Abstract

Stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is a major disease of wheat. In Kenya, Pgt has caused sporadic but serious losses to farmers since large-scale wheat production began in the early twentieth Century. Breeding for stem rust resistance in Kenya has been conducted since 1910. Mutants of Pgt are common in Kenya as large pathogen populations survive on wheat crops planted throughout the year, with virulence to effective major genes developing shortly after release of resistant cultivars. Gene Sr31 was first deployed in Kenya in ‘Kenya Pa’a’ in 1982 and subsequently in ‘Duma’ in 1993, the latter grown on large acreage. Virulence to Sr31 was first detected in Uganda in 1998, in what became known as Pgt-Ug99 (race TTKSK). Virulence to Sr31 may have occurred earlier in Kenya, but Ug99 was first reported in 2001. Race TTKSK has migrated across East Africa and to Yemen and Iran, spreading to 13 countries with 13 race variants. Other Pgt races (TKTTF, TTRTF, TTTTF) with broad virulence were recently detected in Kenya, likely originating from central Asia. A ‘Sounding the Alarm’ message from Norman Borlaug in 2005 triggered extensive research on worldwide virulence in Pgt, and on finding, characterizing, and developing molecular markers for Sr genes effective to Ug99-lineage pathotypes of Pgt. While fungicides can control Pgt, the best strategy uses host resistance. The best gene stewardship practice to provide enduring resistance combines effective major and minor adult plant resistance (APR) genes prior to release of new wheat cultivars.

摘要

茎锈病，由禾本科 Puccinia graminis f.引起。sp. 小麦( Pgt ) 是小麦的主要病害。在肯尼亚，自从 20 世纪初开始大规模小麦生产以来，Pgt给农民造成了零星但严重的损失。育种肯尼亚秆锈病抗性已进行了自1910年突变体PGT是共同在肯尼亚大病原体群体对小麦庄稼生存种植一年四季，与毒力有效的主基因抗病品种的发行之后开发。Gene Sr31于 1982 年首次部署在肯尼亚的“Kenya Pa'a”，随后于 1993 年在“Duma”部署，后者大面积种植。对Sr31 的毒力1998 年在乌干达首次被发现，后来被称为Pgt -Ug99（种族 TTKSK）。Sr31 的毒力可能更早在肯尼亚发生，但 Ug99 于 2001 年首次报道。种族 TTKSK 已迁移到东非、也门和伊朗，传播到 13 个国家的 13 个种族变体。其他PGT比赛（TKTTF，TTRTF，TTTTF）具有广泛的毒力在肯尼亚，来自中亚的起源可能是最近检测。A“拉响警报”，2005年从博洛格消息引发了对全球毒力广泛的研究PGT，并发现，特征，发展分子标记锶基因有效的Ug99真菌谱系致病类型PGT. 虽然杀菌剂可以控制Pgt，但最好的策略是使用宿主抗性。提供持久抗性的最佳基因管理实践在新小麦品种发布之前结合了有效的主要和次要成株抗性 (APR) 基因。