Heterotic Hybrids Research Articles

Principal component analysis for yield attributing traits of sunflower (Helianthus annuus L.) genotypes

In order to evolve the potential heterotic hybrids in sunflower, efforts are on in plant breeding programmes toselect promising parental inbreds for various yield related traits. Ninety one sunflower germplasm accessions were evaluated for seven quantitative traits during rabi2018-19 and data were subjected to biometric analysis for correlation and principal component analysis. PCA analysis revealed that, out of 7 PCs, only 3 PCs exhibited more than 1.0 Eigen value and showed 71.45% variability for 91 genotypes. PC1 reported for highest variability in traits like days to 50% flowering and days to maturity. PC3 showed the positive load on yield attributing traits like 100 seed weight and single plant yield. PC1 and PC3 allowed for simultaneous selection of yield related traits.

Development of heterotic hybrid in bitter gourd (Momordica charantia L.) for earliness and high fruit yield

The present investigation was undertaken to study the magnitude of heterosis in 45 hybrids (F1s) developed by following the Line × Tester mating design using fifteen lines and three testers for earliness and high fruit yield. Among the parents, OBGCBR-2 and IC-085611 have performed as superior genotypes for heterosis. Highest degree of heterosis for most of the traits i.e., earliness and fruit yield traits were registered in desired direction in the hybrid OBGCBR-2 × Jaunpuri Green. Estimation of standard heterosis in cross OBGCBR-1 × IC-085611 recorded desired relative heterosis for days to 50% pistillate flowering. Heterosis for node at which 1st pistillate flower appears was in the desired direction in cross OBGCBR-2 × Jaunpuri Green for standard check and; hybrid Meghna × Jaunpuri Green for relative heterosis and heterobeltiosis. Hybrids Katehi × IC-085612 exhibited negative and significant relative heterosis and heterobeltiosis for internodal length. In case of sex ratio and fruit length cross OBGCV-2 × IC-085612 showed heterosis in desired direction for relative parent and heterobeltiosis. The positive and significant, relative parent and heterobeltiosis was in the hybrid Green Jhalari × Jaunpuri Green for fruit diameter. For average fruit weight positive and significant heterosis observed in cross OBGCBR-2 × IC-085611 over standard parent. Estimation of standard heterosis for number of fruit plant-1 indicated that the hybrids OBGCBR-2 × IC-085611 found to be desirable superior cross combinations over standard heterosis followed by Meghna × Jaunpuri Green for relative parent and heterobeltiosis.

Gibberellins and Heterosis in Crops and Trees: An Integrative Review and Preliminary Study with Brassica.

Heterosis, or hybrid vigor, has contributed substantially to genetic improvements in crops and trees and its physiological basis involves multiple processes. Four associations with the phytohormone gibberellin (GA) indicate its involvement in the regulation of heterosis for shoot growth in maize, sorghum, wheat, rice, tomato and poplar. (1) Inbreds somewhat resemble GA-deficient dwarfs and are often highly responsive to exogenous GA3. (2) Levels of endogenous GAs, including the bioeffector GA1, its precursors GA19 and GA20, and/or its metabolite GA8, are higher in some fast-growing hybrids than parental genotypes. (3) Oxidative metabolism of applied [3H]GAs is more rapid in vigorous hybrids than inbreds, and (4) heterotic hybrids have displayed increased expression of GA biosynthetic genes including GA 20-oxidase and GA 3-oxidase. We further investigated Brassica rapa, an oilseed rape, by comparing two inbreds (AO533 and AO539) and their F1 hybrid. Seedling emergence was faster in the hybrid and potence ratios indicated dominance for increased leaf number, area and mass, and stem mass. Overdominance (heterosis) was displayed for root mass, leading to slight heterosis for total plant mass. Stem contents of GA19,20,1 were similar across the Brassica genotypes and increased prior to bolting; elongation was correlated with endogenous GA but heterosis for shoot growth was modest. The collective studies support a physiological role for GAs in the regulation of heterosis for shoot growth in crops and trees, and the Brassica study encourages further investigation of heterosis for root growth.

Identification of heterotic groups in South-Asian-bred hybrid parents of pearl millet.

Pearl millet breeding programs can use this heterotic group information on seed and restorer parents to generate new series of pearl millet hybrids having higher yields than the existing hybrids. Five hundred and eighty hybrid parents, 320 R- and 260 B-lines, derived from 6 pearl millet breeding programs in India, genotyped following RAD-GBS (about 0.9 million SNPs) clustered into 12 R- and 7 B-line groups. With few exceptions, hybrid parents of all thebreeding programs were found distributed across all the marker-based groups suggesting good diversityin these programs. Three hundred and twenty hybrids generated using 37 (22 R and 15 B) representative parents, evaluated for grain yield at four locations in India, showed significant differences in yield, heterosis, and combining ability. Across all the hybrids, mean mid- and better-parent heterosis for grain yield was 84.0% and 60.5%, respectively. Groups G12 B × G12 R and G10 B × G12 R had highest heterosis of about 10% over best check hybrid Pioneer 86M86. The parents involved in heterotic hybrids were mainly from the groups G4R, G10B, G12B, G12R, and G13B. Based on the heterotic performance and combining ability of groups, 2 B-line (HGB-1 and HGB-2) and 2 R-line (HGR-1 and HGR-2) heterotic groups were identified. Hybrids from HGB-1 × HGR-1 and HGB-2 × HGR-1 showed grain yield heterosis of 10.6 and 9.3%, respectively, over best hybrid check. Results indicated that parental groups can be formed first by molecular markers, which may not predict the best hybrid combination, but it can reveal a practical value of assigning existing and new hybrid pearl millet parental lines into heterotic groups to develop high-yielding hybrids from the different heterotic groups.

Combining Ability and Heterosis of Sorghum (<i>Sorghum bicolor</i> L. Moench) Hybrids for Grain and Biomass Yield

This study was carried out to estimate the magnitude of heterosis and combining abilities (general & specific) for forage and over all grain yield performance of sorghum hybrids. Even though, information on heterotic performance and combining ability of Ethiopian elite sorghum lines for biomass, yield, and overall performance is too insufficient, there is ample amount of sorghum elite lines developed through pedigree breeding. The result of ANOVA found out that mean squares had to indicate a considerable amount of variability among the tested genotypes for most traits. Parents and hybrids are drastically unique for all traits besides thousand-grain weight, number of green leaves, and panicle width. This found out that hybrids have a higher yield than Open pollinated types (OPVs) parents. Hybrids, 106 × 94 (123.5%), 106 × 87 (80.4%), 106 × 78 (72.5%), 107 × 92 (74.5%) 107 × 99 (56.9%), and 107 × 104 (60.8%) have been discovered maximum heterotic hybrids for yield in comparison to check. The estimations of parental GCA effects confirmed that female 106 and males 79, 96, 94, and 81 had been excellent general combiners for biomass, yield and associated traits. Primarily based on perse overall performance, heterotic response, and combining ability, female parent 106 and male parents 94, 102, and 90 were observed maximum performed. Those parental lines could be used for hybrid and germplasm improvement.

Combining ability and heterosis for grain minerals, grain weight and yield in pearl millet and SSR markers based diversity of lines and testers

Pearl millet, a versatile and historic coarse grain crop, is stable food for millions of people in India and sub-Saharan Africa. As part of a key initiative to increase its grain mineral content, an investigation was carried out with line × tester analysis to generate information on magnitude of heterobeltiosis and standard heterosis, gene effects, combining ability effect of parents and hybrids for grain yield, grain weight and grain minerals (iron, zinc, copper and manganese). The partitioning of variance due to parental genotypes revealed that lines and testers significantly differed for studied traits. The per se performance of hybrids was higher than parents in desired directions for most of the characters suggesting the possibility of heterotic hybrids. The potence ratio was less than 1 for all traits except Fe. The analysis of variance for combining ability revealed importance of both additive and non-additive components of genetic variance. On the basis of per se performance and combining ability analysis cross ICMA 98444 × AIB 220 may be directly exposed for commercial cultivation and may be advanced for development of parental genotypes. During SSR marker based study, maximum PIC value was revealed by Xpsmp 2203 (PIC value = 0.92). Clustering analysis could group parental genotypes in three main clusters. The genetic distance among 15 genotypes ranged from 0.29 to 0.83. The genetic relationships identified among the male sterile/restorer lines may be useful in designing strategies to improve the genetic variation in the context of pearl millet breeding and to develop heterotic crosses.

Assessing the performance of hybrids developed using iso-cytoplasmic restorers and identification of promising combiners in rice

Iso-cytoplasmic restorers (ICRs) are valuable source of fertility restoration for three linerice hybrids derived from wild- abortive cytosterile (WA-CMS) lines. They carry a full complement of fertility restorer (Rf) genes and sterile cytoplasm. We have test-crossed a set of 25 ICRs with four WA-CMS lines namely, IR 79156A, IR 58025A, Pusa 6A and RTN 12A following a line x tester mating design. Significant estimates of general and specific combining ability for agro-morphological traits revealed the involvement of both additive and non-additive gene effects. The combining ability estimates implied that some of the restorers were good general combiners for traits such as plant height, number of tillers per plant, panicle length,spikelet fertility, grain weight and yield per plant. Four promising ICRs namely, PRR317, PRR354, PRR381 and PRR390 with high general combining ability for yield across different environments were identified based on theirhybrid performance. Additionally, location-specific ICRs, namely PRR300 and PRR396 for timely sown conditions of New Delhi, PRR348 for Pusa and Karnal, and Pusa 307 for Karnal and late sown conditions of New Delhi environments were identified. The restorer turnover in the current study demonstrates ICRs as potential source for restorer development and can lead to the development of heterotic hybrids.

High-throughput identification of SNPs reveals extensive heterosis with intra-group hybridization and genetic characteristics in a large rapeseed (Brassica napus L.) panel

Genetically diverse germplasm sets are necessary for the identification of heterotic groups in hybrid breeding programs. Assigning parental lines to identified heterotic groups may increase the efficiency of hybrid rapeseed breeding programs. In this study, the genetic diversity, population structure, relationship, and linkage disequilibrium (LD) of 995 rapeseed accessions, including improved breeding lines and parental lines of elite hybrids, were analyzed using a 60K single nucleotide polymorphism array. The whole population was divided into four subgroups according to the parameters of principal component analysis and STRUCTURE. The overall LD decay was fast, and the LD of the A genome decayed faster than that of the C genome. A core set containing 35 accessions was selected using the POWER-CORE program. The heterotic groups were first assessed based on SNPs in the enlarged core set containing core set accessions and parental lines of three elite hybrid. The parental lines were assigned to certain subpopulation (Pop2 in the enlarged core set), in which the accessions are almost the semi-winter or winter OSR lines. The results revealed that the likelihood of developing heterotic hybrids is much higher with intra-group parents. The studies about information regarding the levels of population structure of core sets combined with their ecological adaptability and genetic distance may be useful for the efficient selection of ideal parental lines during rapeseed hybrid breeding program.

Evaluation of genetic diversity of parental lines for development of heterotic groups in hybrid rice (Oryza sativa L.)

Knowledge of genetic diversity and potential heterotic relationships among parental lines is of significant importance in hybrid rice breeding programs. In the present study, in order to understand the genetic diversity among 96 parental lines, they were characterized for their diversity with respect to their morphological traits (n = 12) and molecular markers using a set of 50 SSR markers. Morphological diversity was estimated using Mahalanobis D2 statistics in terms of generalized group distance. Based on morphological diversity analysis, the 96 lines were grouped into 5 major and 13 monogenotypic clusters. In molecular marker analysis, the parental lines were consistently clustered into B (Maintainer group) and R (Restorer group) groups based on distance and model based approaches. Strong correspondence was observed between the pedigree of parental lines with molecular genotyping based grouping than morphological trait based grouping. From the results of the present investigation, it is evident that the available diversity among the two groups i.e., maintainer group (B) and restorer group (R) is sufficient for developing heterotic hybrids, but within the maintainer and restorer groups, the diversity is limited, the diversity among restorers was moderate, while it was low among the maintainers and hence efforts are needed for broadening their genetic base of parental lines for development and adoption of high-yielding hybrids.

Productivity of sugar beet sterility maintainers on selective agricultural backgrounds with regulated abiotic factors

Aim. To determine the variability productivity components of the sterility maintainers against the selective agricultural background; to differentiate the lines according to the environmental parameters of plasticity and stability; to select the best lines for obtaining highly adaptive heterotic hybrids. Methods. Breeding material testing against agricultural backgrounds with different combinations of controlled abiotic factors and the method of Eberhard-Russell. Results. The average yield increased by 0.4 t/ha on LGS+NNB and by 1.1 t/ha on LGS+RNB. LGS+RNB reduced sugar content in roots. The highest sugar content values were recorded in O-type 1 line on LGS+NNB (18.6%) and in the O-type 2 line on NGS+NNB (19.4%). O-type lines were differentiated according to the response to the change of abiotic factors. Conclusions. O-type lines are characterized by a specific response to the controlled abiotic factors. O-type 4 and O-type 6 lines can be attributed to intensive type. O-type 3 and O-type 5 lines are considered stable for both signs. O-type 1 and O-type 2 lines showed relative stability by yield and an intensive response to the variability of the medium by sugar content. Keywords: sterility maintainers, yield, sugar content, genotype effect, the coefficient of plasticity.

Estimation of heterosis for yield and yield attributing traits in tomato crossed with line and tester method

This study was conducted to estimate heterosis for the yield and yield contributing traits of 32 cross combinations involving 12 diverse lines of some Bangladeshi tomato genotypes considering line x tester mating fashion at the experimental field of Sher-e-Bangla Agricultural University, Dhaka in 2016-2017 and 2017-2018 winter season. The experiment was designed in a Randomized Complete Block Design (RCBD) with three replications. The analysis of variance (ANOVA) showed highly significant difference for all the characters suggesting the presence of genetic variability among the studied materials. Four cross combinations (L1xT1, L3xT2, L3xT3, L5xT1) showed desirable negative significant heterosis for days to first flowering in both relative heterosis (RH) and heterobeltiosis (HB) ranged from -2.56% to -19.05%, respectively. Highest positive significant heterosis in both RH and HB was observed in four crosses L4xT4 (63.48% and 48.25%), L5xT2 (46.77% and 46.27%), L5xT4 (62.58% and 34.78%) and L8xT3 (37.39% and 35.12%) for individual fruit weight (g), while six crosses L1xT2, L1xT4, L3xT2, L4xT4, L5xT4 and L6xT1 exhibited highest positive significant heterosis for yield per plant (kg) in both HB and RH ranged from 16.09% to 88.46% respectively. Heterotic hybrids with maximum number of studied desirable yield contributing traits (8) of both RH and HB were identified only two crosses L1xT2 and L4xT4.
 Progressive Agriculture 30 (2): 179-185, 2019

Characterization of Mimban maize landrace from North-Eastern Himalayan region using microsatellite markers

The North-Eastern Himalayan (NEH) region of India is endowed with rich maize genetic resources which is important from both genetics and evolutionary viewpoints. Mimban landrace of maize is a popular choice in Mizoram as food among the locals due to its stickiness caused by recessive wx1 gene resulting in high amylopectin in the grains. In the present study, a set of 24 Mimban accessions possessing high amylopectin (mean 89.72%, range 80.2–93.7%) content were analyzed. 93 SSRs markers generated a total of 334 alleles with a range of 2–9 and mean of 3.59 alleles per locus. Polymorphism information content varied from 0.117 to 0.829 with an average of 0.528. A total of 20 unique and 24 rare alleles were detected. Twenty-seven major alleles with individual frequencies exceeding 0.70 were also identified across the accessions. Cluster analyses classified 24 genotypes into three major clusters each having 2, 14 and 9 accessions. The clustering pattern was largely congruent with the geographical information. Diverse origin of the accessions was also depicted by the SSR based principal coordinate analysis. These accessions with high amylopectin content from diverse clusters may be crossed to derive heterotic hybrid and also might be used for novel gene identification. Thus information generated here possesses great potential in their utilization in the waxy corn genomics and breeding and emphasizes the need for further exploration of unique trait specific genepool from unexplored areas. This is the first report of molecular characterization of Mimban landrace accessions from NEH region.

Introduction pages

Notulae Botanicae Horti Agrobotanici Cluj-Napoca (NBHA), Issue 3, Volume 47, 2019: The papers published in this issue Vol 47 No 3 (2019) represent new exciting researches in different topics of life science, respectively in plant science, horticulture, agronomy and crop science. Among the interesting articles we invite you to find news about the ecology, cultivation and utilization of the aromatic Greek oregano (Origanum vulgare L.); phytochemical and antioxidant properties of fresh fruits and some traditional products of wild grown raspberry (Rubus idaeus L.); biochemical characterisation and sensory evaluation of differently coloured and shaped tomato cultivars; tyrosinase inhibitory and antioxidant activity of wild Prunus spinosa L. fruit extracts as natural source of bioactive compounds; cross compatibility analysis to identify suitable parents of Tagetes erecta and T. patula for heterotic hybrid breeding; genetic diversity and population structure analysis of sand pear (Pyrus pyrifolia) ‘Nakai’ varieties using SSR and AFLP markers. Notulae Botanicae Horti Agrobotanici Cluj-Napoca journal has moved to online-only publication at the start of 2017; beginning in 2019, the journal appears quarterly. At the same time, we maintain our standard publication, as printed form, with ‘classic’ style - volume, issue, pagination.

Identification of differentially expressed transcripts at critical developmental stages in sorghum [Sorghum bicolor (L.) Moench] in relation to grain yield heterosis.

Evaluation of a set of 10 F1 hybrids along with their female (27A and 7A) and male parents (C 43, RS 673, RS 627, CB 26, and CB 29) for grain yield and its component traits revealed that grain yield/plant followed by panicle weight, primary branches/panicle, and 100-seed weight exhibited high levels of heterosis. Eight hybrids exhibited 50% or more mid-parent heterosis for grain yield/plant, of which, one hybrid (27A × RS673) recorded heterobeltiosis above 50% (73.61%). Differential display analysis generated about 2995 reproducible transcripts, which were categorized as UPF1-expressed in any one of the parents and F1 (10.53-14.76%), BPnF1-expressed in both parents but not in F1 (4.56-11.44%), UPnF1-expressed in either of the parents and not in F1 (17.95-27.40%), F1nBP-expressed only in F1 but not in either of the parents (14.39-20.54%), and UET-expressed in both parents and F1 (34.52-42.43%). A comparison between high and low heterotic hybrids revealed that the proportions of UPF1 and F1nBP transcript patterns were much higher in the former (21.31% and 45.24%) as compared to the latter (16.67% and 32.14%) at the booting and flowering stage, respectively, indicating the role of over-dominance and dominance in the manifestation of grain yield heterosis. Significant positive correlations were observed for differential transcript patterns with mid-parent and better-parent heterosis for the components of grain yield such as primary branches (0.63 and 0.61 at p < 0.01) and 100-seed weight (0.64 and 0.52 at p < 0.01). Cloning and sequence analysis of 16 transcripts that were differentially expressed in hybrids and their parental lines revealed that they code for genes involved in basic cellular processes, cellulose biosynthesis, and assimilate partitioning between various organs and allocation between various pathways, pyrimidine, and polyamine biosynthesis, enhancing ATP production and regulation of plant growth and development.

DEVELOPMENT AND ECONOMIC-BIOLOGICAL CHARACTERISTICS SORGHUM-SUDAN HYBRIDS

Due to a high stooling coefficient and good growing after cutting, sorghum can be used in the green conveyor in the summer between the cutting of annual and perennial grasses, in the fall when the growth of perennial grasses stops. Hybridization of Sudan grass with CMS-lines of various sorghum types (grain and sweet), produces highly heterotic sorghum-Sudan hybrids which exceed the parental forms in green mass productivity by 1.5 times or more. The identification of new sorghum-Sudan hybrids with high heterotic effects on productivity of green mass and dry matter with their future introduction into production is an important direction of sorghum breeding. The purpose of this work is to identify the main stages of the development of sorghum-Sudanese hybrids and to estimate indicators of their productivity and quality. The CMS lines of grain and sweet sorghum, highly productive varieties of Sudanese grass and new sorghum-Sudan hybrids are the objects of the study. The initial stage is the selection of parental forms. Highly productive and permanent varieties are of great necessity as pollinators. In our studies, these are the varieties “Svetloplenchataya 1”, “Chernoplenchataya 11” and “Chernoplenchataya 10” with 33–42 t/ha of green mass for 2 cuttings. Due to the more powerful plant development the new sorghum-Sudanese hybrids produce 52–77 t/ha of green mass for 2 cuttings. Genuine heterosis is 22.6–102.6%. During the study there have been identified the hybrids “APV-1115 x Svetloplenchataya 1” and “Zersta 38 x Chernoplenchataya 11”, that combine the maximum values of the productivity of green mass and dry matter.

Cross Compatibility Analysis to Identify Suitable Parents of Tagetes erecta and T. patula for Heterotic Hybrid Breeding

Seven interspecific crosses of Tagetes erecta × T. patula were conducted in this study. The cross compatibility index, seed setting rate, germination rate, phenotype, ploidy level, heterosis over male parent and field performance were tested. The results showed that different cross compatibility indices of Tagetes vary greatly, from 10.44~114.41, which is far less than that of the intraspecific hybridization S-121 × I-506 index. The seed setting rate of each cross ranged from 15.67% to 49.0%, and the cross S-121 × TP-512 scored the highest seed setting rate, which was higher than that of the intraspecific cross S-121 × I-506 (35.85%). Compared with the male parent, F1 has higher plant height, wider crown width, larger flower diameter and more ray florets and earlier bloom with two exceptions. The S-121 of T. erecta was diploid. All of the male parents of T. patula were tetraploids, and the combinations were triploids. The traits of plant height, plant width, flower size and number of ray florets showed positive heterosis over the male parents, and the days leading to flowering showed both positive and negative ones. Finally, S-121 × TP-379 and S-121 × TP-512 were selected as the two best combinations. This study confirmed that the two species of marigold could be crossed for better F1 varieties with improved performance.&#x0D; &#x0D; *********&#x0D; In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.&#x0D; *********

Frequency of heterotic hybrids in relation to parental genetic divergence and general combining ability in blackgram [Vigna mungo (L.) Hepper

An investigation was carried out to test the predictability of frequency of heterotic hybrids based on parental gca effects and genetic diversity in blackgram. The 40 F1s effected using 10 lines and 4 testers were evaluated along with their parents for 10 productivity per set raits. The overall gca status (high and low) of each parent and overall sca and heterotic status (high and low) of each hybrid across 10 traits were determined. Based on overall gca status and genetic divergence of parents, the hybrids were grouped into different classes. The hybrids involving parents contrasting for overall gca status and/or those involving parents with intermediate genetic divergence were more frequently heterotic than those involving comparable gca status and with extreme genetic divergence. It is hence, desirable to involve parents with intermediate genetic divergence and contrasting gca effects to recover higher frequencies of heterotic hybrids for productivity per se traits in blackgram.

Studies on genetic diversity in brinjal (Solanum melongena L.)

Genetic divergence among fifty six brinjal (Solanum melongena L.) genotypes was investigated based on twelve agronomic traits. Significant variations were observed among the brinjal genotypes for all the traits studied. D2 analysis resolved fifty six genotypes into as many as eight clusters. Maximum genotypes were gathered in cluster V (27 genotypes); followed by cluster IV (11 genotypes); cluster VII (07 genotypes), cluster I (04 genotypes). Cluster II, III and IV each had two genotypes. Cluster VIII was a monogenotypic one. The intra-cluster distance was maximum with the cluster I. The genotypes grouped in this cluster may also be different genetically. On other hand, the genotypes grouped in the cluster IX may be similar for the traits of interest due to minimum intra-cluster distance. The inter-cluster distance was maximum between the clusters VI and cluster II. The genotypes gathered in these clusters might be different genetically and utilized in crossing programme to get heterotic hybrids and/ or superior recombinants (segregants).

Genetic divergence studies in foxtail millet [Setaria italica (L.) Beauv.

Fifty genotypes of foxtail millet were subjected to multivariate analysis through Mahalanobis’ D2 statistics (Tocher's method) and Wards’ minimum variance method. Both D2 analysis and Ward's method grouped the 50 foxtail millet genotypes into eight clusters each. However, the clusters are different in two different methods with respect to total number as well as genotypes included in each cluster. In D2 analysis, cluster III is the largest with 13 genotypes followed by cluster II, IV, I, VI, V, VII and VIII. Whereas in Ward's method, the cluster VI is the largest with 14 genotypes followed by, cluster VII, I, II, IV, V, III and VIII. There was no solitary cluster in Ward's minimum variance method, where as in Tocher's method, three clusters viz., cluster V, VII and VIII are solitary clusters. In both the methods, there is wide genetic diversity between the clusters. Considering the distribution of genotypes in both the methods it can be concluded that crosses, Ise-1605 × Ise-745 and Ise-1605 × Ise-1419 are having good chance of producing heterotic hybrids or transgressive segregants, depending on the gene action controlling the traits.

ECOLOGICAL TEST OF A NEW HALF-FAST ONION VARIETY FOR AN ANNUAL CULTURE IN THE REPUBLIC OF MARI EL

In terms of occupied areas, onion is on the third place in the world among vegetable crops, second only to tomato and watermelon. In Russia, onion is grown on an area of 88 to 96 thousand hectares of onions, and ranks third, yielding to cabbage and tomato.The increase in the production of onions is not only due to the increase in the areas occupied by the crop, but also due to increased yields. This is achieved by introducing new highly productive varieties and hybrids into production, increasing the overall cropping culture and the level of cultivation technology. Along with the creation of heterotic hybrids at the present time, the Russian Federation also continues to select varieties that show high rates when grown in a oneyear crop. The results of production tests of a new onion variety of Forward Selected Breeding VNIIO a branch of the FGBNU FNCO has shown that it is promising because it has a high yield potential, high quality of bulbs and excellent preservation in conditions of repositories with controlled conditions. Characterized by mid-maturity maturation. The period from full shoots to mass lodging of leaves is 110 days. In relation to the longitude of the day, the forward sort refers to a group of long-day bows. The bulb is bilobate, rounded and rounded – flat, with an average mass of 90-120 g. The color of the dry covering scales is yellow-brown, the succulent scales are greenish. The taste is semi-sharp. The dry matter content in the bulb during the test years was 11.0-12.0%.