Combining Ability and Genetic Analysis of Grain Yield and its Component Traits in Maize Lines Differing in Turcicum Leaf Blight (TLB) Response
Susmita Cherukuri
Department of Genetics and Plant Breeding, Professor Jayashankar Telangana Agricultural University (PJTAU), Hyderabad-500 030, Telangana, India and Winter Nursery Centre, ICAR-Indian Institute of Maize Research, Hyderabad-500 030, Telangana, India.
Vipparthi Hemalatha
Department of Genetics and Plant Breeding, Professor Jayashankar Telangana Agricultural University (PJTAU), Hyderabad-500 030, Telangana, India.
Kondajji Rangappa Yathish *
Winter Nursery Centre, ICAR-Indian Institute of Maize Research, Hyderabad-500 030, Telangana, India.
Chikkappa Gangadhar Karjagi *
Regional Maize Research and Seed Production Centre, ICAR- Indian Institute of Maize Research, Begusarai- 851 101, Bihar, India.
Mallikarjuna N
AICRP on Maize, Zonal Agricultural Research Station, V C Farm, Mandya-571 405, Karnataka, India.
Prema G U
AICRP on Maize, Main Agricultural Research Station, University of Agricultural Sciences, Dharwad-580 005, Karnataka, India.
Rakesh Kumar Develash
Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Hill Agricultural Research and Extension Centre, Bajaura-175 125, Himachal Pradesh, India.
Omkar Kumar
Regional Maize Research and Seed Production Centre, ICAR- Indian Institute of Maize Research, Begusarai- 851 101, Bihar, India.
Sunil Neelam
Winter Nursery Centre, ICAR-Indian Institute of Maize Research, Hyderabad-500 030, Telangana, India.
Sushil Pandey
ICAR-National Bureau of Plant Genetic Resources, Pusa Campus, New Delhi-110 012, India.
Jyoti Kumari
ICAR-National Bureau of Plant Genetic Resources, Pusa Campus, New Delhi-110 012, India.
Sherry Rachel Jacob
ICAR-National Bureau of Plant Genetic Resources, Pusa Campus, New Delhi-110 012, India.
Badal Singh
ICAR-National Bureau of Plant Genetic Resources, Pusa Campus, New Delhi-110 012, India.
*Author to whom correspondence should be addressed.
Abstract
The present study employed a 9 × 9 half-diallel mating design to estimate GCA and SCA effects among TLB-contrasting maize inbred lines, enabling the precise identification of superior parents and hybrid combinations for yield enhancement. Nine inbred lines were crossed during rabi 2023-24, and the resulting hybrids along with their parents were evaluated during kharif 2024 at Mandya and Dharwad in RBD with two replications for phenology, plant traits, grain yield and its components. A combined analysis across locations was conducted to assess parental and hybrid performance and to estimate key genetic parameters underlying trait inheritance. Combining ability ANOVA revealed significant GCA and SCA effects for most traits, indicating the contribution of both additive and non-additive gene actions, as well as substantial genetic variability among crosses. Significant site × genotype interactions for several traits further emphasized the influence of environmental variation on additive and dominance effects, underscoring the need for multi-environment testing to identify stable, high-performing genotypes. Genetic parameter estimates indicated that flowering traits were predominantly governed by additive gene action, whereas plant stature, major yield components, and grain yield were largely influenced by non-additive effects, as supported by GCA-SCA ratio, Baker’s ratio, and variance components. Although broad-sense heritability was moderate to high for most traits, narrow-sense heritability remained low, suggesting limited additive variance and highlighting the relevance of hybrid breeding, recurrent selection, or marker-assisted approaches over direct phenotypic selection. GCA analysis identified P5 as a strong general combiner for multiple yield traits, while P6 was superior for early flowering and reduced plant height. SCA analysis highlighted promising cross combinations, particularly P3 × P7, P2 × P6, P6 × P8, and P3 × P5 for improving key yield-related traits and overall maize productivity.
Keywords: Additive effects, combining ability, diallel analysis, non-additive effects, yield