【摘要】 以54个对稻曲病抗感程度不同的3种穗型粳稻品种(系)为材料,对田间稻曲病自然发病情况进行调查,计算发病率、严重度和损失率。分析稻曲病与株高、剑叶长、剑叶角等株型性状及穗长、颈穗弯曲度、着粒密度等穗部性状的关系。结果表明,稻曲病的发生存在着显著的品种间差异,直立穗型品种的发病率最高,并且显著高于弯曲穗型和半直立穗型,弯曲穗型品种的发病率略高于半直立穗型,但二者差异未达到显著水平。稻曲病的发生与株型特点并无必然的联系,而与穗部性状有较密切的关系,相关性大小为每穗粒数>二次枝梗粒数>二次枝梗数>着粒密度>二次粒率。同时还与单位面积穗数有一定联系。每穗粒数较多,尤其是二次枝梗上粒数较多是稻曲病发病率高的根本原因,穗型的直弯并不是影响稻曲病发病率的主要原因。更多还原

【Abstract】 With 54 typical japonica resistant and susceptible cultivars as materials,including 31 erect-panicle type,13 se-mi-erect-panicle type and 10 curved-panicle type cultivars,incidence,severity and loss rate of false smut of rice(FSR) were studied from naturally infected cultivars.Plant type traits such as plant height,angle and length of flag leaf were in-vestigated.Panicle traits such as panicle length,panicle curve and grain density were also measured.The results showed that the disease incidence was obviously different among cultivars.Disease incidence of erect-panicle type rice was signifi-cant higher than that of curved-panicle type rice and semi-erect-panicle type rice,while the curved-panicle type rice was a little higher than semi-erect-panicle type rice,but there was no significant difference.There was no relationship between FSR and plant type,but FSR was closely related with panicle traits,with correlation rate in this order: gains per panicle> gains per secondary branch>numbers of secondary branch>the percent of gains per secondary branch.There was also some relation between FSR and the number of panicle per m2.The high number of gains per panicle,especially the high number of gains per secondary branch,was the fundamental reason of high disease incidence.Panicle type was not the primary rea-son of high disease incidence.更多还原