我国40个小麦品种抗叶锈性研究

 选用11个具不同毒性基因组合的叶锈菌致病类型推导分析了1998~1999年度国家小麦区域试验40个品种所携带的抗叶锈病基因状况。在供试的39个已知抗叶锈基因(或基因组合)中,推导出Lr1、Lr2c、Lr3bg、Lr10、Lr13、Lr14a、Lr16、Lr23、Lr26、Lr32等10个抗叶锈基因,分布在24个品种中,有11个品种携带未知抗叶锈基因,5个品种不具有苗期抗叶锈基因。选用BBB、DHS、PGT和PHT等4个叶锈菌致病类型并设置5/10℃、15/20℃、25/30℃(黑暗/光照)3种不同的温度条件,研究了40个供试品种的抗性稳定性。结果表明,在这些品种中有15个品种的侵染型表现稳定或较稳定,3个品种表现为高温抗性,2个品种表现低温抗性,其余20个品种存在明显的品种、菌系和温度三者的相互作用;利用6个叶锈菌混合优势小种在田间进行成株期抗叶锈性鉴定结果表明,在40个供试品种中有21个品种具有良好的抗性,其中,至少有6个品种表现为慢锈性,有4个品种表现为明显的成株抗性,有4个品种可能携带成株抗性基因Lr34。文中还对几个主要抗叶锈基因的抗性特点及其利用价值等进行了讨论。

LEAF RUST RESISTANCE OF 40 WHEAT CULTIVARS IN CHINA

Genes for resistance to leaf rust were detected in 40 wheat cultivars originated from National Adaptability Test of Wheat Varieties in 1998～1999 using 11 isolates of Puccinia recondita f. sp. tritici wihch previously characterized for avirulence or virulence gene combination,respectively. Ten of the 39 test genes (or gene combination) were postulated to be present in 24 cultivars, and unknown resistance gene (or genes) in 11 cultivars. No genes for leaf rust resistance in the seedling stage were found in 5 cultivars. Stability of leaf rust resistance was tested in 40 wheat cultivars using BBB, DHS, PGT and PHT Puccinia triticina pathotypes under 5/10℃, 15/20℃ and 25/30℃ (dark/illumination)temperature ranges, separately. Asthe results indicated, 15 cultivars of 40 test cultivars displayed stable or basically stable infection type, high temperature resistance was detected in 3 cultivars, low temperature resistance was detected in 2 cultivars, the interactions of pathogen pathotype, wheat cultivars and temperature were detected in 20 rest cultivars. Adult plant resistance of 40 wheat cultivars was identified with 6 Puccinia triticina pathotypes in the field. Twenty-one cultivars displayed good resistance in the adult plant stage, among them, slow-rusting resistance was displayed in at least 6 cultivars and obvious adult plant resistance was shown in 4 cultivars. It was found that the leaf tip necrosis (LTN) symptoms were shown in 4 cultivars, which probably possessed adult plant resistant gene Lr34. Resistance features of several important Lr genes and their applicability were also discussed in the paper.