Leaf blotch of wheat caused by Bipolaris sorokiniana is a major constraint to wheat production, causing significant yield reduction resulting in severe economic impact. The present study characterizes to determine and compare pathogenic variability exist/not based on components of leaf blotch disease development and level of aggressiveness due to agroclimatic condition of B. sorokiniana in wheat. A total of 169 virulent isolates of B. sorokiniana isolated from spot blotch infected leaf from different wheat growing agroclimate of Bangladesh. Pathogenic variability was investigated on a susceptible wheat variety 'kanchan' now in Bangladesh. A clear evidence of positive relationship among the components was recorded. From hierarchical cluster analysis five groups were originating among the isolates. It resolved that a large amount of pathogenic diversity exists in Bipolaris sorokiniana. Variation in aggressiveness was found among the isolates from different wheat growing areas. Most virulent isolates BS 24 and BS 33 belonging to High Ganges River Flood Plain agro-climatic zones considered by rice-wheat cropping pattern, hot and humid weather, high land and low organic matter content in soil. Positive relationship was found between pathogenic variability and aggressiveness with agro-climatic condition.

中文翻译：

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基于小麦叶斑病发展成分和农业气候起源的病原变异评价。


小麦叶斑病是小麦生产的主要制约因素，造成小麦产量大幅减产，造成严重的经济影响。本研究的特点是根据叶斑病发展的组成部分以及由于小麦中B. sorokiniana的农业气候条件而导致的侵袭性水平来确定和比较是否存在致病变异。从孟加拉国不同小麦生长农业气候的斑枯病感染叶子中分离出总共 169 株B. sorokiniana强毒菌株。对孟加拉国的易感小麦品种“kanchan”的致病变异进行了研究。记录了各成分之间正相关关系的明确证据。根据层次聚类分析，五个组源自分离株。解决了Bipolaris sorokiniana存在大量的致病多样性。来自不同小麦产区的分离株的攻击性存在差异。从稻麦种植模式、气候湿热、土地高、土壤有机质含量低的角度考虑，最强毒力菌株BS 24和BS 33属于高恒河漫滩农业气候区。致病变异性和侵袭性与农业气候条件之间存在正相关关系。