Heterosis For Yield Research Articles

Investigation of combining ability and heterosis in sorghum [Sorghum bicolor (L) Moench] genotypes under moisture stress areas

The most important prerequisite in sorghum crop improvement is the identification of suitable parents that can combine well and produce superior hybrids. However, a narrow genetic base, lack of potential hybrids and lack of information on the genetic components are the most important limiting factors for sorghum yield improvement. Therefore, the experiment was conducted to estimate the combining abilities and heterosis for yield and agronomic traits. A total of 42 sorghum genotypes were evaluated using an alpha lattice experimental design with two replications at Mieso and Kobo during the cropping season of 2019. Combined analysis of variance revealed highly significant differences due to genotypes for days to flowering, plant height, days to maturity, effective productive tillers, panicle exersion, panicle length, panicle width, panicle yield, grain yield and thousand seed weight traits. Based on general combining ability analysis, inbred lines P-9505 and P-9534 were identified as the best general combiners for both days to flowering and plant height traits; whereas inbred lines P-9501 and B5 were identified as the best general combiners for stay green traits. The hybrid crosses P-9534 x Melkam, B6 x ICRS-14 and MARC3 x Melkam were identified as the best specific combiners for grain yield, while the hybrid TX-623 x ICRS-14 was the best specific combiner for days to flowering, days to maturity, panicle length, panicle width and thousand-seed weight. The estimates of general and specific combining ability revealed the preponderance of non-additive gene action since the ratio of general combining ability to specific combining ability was less than unity for all the traits under study except for plant height. The maximum grain yield was obtained from the hybrids P-9534 x Melkam (6.32 tha-1), followed by the hybrids B6 x ICRS-14 (5.92 tha-1), TX-623 x ICRS-14 (5.88 tha-1), P9511 x Melkam (5.78 tha-1) and P-850341 x ICRS-14 (5.57 tha-1). Among the hybrids, B6 x ICRS-14 exhibited (112.41 %) yield advantage over the mid parents, hybrid TX-623 x ICRS-14 exhibited (68.71 %) yield advantage over the better parent, whereas P-9534 x Melkam exhibited (30.71 %) yield advantage over the standard check for grain yield. Finally, based on the mean yield performance, heterosis response and combining ability estimates for grain yield and its components, the hybrid crosses P-9534 x Melkam, B6 x ICRS-14, TX-623 x ICRS-14, MARC3 x Melkam, MARC3 x ICRS-14, P9511 x Melkam and P-850341xICRS-14 were found to be the most promising and potential hybrids that could be exploited commercially after critical evaluation for their superiority and yield stability across locations over the years.

Analysis of combining ability and extent of heterosis for yield and its related traits in bitter gourd (Momordica charantia L.)

Analysis of combining ability and extent of heterosis for yield and its related traits in bitter gourd (Momordica charantia L.)

Assessment of Heterosis and inbreeding Depression for Yield, and its Associated Components Traits in Rice (Oryza sativa L.)

The present investigation entitled was carried out at Main Rice Research Centre, Navsari Agricultural University, Navsari during kharif-2023 with an objectives to obtain information on manifestation of heterosis and extent of inbreeding depression involved in the inheritance of various yield attributing characters in rice (Oryza sativa L.). This study comprised three crosses using four diverse lines. The experimental material comprised of five generations each cross of pair parents i.e. P1, P2, F1, F2 and F3 of three different crosses were conducted in Compact Family Block Design with three replications during kharif 2023. For grain yield per plant all the three crosses (IRBB 55 × Mahisagar, IRBB 55 × GR-11 and IRBB 55 × TN-1) exhibited significant and positive relative heterosis as well as heterobeltiosis. Among them the highest mid parent heterosis of 39.67% and heterobeltiosis of 7.56% were exhibited by cross IRBB 55 × GR-11. This hybrid showed positive and significant relative heterosis for all the four important characters viz., productive tillers per plant, panicle length, grains per panicle and 100 grain weight. While, the inbreeding depression was found significant and positive for all the three crosses which is not desirable for grain yield per plant. Here, all the three crosses exhibited positive heterosis followed by positive inbreeding depression indicated that trait is under influence of non-additive type of gene action and heterosis breeding would be found rewarding for improvement for grain yield per plant.

Estimation of Heterosis for Plant Growth, Oil Content and Yield Related Traits in Indian Mustard [Brassica juncea (L.) Czern and Coss] Using Half Diallel

Genetic investigation was carried out diallel design for heterosis analysis studies the experimental material comprised with eight parents with two checks was carried out to identify high heterotic crosses and their relationship in Indian mustard. Several hybrids exhibited heterobeltiosis and standard heterosis for seed yield per plant and other characters. The heterosis analysis revealed substantial hybrid vigor across 28 hybrid crosses, with noteworthy improvements in traits such as earlier flowering, earlier maturity, and increased seed weight. The seed yield per plant exhibited better parent heterosis ranging from -20.71% to 16.28%, with five crosses yielding more seeds than their better parents. P3 (PM-22) X P8 (RH-749) was the best cross, with a 16.28% increase. Standard heterosis ranged from -38.72% to 35.14%, with ten crosses showing significant positive heterosis. The findings from this investigation provide crucial insights into the genetic performance and breeding potential of Indian mustard genotypes. The identified parental lines and cross combinations with desirable heterosis effects offer valuable resources for breeding programs aimed at developing high-yielding and resilient mustard varieties, contributing to the advancement of agricultural practices and crop improvement. The above best parent and best crosses can be used in hybridization and heterosis breeding respectively.

Performance of Provitamin a Maize Hybrids for Yield and Desirable Agronomic Traits

To find improved F1 hybrids for breeding procedures, the heterosis of maize hybrids must be determined. Therefore, to identify prospective hybrids for use in future provitamin A maize breeding systems, this study was carried out to evaluate the amount of standard heterosis for grain yield and related attributes. Fifteen provitamin A maize inbred lines were crossed through the diallel-II design. The resulting Eight four F1 hybrids along with four standard checks (BHQPY545, BH549, BH546, and BH547) were evaluated using RCBD (20 entries) and Alpha-Lattice Design (68 entries) with two replications during 2022/2023 main cropping season at Bako National Maize Research Center. Analysis of variance revealed significant variations for most of the traits indicating the existence of genetic variability. The Standard heterosis assessment noticed significant positive and negative heterosis for the majority of the traits investigated. Cross combinations over BHQPY 545, such as L10 × L3, L10 × L6, and L13×L12, demonstrated the largest proportion of traditional heterosis for grain yield (more than 25% yield advantage). Because BH546 and BH547 are normal maize with grain production potential, the majority of crossings yielded negative and significant results over commercial checks. The highest found heterosis for grain yield and associated factors indicated that maize genotypes' heterotic potential may be beneficial to boost yield. The findings of this study could be valuable for researchers looking to develop high-yielding provitamin A maize hybrids. As a result, possible hybrids might be recommended for commercial usage once the results have been verified by repeating the research over time and across places, as well as incorporating quality attributes analysis data.

Combining Ability and Heterosis for Yield and Yield Attributing Traits in Bitter Gourd

A study was conducted during Rabi 2022 and Kharif 2023 at the Department of Horticulture, University of Agricultural Sciences, Bangalore to develop 49 F1 hybrids through the utilization of line × tester mating design. The parents and developed hybrids along with standard check (Pusa Hybrid 6) were evaluated in Randomized Complete Block Design) and Alpha lattice design, respectively, for yield and yield attributing traits. The combining ability analysis revealed that among 14 parents, Pusa Rasdar, Pusa Do Mausami, Pusa Vishesh, Hirkani and Pant Karela 4 were identified as best general combiners for most of the studied yield and yield attributing traits. The estimates of heterosis revealed that the hybrids, Konkan Karali × Pant Karela 4 (45.45%), Konkan Tara × Pusa Do Mausami (23.48%), Pusa Rasdar × Phule Green Gold (126.87%) and Hirkani × Pusa Do Mausami (46.20%) were top performing hybrids over standard check for fruit length, diameter, average weight and number of fruits per vine, respectively. Similarly, Pusa Rasdar × Pant Karela 4 (127.06%), Priya × Pusa Do Mausami (101.05%), Punjab 14 × Pusa Do Mausami (100.53%) and Pusa Rasdar × Pant Karela 3 (97.61%) were top performing hybrids over standard check for yield per vine. These hybrids also recorded highest significant sca effects hence, considered as good specific combiners.

Exploitation of heterosis for fruit yield and its attributing traits in brinjal (Solanum melongena L.)

Exploitation of heterosis for fruit yield and its attributing traits in brinjal (Solanum melongena L.)

Combining Ability, Heterosis and Potence Ratio for Yield and Yield Components in Korean Double-Haploid, Progenies and Improved Rice Varieties in Nigeria

Rice is the most widely consumed staple crop in Africa and consumption continues to grow at a rapid pace with increasing population. Success in breeding programs are largely dependent on the genetic diversity of a crop. Genetic variability occurs due to genetic differences in individuals within a given population, which is the basis of plant breeding. Thus, if the genetic variability is well managed, diversity can result to permanent gains in the performance of the crop. The objectives of this study were to determine the interaction between grain yield and yield components and to conduct genetic studies on selected rice genotypes. The research was carried out at the University of Port Harcourt Faculty of Agriculture teaching and research farm. Thirteen (13) varieties were used which comprised 7 adapted Nigerian varieties and 6 Korean rice varieties in a randomized complete block design (RCBD) in three replications was established. All agronomic practices were carried out at appropriately crop phenology. North Carolina II mating design was used to perform crosses. Data was collected on 10 agronomic traits. All means were subjected to ANOVA, combining ability, Heterosis and Potence ratio were determined. The progenies from UPIA 2 x UPN 234, FARO 52 X UPN 266 and UPIA 3 X UPN 266 had the best phenotypic and genotypic expression and most of the hybrids had heterotic values than their parents. The results also showed ranges of dominance for genotypes. UPIA 1, UPIA 2, UPN 223, UPN 234 and UPN266 should be included in breeding programs because they showed the best GCA’s across most traits.

Genetic Evaluation of Heterosis and Combining Ability of Quality Protein Maize (Zea mays L.) Hybrids under Terminal Heat Stress Conditions

Background: The development of quality protein maize (QPM) hybrids tolerant to terminal stress environments has been an essential strategy for reducing the associated loss in grain yield. A study by Badu-Apraku et al., (2019) employed line × tester analysis in QPM breeding, highlighting its efficacy in selecting QPM hybrids. While QPM varieties resistant to disease, drought and environmental stresses have been developed conventionally, the adoption of improved QPM genotypes in farmers’ field is restricted mainly due to lack of proper team effort among maize breeders, farmers, agricultural extension workers and other relevant stakeholders. Methods: In line × tester mating design, six lines and three testers were crossed under heat stress environment and 18 F1s along with parental lines were evaluated along with check varietal during summer season, 2023, P.G research farm, CUTM, Paralakhemudi, Odisha. The objective of the current study was to evaluate parental lines and its crosses based on combining ability and heterosis. Result: ANOVA revealed significant to revealed significant differences for all the traits between parents, lines, testers and lines vs testers, except for cob height, chlorophyll content and canopy temperature. 𝛔2GCA/𝛔2SCA values for parents/hybrids recorded lower than unity for all the trait studied suggesting preponderance of non-additive gene action. Parental lines CML149, CML143 and CML330 are the best general combiners for early flowering, grain yield per plant and antioxidant status. Among eighteen crosses, two hybrids CML149 × CML330 and CML143 × CML193 recorded significant SCA effects for early flowering, grain yield per plant and antioxidant levels. Hybrids CML149 × CML330 (33.31%) and CML143 × CML193 (28.31%) noted significant standard heterosis for grain yield per plant over commercial check, HQPM-1. Hybrids CML149 × CML330 and CML143 × CML193 were resilient to terminal heat stress as they didn’t exhibit signs of leaf firing, tassel blast, root lodging and loss of yield.

Estimation of Heterosis and Inbreeding Depression for Yield Related and Quality Traits in Forage Sorghum [Sorghum bicolor L. (Moench)

The present study was conducted at GBPUAT Pantnagar to study the heterosis and inbreeding depression for nine yield related and three quality traits which consisted of seventy F1 crosses developed through line x tester mating design involving ten cytoplasmic male sterile (female) lines and seven pollinator (male) lines during Kharif 2018 and 70 F2s developed by selfing of F1 crosses during Kharif 2019 in random block design (R.B.D.) with three replications. Observations were recorded on plant height, stem girth, number of leaves per plant, leaf length, leaf width, leaf area, leaf: stem ratio, total soluble solids, HCN content, green fodder yield per plot, dry fodder yield per plot, and protein percent. The observed F1data was analyzed for mid parent heterosis, heterobeltiosis and standard heterosis whereas F2data was analyzed for inbreeding depression. The large number of crosses exhibited heterosis and inbreeding depression in desired direction for all yield related and quality traits under study which indicated the presence of additive as well as non-additive gene actions. The crosses ICSA 271 x PC 5, ICSA 276 x CSV-15, 993100 A x 04K 668, 11 A2 x 04 K 693, ICSA 469 x 04 K 668, ICSA 293 x 01 K 733, SPA2 94012 x 04 K 700, ICSA 293 x CSV-15, SP 55609 A x UPMC-8, and 993100 A x 04 K 700 exhibited high mean performance for all the traits under study coupled with high heterosis in desired direction.

Utilisation of GMS lines for production ofheterotic bacterial wilt resistant hybrids in <i>Tagetes</i> spp.

The study was conducted using six testers, of which two (KAU M-1 and KAU M-2) were completely bacterial wilt resistant, and four genetic male sterile lines (GMS), in a line x tester model and further the F1 hybrids were evaluated in a bacterial wilt sick plot for various vegetative, floral and yield parameters along with their response to wilt incidence. Field evaluation for bacterial wilt resistance revealed that out of 24 hybrids, 13 hybrids involving KAU M-1 and KAU M-2 as testers exhibited bacterial wilt resistance. Analysis on heterosis for various characters viz., vegetative, floral, yield and total carotenoids content showed significant heterosis for many of the hybrids over mid parent, better parent and the check variety. The highest standard heterosis for yield was observed for the interspecific hybrid KU Ms-6 xx KAU M-47 (190.84%) followed by an intraspecific hybrid KAU Ms-42 x KAU M-2 (70.93%). Based on the wilt resistance and heterotic performance, these two hybrids can be suggested for commercial cultivation in wilt affected areas.

Seed development-related genes contribute to high yield heterosis in integrated utilization of elite autotetraploid and neo-tetraploid rice.

Autotetraploid rice holds high resistance to abiotic stress and substantial promise for yield increase, but it could not be commercially used because of low fertility. Thus, our team developed neo-tetraploid rice with high fertility and hybrid vigor when crossed with indica autotetraploid rice. Despite these advances, the molecular mechanisms underlying this heterosis remain poorly understood. An elite indica autotetraploid rice line (HD11) was used to cross with neo-tetraploid rice, and 34 hybrids were obtained to evaluate agronomic traits related to yield. WE-CLSM, RNA-seq, and CRISPR/Cas9 were employed to observe endosperm structure and identify candidate genes from two represent hybrids. These hybrids showed high seed setting and an approximately 55% increase in 1000-grain weight, some of which achieved grain yields comparable to those of the diploid rice variety. The endosperm observations indicated that the starch grains in the hybrids were more compact than those in paternal lines. A total of 119 seed heterosis related genes (SHRGs) with different expressions were identified, which might contribute to high 1000-grain weight heterosis in neo-tetraploid hybrids. Among them, 12 genes had been found to regulate grain weight formation, including OsFl3, ONAC023, OsNAC024, ONAC025, ONAC026, RAG2, FLO4, FLO11, OsISA1, OsNF-YB1, NF-YC12, and OsYUC9. Haplotype analyses of these 12 genes revealed the various effects on grain weight among different haplotypes. The hybrids could polymerize more dominant haplotypes of above grain weight regulators than any homozygous cultivar. Moreover, two SHRGs (OsFl3 and SHRG2) mutants displayed a significant reduction in 1000-grain weight and an increase in grain chalkiness, indicating that OsFl3 and SHRG2 positively regulate grain weight. Our research has identified a valuable indica autotetraploid germplasm for generating strong yield heterosis in combination with neo-tetraploid lines and gaining molecular insights into the regulatory processes of heterosis in tetraploid rice.

Understanding combining ability, heterosis and relationships of pod yield and yield contributing traits in groundnut (Arachis hypogaea L.)

Understanding combining ability, heterosis and relationships of pod yield and yield contributing traits in groundnut (Arachis hypogaea L.)

Unlocking the Genetic Potential by Assessing Combining Ability and Heterosis for Yield and its Component Traits in Sunflower (Helianthus annuus L.)

The present investigation was executed with two lines and 12 testers along with 24 F1s and check NDSH 1012 for six yield and its component traits to ascertain the combining ability and heterosis. The analysis of variances showed highly significant differences among the parents for all the characters except for seed yield per plant and oil content implying the presence of significant variability and diversity among the parents. Among the two lines, ARM-243A was observed as best general combiner for head diameter, seed yield per plant and oil content. The tester, NDI-56 was found ato be good general combiner for head diameter and seed yield per plant. Out of 24 F1s evaluated, two crosses viz., CMS-17A X NDI-35 and CMS-17A X NDI-52 were recorded as good specific combiners for seed yield per plant and head diameter, respectively. The heterosis analysis revealed that 10 hybrids recorded positive significant mid parent, better parent and standard heterosis for seed yield per plant. Hence, the crosses CMS-17A X NDI-35 and CMS-17A X NDI-52 are advanced for direct selection to increase vigour gain.

Analysis of Heterosis and Stability in Brinjal at Multi-locations of Gujarat for Yield and its Attributing Traits

Background: Brinjal is the important vegetable crop. The extensive use of heterosis in vegetable crops has led to the creation of numerous high-yielding hybrid cultivars. Newly developed hybrids should also be tested across environments to develop region specific hybrids or hybrid for all the regions. Methods: The purpose of the present experiment was to develop region-specific brinjal (Solanum melongena L.) hybrids through line ´ tester design and to gather information on heterosis and stability for fruit yield and associated characters at multiple locations of viz., Sardarkrushinagar, Jagudan and Bhiloda under the jurisdiction of S.D.A.U. in late rabi 2021–2022. Result: There were noticeable genetic differences in the material for the majority of the traits. Several crosses were identified which showed desirable heterosis for at least one yield component in individual and pooled over locations. Fruit yield per plant is the most important trait. Hybrid ‘ISD-006 × GOB-5’ showed the highest fruit yield and maximum standard heterosis for fruit yield per plant, fruit girth, fruit weight, total soluble solids and chlorophyll content index. The interaction of G × E was highly significant for the majority of characters suggesting the differential response of experimental material to the varied locations. Stability analysis suggested ‘ISD-006 × GAB-6’, ‘JDNB-16-1 × GOB-1’ and ‘ABSR-2 × GAB-6’ as the top three stable crosses for fruit yield per plant. Overall, ‘ISD-006 × GRB-5’ appeared to be an outstanding cross for fruit yield and its attributing traits in terms of heterobeltiosis and standard heterosis in individual and pooled environments. As well as it was found to be average stable for four major traits and stable in favourable environments for fruit weight and yield per plant. Also, incorporating hybrids identified in this experiment might potentially result in transgressive segregants in brinjal.

Estimation of Heterosis and Heritability for Fruits Yield and Quality Characters in Squash (Cucurbita Pepo L.) at Two Sowing Dates under Greenhouse Conditions

Estimation of Heterosis and Heritability for Fruits Yield and Quality Characters in Squash (Cucurbita Pepo L.) at Two Sowing Dates under Greenhouse Conditions

Combining ability and genetic distance analysis of mid altitude sub-humid agroecology adapted maize inbred lines for high grain yield

Understanding the combining ability effects, heterosis, and genetic relationships between parental lines would be helpful in the maize breeding program to develop high-yielding and genetically stable maize varieties for various contrasting environments. Hence, the objective of this study was to estimate combining ability effects, heterosis, genetic distance (GD) and associations for grain yield and other agronomic traits. Forty-five F1 diallel crosses, four commercial checks, and ten inbred lines were evaluated at Bako and Jima Agricultural Research Centers, Ethiopia. Significant differences were observed among environments, genotypes and genotype by environment interaction for grain yield and almost all studied agronomic traits. Combining ability analysis showed both additive and non-additive gene effects significantly controlled grain yield and all other studied traits. The preponderance of general combining ability (GCA) effects indicates the importance of additive gene action inheriting most agronomic traits. Lines L2, L7, and L9 were the best combiners for grain yield, whereas lines L3 and L4 had desirable GCA values to improve days to flowering and plant height. Among the top ten crosses, L6 × L9, L6 × L7 and L4 × L9 were good specific combiners and had 18.8 %, 17.2 % and 16.2 % grain yield advantage over the best check, BH546. These hybrids also had high mid and better-parent heterosis compared with other crosses. The associations of GD with mean of F1 and SCA effects were positive and highly significant for grain yield and some other traits. In contrast, correlations of GD with mid and better parent heterosis were non-significant for grain yield and most other traits. The results of this study are particularly useful for breeders who envisage combining conventional and molecular methods.

Unearthing hybridization opportunities for augmenting biomass yield and harvest index in rajmash (Phaseolus vulgaris L.)

In present study, 21 F1 hybrids derived from crossing between seven female genotypes and three male testers following a line × tester mating design were evaluated for analyzing the component of genetic variation and heterosis of yield contributing traits. The components of variances due to gca and sca revealed the predominance of non-additive gene action for biomass and harvest index. The average better parent heterosis (BPH) and standard heterosis (SH) for Biomass yield (BY) was 43.71 and 114.67, respectively, and the average BPH and SH for the Harvest index (HI) was -13.04 and -20.45, respectively. The higher magnitude of the BPH and SH recorded for BY indicated that the scope for increasing the HI in Rajmash is limited and that further increases in productivity have to come mainly through enhanced BY. The parent RR21-01 and GR 1 were good general combiners for biomass, TRCR 3, TRCR 2, SKAU-R-19 and RKR 1033 for harvest index. Cross combinations IPR-277- 19 × HUR recorded positively significant sca effect for BY and IPR-277-19 × GR, TRCR 3 × GR 1, TRCR 2 × GR 1, IPR-205-19 × HUR, IPR-277-19 × GR 1, SKAU-R-19 ×RKR 1033, RR-21-01 × HUR and RR-21-12 × GR 1 for HI. These results demonstrate that the selection of parents should not only be based on per se performance but also on combining ability and heterosis for achieving genetic improvement in Rajmash,

Natural variations of heterosis-related allele-specific expression genes in promoter regions lead to allele-specific expression in maize

BackgroundHeterosis has successfully enhanced maize productivity and quality. Although significant progress has been made in delineating the genetic basis of heterosis, the molecular mechanisms underlying its genetic components remain less explored. Allele-specific expression (ASE), the imbalanced expression between two parental alleles in hybrids, is increasingly being recognized as a factor contributing to heterosis. ASE is a complex process regulated by both epigenetic and genetic variations in response to developmental and environmental conditions.ResultsIn this study, we explored the differential characteristics of ASE by analyzing the transcriptome data of two maize hybrids and their parents under four light conditions. On the basis of allele expression patterns in different hybrids under various conditions, ASE genes were divided into three categories: bias-consistent genes involved in basal metabolic processes in a functionally complementary manner, bias-reversal genes adapting to the light environment, and bias-specific genes maintaining cell homeostasis. We observed that 758 ASE genes (ASEGs) were significantly overlapped with heterosis quantitative trait loci (QTLs), and high-frequency variations in the promoter regions of heterosis-related ASEGs were identified between parents. In addition, 10 heterosis-related ASEGs participating in yield heterosis were selected during domestication.ConclusionsThe comprehensive analysis of ASEGs offers a distinctive perspective on how light quality influences gene expression patterns and gene-environment interactions, with implications for the identification of heterosis-related ASEGs to enhance maize yield.

Understanding combining ability, heterosis and relationships of pod yield and yield contributing traits in groundnut (Arachis hypogaea L.)

Understanding combining ability, heterosis and relationships of pod yield and yield contributing traits in groundnut (Arachis hypogaea L.)