Kandel Yuba R, Glover Karl D, Tande Connie A, Osborne Lawrence E
Plant Science Department, South Dakota State University, Brookings 57007.
Pioneer Hi-Bred International, Brookings, SD 57006.
Plant Dis. 2012 Dec;96(12):1743-1748. doi: 10.1094/PDIS-03-12-0303-RE.
Bacterial leaf streak (caused by Xanthomonas campestris pv. translucens) has reemerged as a potential threat in spring wheat (Triticum aestivum) production areas in the northern Great Plains. As with other foliar bacterial diseases, chemical control under field situations is neither economical nor practical. Development of resistant genotypes will be needed for adequate management of the disease. There is currently limited information on sources of resistance in hard spring wheat germplasm. The main objective was to develop and apply a robust screening tool for evaluating germplasm against bacterial leaf streak, and to identify resistance sources for this disease. Inoculated field experiments were conducted in Brookings and Codington Counties, SD in 2009 and 2010 using a virulent local isolate (XctSD-017) inoculated after tillering stage. Forty-five hard red spring wheat genotypes with diverse genetic backgrounds were evaluated for disease severity, with ratings made at 7-day intervals from heading through dough stage. Results of this study showed clear differences in level of resistance among the 45 genotypes, with no immunity expressed. SD4205 was found resistant to the disease with the lowest area under the disease progress curve across location-years. Other genotypes showing moderate levels of resistance included SD4148, SD4176, 'Alsen', SD4023, 'Faller', SD4024, 'Knudson', and SD4199. Grain weight was negatively correlated to disease, as was days to heading. The resistance identified appeared to be quantitative in nature and was expressed through slower disease progress and reduced severity.
细菌性条斑病（由野油菜黄单胞菌小麦致病变种引起）已再度成为大平原北部春小麦（普通小麦）产区的一个潜在威胁。与其他叶部细菌病害一样，在田间情况下进行化学防治既不经济也不实用。需要培育抗病基因型才能对该病害进行有效管理。目前关于硬粒春小麦种质资源中抗病源的信息有限。主要目标是开发并应用一种强大的筛选工具来评估种质对细菌性条斑病的抗性，并鉴定该病害的抗病源。2009年和2010年在南达科他州布鲁金斯县和科丁顿县进行了接种田间试验，使用一种毒性强的当地分离株（XctSD - 017）在分蘖期后进行接种。对45个具有不同遗传背景的硬红春小麦基因型进行了病害严重程度评估，从抽穗期到面团期每隔7天进行评级。本研究结果表明，45个基因型之间的抗性水平存在明显差异，未表现出免疫情况。发现SD4205对该病具有抗性，在不同地点 - 年份的病害进展曲线下面积最低。其他表现出中等抗性水平的基因型包括SD4148、SD4176、“阿尔森”、SD4023、“法勒”、SD4024、“克努森”和SD4199。粒重与病害呈负相关，抽穗天数也与病害呈负相关。所鉴定出的抗性在本质上似乎是数量性状的，通过病害进展较慢和严重程度降低来表现。
