The Reaction of Bread Wheat Lines and Varieties to Stripe Rust at Seedling and Adult Plant Growth Stages

Abstract

A total of 218 commercial bread wheat varieties and advanced lines were evaluated for their reaction to stripe rust (Puccinia striiformis Westend f. sp. tritici) isolates at seedling stage, and these entries were also exposed to natural infestation at Meraro,
Arsi, during the 1995 and 1996 cropping seasons. Relatively high proportions of the entries (25.5%) were susceptible to the ‘Dashen’ isolate while susceptibility to the ‘K 6295-4A’ isolate was less than 7%. The commercial bread wheat varieties such as ‘ET 13’, ‘K 6295-4A’, and ‘Enkoy’ were resistant to the ‘Dashen’ isolate but were susceptible to the ‘K 6295-4A’ isolate at the seedling stage. The field test results indicated that more than 60 % of the entries were resistant to leaf and spike infection during both seasons. The severity of stripe rust on ‘ET 13’, ‘Enkoy’ and ‘K 6295-4A’ was relatively low when compared with ‘Dereselign’ which was highly susceptible. The majority of the advanced lines which showed complete resistance were from the CIMMYT crosses such as ‘Lira S’, ‘Chilero S’, and ‘Carpentero S’. These lines have been reported to be resistant in earlier investigations, and are suggested to be
incorporated in the crossing program.