Importance of genotype xenvironmental interactions for traits of economic importance in White Leghorn layers
P. NALLAPPA 1, G.R. LOKNATH2, K.S. PRATHAP KUMAR 2
AND N. RAJESWARA RAO 1
1 Central Poultry Development Organisation (Southern Region), Bangalore 80
2 Department of Poultry Science, U.A.S., Bangalore 24
An investigation was undertaken on three white leghorn lines namely, T (N: 4078), S (N:4156) and M (N:4010) in order to study their genetic architecture, response from selection and genetic divergence. Data from two years (1992-93 and 1993-94), provided from three hatches per year in each line were evaluated for body weight at 20 and 40 weeks of age, age at sexual maturity, egg production up to 40 weeks of age, egg weight, egg mass, fertility and hatchability on total and fertile eggs set. The lines had undergone long term IDS method of selection (Osborne, 1957) for egg production. Variances due to genotypes (lines) and environments (year and hatch) were significant. All the lines performed differently during the two years in each hatch. The line x hatch and line x year interactions were significant suggesting there is considerable environmental x genotypic interactions for economically important traits in white leghorn layers.