sowing a mixture of clover and timothy, the highest yields of grain and barley straw were 2.94 t / ha and 4.29 t / ha, respectively, obtained from the use of the biological product Rizoagrin on the background of modified fertilizers. In the course of the field experiment, positive data on additional income and profitability were obtained on most options, which were maximal in the conditions of replanting a mixture of herbs. Moreover, the largest value of the additional conditionally net income is 21.2 thousand rubles obtained from the use ofpreparation Rizoagrin on the background of modified fertilizers. And the highest profitability is 91.8 % in the absence of presowing treatment of seeds.

Oilseed Rape (Brassica Napus L.) Nutrition by Nitrogen and Phosphorus and its Effect on Yield of Seed, Oil and Higher Fatty Acids Content

The effect of phosphorus (P) and nitrogen (N) application on yield, oil and fatty acids content (especially oleic acid, linoleic acid and linolenic acid) in rapeseed was investigated in the field experiment. Also effect of weather conditions was evaluated. The polyfactorial trial was realized in experimental years 2013/2014 and 2014/2015 in terms of agricultural cooperative in Mojmírovce. The experiment was based on three variants of fertilization treatments by the block method in three replications. The size of each block was created by plots with size 600 m2. The first level of treatment 10 was non-fertilized control. The second level of treatment 2U was fertilized by nitrogen in dose 240 kg.ha-1. The third level of treatment 3P was fertilized by the same dose of nitrogen 240 kg.ha-1 and by phosphorus in dose 88 kg.ha-1. The highest average yield 3.9 t.ha-1 was achieved at treatment 3P, where phosphorus was applied. It means statistically significant yield increase by 30% compared to treatment 2U, where no phosphorus was not applied. There was statistically non-significant difference in oil content, in the range of treatments. The content of oleic acid fluctuated from 63.3% to 65.9% and the highest was reached at unfertilized control treatments in both experimental years. The linoleic acid content ranged from 20.3% to 21.2% and content of linolenic acid varied between 6.9% and 8.9%. Application of nitrogen and nitrogen + phosphorus high statistically significant decreased oleic acid content in both experimental years. Opposite effect was observed, where content of linoleic and linolenic acid was high statistically significant increased after nitrogen and nitrogen-phosphorus fertilization. Effect of unequal weather conditions and treatments of nitrogen and nitrogen-phosphorus nutrition can influence the percentage ratio of higher fatty acids composition.

Wheat genetic gains for two distinct management schemes in China: An analysis of elite spring type genotypes.

The information collected through multi-environment testing of wheat genotypes not only provides basis to identify promising genotypes but also to ascertain their yield potential and the genetic gains. For this purpose, in the presented study, the data originated from the Yunnan provincial Regional Yield Trials (RYT) conducted during 2006 and 2018 was used. During this period, 107 genotypes were evaluated at 18 locations under Upland Wheat (UW) management scheme, while 116 genotypes were evaluated at 21 locations under Field Wheat (FW) management scheme. By adopting standard statistical approaches and through repeated elimination procedures, 7 genotypes emerged as promising for UW and 11 for FW cultivation. These genotypes have genetic variance >1 and 44/33% higher average yield than that of UW/FW genotypes. Most of these promising genotypes were tested during 2016 and 2018 cropping seasons. This indicated a good genetic gain of around 0.7 t/ha in recent years from that of base year. These genotypes, however, needs to be further evaluated in diverse environments suitable for spring type wheat cultivation to ascertain the extent of their interaction with wider environmental conditions and possibility of using in local breeding programs of those target environments.

NITROUS OXIDE (N2O) EMISSION AND AGRONOMIC CHARACTER ON DIFFERENT GREEN BEAN VARIETIES (Vigna radiata L.) IN UPLAND

Cultivation activities on mug bean lands have the potential to cause N2O emissions. Efforts to reduce N2O emissions through the selection of low-emission mug bean varieties. The study was conducted at the Experimental Garden of the Agricultural Environment Research Institute, Jaken, Pati, Central Java, in July 2018 until October 2018. The experimental design used was a randomized block design with six replications and four mug bean varieties: (1), Gronong (2), Menthik (3), PB and (4), Vima 3. Parameters measured were flux and N2O emissions, plant height, number of leaves, number of branches, leaf greenery, weight of 100 seeds, yield of dry beans per tile, and yields. The results of the analysis showes that PB varieties produced N2O emission values for the lowest 1 (one) growing season of 0.17 kg ha-1season-1. Meanwhile, from the results of productivity, the Menthik variety has the highest average yield of dried seeds, which is 1.38 tons ha-1. PB varieties have a higher average weight of 100 seeds (6.28 grams 100 seeds-1). So, in mung bean varieties that produce low emissions, not necessarily have high productivity as well. Greenhouse gas mitigation strategies, especially to reduce N2O emissions can be done by selecting varieties, balanced by good soil treatment, and effective and efficient fertilization.

Dynamics, diversity and experimental precision in final irrigated rice testing: a time meta-analysis

Abstract The objective of this study was to investigate diversity, experimental conditions and dynamics of the Irrigated Rice Breeding Program of Minas Gerais - Brazil, by meta-analysis. The target traits were grain yield, plant height and days to flowering. Evaluations were based on estimates of 376 genotypes grown at three locations, in two final comparative trials, in 14 growing seasons. Stability of the overall averages of the traits plant height and days to flowering was observed, indicating an adequate plant height and medium cycle. High average yields (>5,000 kg ha-1), good experimental accuracy and genetic variability were recorded. However, the genetic variability of all traits decreased over time, indicating the need to increase genotypic diversity. The parameter estimates of the morphoagronomic traits studied in time meta-analysis indicated the dynamic nature and good accuracy of the Irrigated Rice Breeding Program of Minas Gerais.

Using the genetic diversity of the Malus genus to solve the priority areas of breeding

The breeding use of the most valuable species and interspecies forms of fruit plants remains currently the most important biological resource for creating the varieties with increased adaptability to the complex of abioand biotic stressors of the environment, improved biochemical composition of fruits and with other important features for breeding. The results of a long-term study (2005-2019) of interspecific hybrid forms of apple-tree-representatives of the Malus genus, growing in the North Caucasus Region of Russia are presented. The aim of the study is to identify the most rapid and productive interspecific hybrid forms of apple-tree with polygenic and oligogenic types of scab resistance (Venturia inaequalis (Cook) G. Winter). Modern breeding programs and methods were used. We have identified the early-fruiting interspecies apple forms created with the participation of the summer Melba variety, the species of M. purpurea. It is allocated the elite and selected apple forms resistant to scab with a high average yield (29.03-40.03 t/ha), high indicators of total yield (377.27-520.33 t/he) from hybrid families with the participation of species: M. atrosanguinea 804/240-57, M. floribunda 821, M. purpurea and the large-fruited form No. 62 (created with the participation of Golden Delicious 4x, Wolf River, M. atrosanguinea 804/240-57) with fruits of 202.3 g an average weight.

Analysis of Climatic Potential Productivity and Wheat Production in Different Producing Areas of the Northern Hemisphere

Cultivation patterns under water saving management are closely related to climate change and crop productivity. Survey data for wheat production in China, Canada, and the USA from 1965 to 2014 was analyzed through classification statistics, comparative analysis and weighting methods. The results showed that China, Canada and the USA wheat grain production accounts for 26.49% to 34.68% of global wheat production. Of these three countries, both the highest total yield and the highest average yield per area sown were in China post 1985. Since 2000, China has accounted for 10.70% to 11.12% of global wheat planted area, producing 15.73% to 17.45% of global wheat output. Achieving high wheat yield in China was mainly based on consuming more irrigation water. The per capita arable land in China, Canada and the USA was 0.10 ha, 1.31 ha and 0.70 ha, respectively. The per capita arable land in Hebei, China, Saskatchewan, Canada and Oklahoma, USA was 0.09 ha, 16.11 ha and 3.48 ha, respectively. Hengshui, China (HS) produces two crops a year. Outlook, Saskatchewan, Canada (OK) and Woodward, Oklahoma, USA (WW) produce one crop a year. Mean precipitation averages 109 mm, 210 mm and 291mm during the wheat growing season, respectively. Due to less per capita arable land in China, achieving high yield means higher water consumption, which creates a sharp contradiction between water scarcity and demand for grain in China. Consequently, high water use efficiency technologies in agriculture are more needed in China than in the other two countries. High demand for water at post 1985 yield levels cannot be met by rain-fed production in HS. Grain yields of 5975.6 kg/ha to 7031.2 kg/ha can be achieved with irrigation. Economic benefits mainly determine wheat production in the USA and Canada, whereas in China production is driven by food security and sustainable production goals. The conclusions of this paper could provide a reference for wheat production in different regions.

MoP supported on reduced graphene oxide for high performance electrochemical nitrogen reduction.

Electrocatalytic nitrogen fixation under ambient temperature and pressure has always been considered crucial in the ammonia industry. In this study, MoP nanoparticles were evenly grown on few-layered reduced graphene oxide (MoP@rGO) and served as an efficient electrocatalyst for NRR. The MoP@rGO electrocatalyst showed an excellent NRR activity with a high average NH3 yield of 7.5 μg h-1 mg-1cat (at -0.6 V vs. RHE) and high faradaic efficiency of 9.1% (at -0.5 V vs. RHE). The excellent catalytic activity and stability of MoP@rGO originated from the increased rate of electron transfer between MoP and rGO, enlarged active surface area, synergetic effect between MoP and rGO, and excellent chemical stability. This study thus opens an alternative route towards NRR electrocatalysis.

The influence of microbial inoculums on yield and yield components of rocket (Eruca sativa Mill.)

The use of microbial inoculums can improve growth and yield of plants without use of agrochemicals which can result in obtaining quality food. Rocket is widely grown for spice and salad in the areas of Mediterranean Sea. Having in mind the importance of rocket in human diet the research was carried out in rocket grown in unheated protected houses. The experiment included four variants as follows: variant 1 control – untreated variant; variant 2 – treated with application of inoculum from the product Uniker into the soil before the sowing of the rocket; variant 3 – treated with application of inoculum from two different products Uniker and Slavol S before sowing of the seeds, whereby Slavol S was applied by immersion of the seeds for five minutes before sowing, and Uniker was applied in the soil before the sowing of the rocket; variant 4 – treated with foliar application of live cells of bacteria Azotobacter sp. (10-6 cfu/ml) every fifteen days during vegetation. During the vegetation total yield (t/ha) and yield components were measured. The results showed that the highest average yield (22,30 t / ha) was achieved by variant 4. Also the highest average value for the weight of the whole plant (4,22 g), root weight (0,50 g), rosette weight (3,73 g) and leaves weight (2,50 g) was obtained by variant 4. The highest average value for the number of leaves was measured in variant 3 (6,13) while the root length was highest in control variant (116,70 mm).

Towards Sustainable Oil Palm Plantation Management: Effects of Plantation Age and Soil Parent Material

This study was conducted to generate information required to guide plantation management in relation to replanting on soils derived from different parent materials. Six oil palm estates in coastal lowlands of southwest Cameroon were considered. Oil palm yield data (in t⋅ha−1 of fresh fruit bunch, FFB) and corresponding age of palms (in years after planting, YAP) were obtained for the various estates. In all the estates, average yields were ⋅FFB⋅ha−1 and highly variable. Plantation age, solely, explained between 20% - 58% of the variation in yield. The highest average yields (11.5 t⋅FFB⋅ha−1) were obtained in plantations aged between 9 and 18 YAP and the lowest (4.66 t⋅FFB⋅ha−1) were obtained in old plantations (>23 YAP). Plantations located on volcanic parent materials generally had higher yields compared to those established on sedimentary parent materials. In order to intensify production and increase yields while conserving the environment, one important measure to consider is the replacement of aged palms, and the recommended optimal replanting age in coastal plains of southwest Cameroon should be at most 23 YAP. Estimated mean yields, if aged palms are replanted on time, can increase by 43% - 65%. Additionally, site-specific nutrient management options should be considered in plantation intensification programs.

Relative efficacy of synthetic insecticides against sucking insect pests of chilli crop

The experiment was conducted to evaluate relative efficacy of synthetic insecticides against sucking insect pests of chilli crop at Bozdar Agriculture Farm, Distrcict Tando Allahayar during-2015. The chilli variety Advanta-509 was sown and treated with insecticides T1= Deligate (Spinetoram) 25 water dispersible granule (WG) 4 mg/1lit water, T2= Novastar (Bifenthrin + Abamectin) 11.5 emulsifiable concentrate (EC) 5ml/1lit. Water and T3 = Transfarmer (Sulfoxaflor) 50 WG 3 mg /1 lit water of water at 1 DAS, 4 DAS, 7 DAS and 10 DAS (Days after Spray) intervals in each treatment. The results indicated that spinetoram and bifenthrin + abamectin insecticides was found best for reduction in thrip per leaf and flower population as compare to sulfoxaflor insecticides. The result further revealed that a bifenthrin + abamectine insecticide was found more excellent for whiteflies reduction in population followed by spinetoram and sulfoxaflor insecticides. Similarly, a sulfoxaflor insecticide was declared more excellent for management of aphid in chilli crop followed by bifenthrin + abamectin and spinetoram insecticides. The highest average yield was obtained plot treated with insecticide sulfoxaflor followed by insecticides Bifenthrin + Abamectine, spinetoram and control (Untreated), respectively. The analysis of variance of results indicated that there is no significant (P<0.05) difference in yield obtained from plot treated with insecticide, however, the control (untreated) plot significantly (P<0.05) different than insecicide. Keywords: Abamectine; Bifenthrin; Chilli; Suking Insects; spinetoram; sulfoxaflor http://dx.doi.org/10.19045/bspab.2019.80170

Hybrid-electric system truth test: Energy analysis of Toyota Prius IV in real urban drive conditions

The experimental work, carried out through road tests in the city of Rome (Italy), assesses the energy performance of the Toyota Prius IV generation with Full Hybrid traction system under real conditions of use in the urban environment.The evaluation was carried out through a data collection campaign on a 37 km urban route, in both fast-flowing sections and traffic-congested areas of Rome. On this route, 60 driving tests were carried out by individual with different characteristics in terms of gender, age and hybrid technology driving experience.In particular, the analysis involved the operation as ZEV (Zero Emission Vehicle) vehicle, the hybrid system Power flows, fuel consumption and yields.The most relevant results relate to the high percentage (in time and space) of operation in ZEV mode: this mode is achieved both in “electric” operation, that is, with power output to the wheels by the electric motor only (with the ICE off), and in the inertial operation, i.e. without power output to the wheels (always with ICE off).Another important result concerns the high overall efficiency of the hybrid traction system, obtained thanks to the high average yield of the ICE, and especially through the very high deceleration energy recovery. The recovered energy provides a very significant contribution to the total energy needed by the wheels for the car movement purposes and, in particular, provides the vast majority of electricity required by the electric motor.

Evaluation of early maturing promiscuous soybean varieties in the irrigated and the rain-fed areas of Sudan

Soybean (Glycine max (L.) Merr.) is relatively a new crop in Sudan. Limited number of improved varieties for commercial use requires the development of early maturing and high-yielding soybean varieties suiting the diverse agro-climatic zones of the country. Eight promising soybean varieties introduced from the International Institute of Tropical Agriculture (IITA) were evaluated at eight irrigated and rain fed environments at Wad Medani, Kenana, and Damazin from 2014 to 2016. The improved late maturing varieties Sudan1 and Sudan2 were used as checks. Trials were arranged in a randomized complete block design with four replicates. The highest grain yields were obtained for the checks Sudan1 (2400 kg ha−1) and Sudan2 (2330 kg ha−1); followed by the introduced varieties TGx 1972-11F (2160 kg ha−1) and TGx 1977-2F (2040 kg ha−1). However, TGx 1987-10F and TGx 1972-11F were earlier than the checks, at least 2-week differences in the 50% flowering and days to maturity. Comparing these two varieties with the checks, TGx 1972-11F and TGx 1977-2F had 1.00 and 0.99, 95% confidence interval, indicating that these two varieties had a good yield stability over environments. Grain yield was also positively correlated with fodder yield, plant height, pods plant−1, and harvest index. The high average grain yields and yield stability of TGx 1972-11F across environments, coupled with its early maturity and good grain quality, makes the TGx 1972-11F an excellent choice to be released for commercial use. This prompted the National Variety Release Committee of the country to release it under the name of “Soya4.”

SCREENING OF THE CUCUMBER COLLECTION FOR RESISTANCE TO DOWNY MILDEW IN THE LOWER VOLGA REGION

Background. Currently, the most widespread and harmful disease of cucumber is downy mildew. In this regard, a vitally important trend in cucumber breeding is the development of new cultivars, more resistant to downy mildew, for cultivation in different regions. Solution to this problem requires searching for donors of resistance for use in breeding practice.Materials and methods. The studies were conducted at Volgograd Experiment Station of VIR using conventional methods. The material for the screening was the collection of cucumber genetic resources held by VIR.Results and conclusions. During 32 years of work, 2873 cucumber accessions from VIR’s holdings were screened. As a result, 57 accessions with resistance or relative resistance to downy mildew were identified, i. e. 2.0% of the total number studied. Immune accessions were not found. Among the selected accessions, those with the highest yield are noteworthy: landraces from Azerbaijan (temp. k-3999 and temp. k-4004) as well as the cultivars from China ‘Zungsungerum-oi’ (temp. k-3701), ‘Tianin mini cucumber’ (k-4490), ‘Tian Uzin Yao No. 5’ (temp. k-3840) and ‘Tian Uzin Yang No. 6’ (temp. k-3841). Of the resistant and relatively resistant accessions, 76% were from Southeast Asia. During the years of study, 23 accessions, previously resistant to downy mildew, lost their resistance and suffered severe damage from the disease. Hence, it seems obvious that resistant accessions should be periodically retested for susceptibility to downy mildew. Twenty accessions were selected to form a group of tolerant ones. Of these, ‘Yeo leam sam chuk oi’ (k-4545), ‘Crispy Top F1’ (temp. k-3549) and ‘Pchelka F1’ (temp. k-3981) had the highest average yield.