Estimation of gene effects and combining ability of latent period of stripe rust in advanced lines of wheat

Four advanced breeding lines of wheat which had appeared to be resistant to stripe rust in the past years along with a susceptible variety, Bolani, were intercrossed in all combinations of a half-diallel design. Seedlings were grown in greenhouse until the first leaves fully expanded and then inoculated with two pathotypes (races) ۶E۱۳۴A+ and ۱۳۴E۱۴۸A+, separately. Days to the first pustule eruption was recorded as latent period. Diallel analysis was performed by two methods of Griffing, and Jinks and Hayman. M-۷۸-۱ and M-۷۸-۱۰ were known as the best general combiners for longer latent period. Results of the analysis of variance of Wr+Vr and Wr-Vr, Wr/Vr regression analysis and estimates of genetic parameters indicated the importance of both additive and non-additive gene effects. Broad-sense heritability was ۹۸% for both pathotypes. Narrow-sense heritability was ۶۵% and ۸۰% for ۶E۱۳۴A+ and ۱۳۴E۱۴۸A+ pathotypes, respectively.

Keywords:

Stripe rust , wheat , Resistance , latent period