#general combining ability

Pearl millet (Pennisetum glaucum L.) is a vital cereal crop for arid and semi-arid regions, where enhancing productivity and stability remains a breeding priority. Recent advancements in heterosis breeding, combined with comprehensive analyses of general combining ability (GCA) and specific combining ability (SCA), have significantly contributed to the development of high-yielding, stress-tolerant hybrids. By identifying superior parental lines with strong GCA effects, the use of heterosis for grain yield, earliness, biomass output, and nutritional quality has been reinforced. Breeders may choose parents with advantageous allelic combinations for both additive and non-additive genetic effects thanks to the increased precision of combining ability prediction provided by molecular markers and genomic selection. Utilizing multi-environment trials, stability analysis guarantees hybrids’ tolerance to changing climatic and edaphic conditions, which is essential for reducing yield variations. To address issues of food security and nutrition, current research trends center on combining high-throughput phenotyping, genomic technologies, and bio-fortification techniques with heterosis breeding. Breeders may create hybrids with high yield potential and consistent performance in a variety of conditions by integrating stability criteria with GCA and SCA research. Utilizing climate-resilient germplasm, taking use of untapped genetic variety, and using genomic-assisted breeding to create hybrids quickly are all promising avenues for the future. To ensure sustainable production in marginal agro-ecosystems, a methodical strategy that incorporates heterosis, combining ability, and stability studies will be essential in speeding up pearl millet development.

Cotton breeding has progressed significantly with the integration of conventional and molecular approaches aimed at enhancing yield, fiber quality, and adaptability to biotic and abiotic stresses. In order to create superior cotton hybrids, heterosis, or hybrid vigor, is essential. Both intraspecific and interspecific crossings exhibit notable improvements in component characteristics and seed cotton production. Finding prospective parental lines and cross combinations requires evaluating both general combining ability (GCA) and specialized combining ability (SCA). While SCA denotes non-additive gene effects, namely dominance and epistasis, which contribute to heterotic performance in particular crossings, GCA represents additive gene effects, which are frequently associated with the accumulation of advantageous alleles across generations. Heterosis exploitation is widely used in cotton hybrid breeding projects to evaluate GCA and SCA through top-cross, line × tester, and systematic diallel studies. The accuracy of detecting high GCA parents and better SCA hybrids has increased because to developments in genomic selection, marker-assisted selection, and biotechnological treatments. In order to maximize heterosis expression, increase genetic variety, and maintain production in the face of climatic unpredictability, future opportunities lay in combining genomic methods with traditional breeding. The next stage of cotton enhancement may be fueled by a smart mix of utilizing molecular breakthroughs, optimizing combining ability, and taking use of heterosis.

Brassica is an important oilseed crop. The genetic basis of plant height, no. of primary branches, no. of pods per plant, no. of pods per raceme, pod length, beak length and 1000 grain weight in brassica lines was estimated through combining ability by using line × tester (5 × 3) analysis. The presence of a significant difference in the means squares of analysis of variance indicated that all the genotypes genetically differed from each other for investigated traits. The super value of Ϭ²sca over Ϭ²gca revealed the presence of non-additive gene action for all studied parameters. The results for the gca effect concluded that BN3, BN4, and BC27 had higher gca effect for many traits. Lines exhibited greater contribution then testers for every trait except beak length. The F1 hybrid of BN3 × BC27 was superiors in sca effect for many of the investigated traits. The other best performing hybrids were BN3 × BC7, BN4 × BC27, BCAC × BC7, BCAC × BC27, BCAA × BC7, BCAA× BC27, and BC44 × BC7. This research described the importance of the non-additive type of gene action in brassica and suggested its use in the breeding programs for evaluating genetic variations. The study presented useful information about gene action for various yield controlling traits. Thus, concluded that the use of lines having superior gca and sca in the yield improvement plans for brassica will help in obtaining improved cultivars.