为给高产区小麦抗病性遗传改良提供新的育种材料,以高产小麦品种科农9204(Kn9204)为母本,以黑麦品种德国白粒(German White)和小偃6号杂交后代BC2F4选系BC01-7-1为父本杂交,并以科农9204为轮回亲本回交两次,最终选育出抗条锈病的育种新材料9204R。本研究考察了9204R的主要农艺性状、苗期和成株期对条锈病的抗性。结果表明,9204R田间农艺性状优良,穗粒数表现为超亲,小区产量比对照品种石4185高1.7%。苗期对CYR29、CYR30、CYR31、CYR33、SU11-4和SU11-11等条锈病生理小种表现为免疫,对CYR32表现为感病;成株期对混合小种(CYR29、CYR31、CYR32和CYR33)表现为高抗。应用连续C-分带-基因组原位杂交(GISH)技术对9204R进行染色体组成分析,发现9204R含有1对1RS/1BL易位染色体。应用微卫星(SSR)分子标记对科农9204和9204R进行分析,共有1对位于1RS和4对位于1BS上的引物扩增出差异条带,推测2个基因型的1RS染色体来源不一致,9204R的1RS可能来源于黑麦品种德国白粒。
Stripe rust is one of the destructive diseases of wheat(T.aestivum L.) throughout the world;developing disease resistant cultivars is an effective approach to prevent epidemics of the disease.To increase the yield potential of the 1RS/1BL translocations,high-yield cultivar Kn9204 was crossed with a BC2F4 line BC01-7-1 derived from distant hybridization between common wheat(cv Xiaoyan No.6) and rye(Secale cereale L.cv German White).The F1 was backcrossed twice with Kn9204 as the recurrent parent and systematically selected for six generations.After serious individual discrimination with inoculation of P.striiformis at seedling and adult plant stage,respectively,9204R was eventually developed,which is of desirable agronomic artributes and high resistance to stripe rust.In plot yield trial,9204R yielded 1.7% more than the regular control Shi 4185,a cultivar grown in large area in north China.Compared with its parent Kn9204,9204R has more grain number per spike.For stripe rust resistance,seedling of 9204R was immune to most races of P.striiformis such as the major epidemic races in China CYR29,CYR30,CYR31,CYR33,SU11-4 and SU11-11,and the infection grade to CYR32 was lower than its recurrent parent Kn9204.The adult of 9204R was highly resistant to CYR29,CYR31,CYR32 and CYR33.Sequential C-banding and GISH(genomic in situ hybridization) was employed to analyze the chromosome compositions in somatic cells to identify cytological genetic basis of 9204R.The result revealed that 9204R was 1RS/1BL homozygous like Kn9204,which belonged to Lovrin derived lines.Since the old 1RS lines derived from Lovrin had lost resistance to the current prevalent stripe rust races,the 1RS identified in 9204R was deduced to come from "German White" and give 9204R resistance to the new races of P.striiformis.SSR markers were used to analyze the differences between 9204R and its parent Kn9204.The results indicated that 1 pair of primer on 1RS and 4 pairs of primers on 1BS could amplify different bands between Kn9204 and 9204R