Yellow Rust Resistance in Advanced Lines and Commercial Cultivars of Bread Wheat from Ethiopia

Abstract

Bread wheat (Triticum aestivum L.) cultivars often succumb to yellow rust (Puccinia striiformis f.sp. tritici Westend.) soon after their release for commercial production, especially in the highlands of south-eastern Ethiopia. Variety diversification may buffer the ever evolving new races of the yellow rust pathogen. The objective of this study was to characterize seedling yellow rust resistance in 21 advanced bread wheat lines and 20 cultivars from Ethiopia. Yellow rust infection types (ITs) produced on test wheat lines and cultivars from nine yellow rust races were compared with ITs produced on standard differential lines that differed for specific yellow rust resistance genes. The experiment was conducted at seedling stage under greenhouse conditions in Goettingen, Germany during 2001. The result indicated that most of the advanced bread wheat lines possess different yellow rust resistance genes when compared to the commercial cultivars. Seedling genes Yr1, Yr2, Yr3V, Yr4, Yr6 and Yr17 with or without Yr9 were postulated to be present in 11 advanced lines. However, only Yr7 and Yr9 were postulated to be present in five of the commercial bread wheat cultivars. The newly identified resistance sources could be of great importance for enhancing the genetic base of resistance of bread wheat to yellow rust in Ethiopia.

Screening of Wheat Genotypes (<i>Triticum spp</i>) Against Yellow Rust in Arsi, Ethiopia

“…The bread wheat variety laketch was the most susceptible to yellow rust at meraro followed by kubsa and Dashen (Table 2) and kubsa was the most susceptible varieties at kulumsa (Table 1). The two varieties KBG-01 and and Meraro were resistance to yellow rust which has similar result (not contradicting) with previous research [3].…”

“…Out of the advanced bread wheat genotypes, 8.3.8 (B) and 11.6.24 were released to farmers in Ethiopia, with names KBG-01 and Meraro, during 2001 and 2005 respectively. The former was resistant to the nine races and, based on F2 segregation ratio, two complementary recessive genes, Yr9+ and Yr7 were postulated, [3].…”

Potential of Synthetic Hexapod Wheat for Stripe Rust Resistance in Ethiopia

“…A large proportion of seedling resistance genes exhibit phenotypes of major effect and with varying infection types whereas most of the APR genes are partial in effect with varying levels of disease severity [41]. Lines that possess durable rust resistance have been described as those that are susceptible at the seedling stage but resistant at the adult plant stage [42,43]. About 40% the SHW evaluated displayed Adult plant resistance (APR) phenotype at the two sites, Meraro and Kulumsa in Ethiopia.…”

Genetic architecture of adult-plant resistance to stripe rust in bread wheat (Triticum aestivum L.) association panel

“…Yellow rust is the most widespread disease in the highlands of Ethiopian as a result of which 36% to 100% wheat yield loss has been reported (Badebo and Bayu, 1992;Hailu and Fininsa, 2009;Ayele and Muche, 2019). In the highlands and mid-altitude regions of Ethiopia, yellow rust was to blame for the collapse of the dominant wheat varieties, including Laketch in 1977, Dashen (a well-liked high-yielding variety with the Yr9 gene) in 1988and 1994, Wabe in 1998(Badebo and Bayu, 1992, and Galema and Kubsa in 2010 (Tadesse et al (2018). In 2010, stripe rust epidemics occurred in all major wheat-growing areas of Ethiopia, causing large yield losses (Solh et al, 2012;Dembel, 2014).…”