大豆花叶病毒株系间的交叉保护作用研究

利用11个来源不同的大豆花叶病毒株系在不同大豆品种上研究了接种间隔以及混合接种等处理方法对交叉保护效果的影响；研究了不同类型保护处理组合之间保护效果的差异，并观察了交叉保护作用对大豆部分农艺性状的影响。结果显示，不同挑战接种时间交叉保护作用存在明显差异，与保护接种间隔7d挑战接种保护效果显著好于间隔3、5、9、11d；接种处理方法不同，交叉保护效果也不同，先后接种两个株系可表现保护作用，两株系汁液等体积混合接种或同时各接种一片真叶则不表现保护作用；以同一品种上不同症状类型的SMV株系作为保护株系其保护效果存在程度差异，以花叶株系作为保护株系，表现较高的保护作用，以坏死株系作为保护株系，不表现保护作用。交叉保护作用能够显著减轻挑战株系对叶面积和根干重的影响。交叉保护作用在减轻SMV对株高、叶绿素含量和根瘤鲜重的影响上，不同株系、不同品种间存在一定差异。

Cross protection effects between strains of soybean mosaic virus

Eleven strains of soybean mosaic virus （SMV） from different regions were used to study effects on cross protection by different challenge time and inoculation treatments, to compare difference of the cross protection between strains, and to analyze effects of cross protection on some characteristics of soybean cultivar. The results showed that different challenge inoculation time after protection inoculation clearly affected cross protection. Protection rate was higher in seven days than that in three, five, nine and eleven days. Cross protection was also affected by different inoculation treatments. Cross protection was observed when cultivars inoculated by one strain after another, whereas no protection appeared when cultivars were inoculated with mixture of two strains, or each unifoliolate was inoculated by different strains respectively. Cross protection varied in degree when strains with different symptom were used as protection inoculums. Mosaic strain exhibited much better protection effect than necrosis strain. Cross protection decreased effect of SMV on leaf area and root dry weight. The effects of cross protection on plant height, chlorophyll content and nodule fresh weight depended on different soybean cultivars and SMV strains.