The role of silicon in preventing appressorial penetration by the rice blast fungus
The role of silicon in preventing appressorial penetration by the rice blast fungus
复制标题
DOI：
10.1094/phyto-98-9-1038
复制
发表时间：
2008-09-01
期刊：
影响因子：
3.2
通讯作者：
Ishiguro, K.
中科院分区：
文献类型：
--
作者：
Hayasaka, T.;Fujii, H.;Ishiguro, K.
为了检验硅（Si）赋予抵抗水稻稻瘟病菌附着胞渗透的假设，附着胞渗透到叶表皮形成的总附着胞的比例进行了比较，水稻植株与不同比率的硅胶修正到那些植物nonamended。幼嫩叶片中Si的量与施用到水稻植物的硅胶的量一致。通过能量色散X射线分析检测到的叶片近轴面上的相对Si水平也随着硅胶施用量的增加而增加。通过对水稻叶片近轴面的光学显微镜观察，发现随着硅胶用量的增加，水稻叶片附着胞穿透的比例逐渐降低，而随着喷雾接种后时间的延长，附着胞穿透的比例逐渐增加。因此，这些结果有力地支持了这一假设，并表明硅在叶表皮可能赋予抵抗附着胞渗透。同时，每叶病斑数也随施硅量的增加而减少，但只有部分穿透的附着胞可成为感病病斑。这表明Si还赋予在穿透后对稻瘟病感染的生理抗性。
To test the hypothesis that silicon (Si) confers resistance against appressorial penetration of the rice blast fungus, the proportion of appressorial penetration into the leaf epidermis to total appressoria formed was compared among rice plants amended with various rates of silica gel to those plants nonamended. The amounts of Si in the youngest leaves were consistent with the amounts of silica gel applied to the rice plants. Relative Si levels on the adaxial surface of leaves as detected by energy dispersive X-ray analysis also increased with the amounts of silica gel applied. Based on light microscopic observation of the adaxial surface of rice leaves, the proportion of appressorial penetration was reduced by increasing amounts of silica gel applied and increased with the length of period after spray inoculation. Consequently, these results strongly support the hypothesis and suggest that Si in the leaf epidermis may confer resistance against appressorial penetration. Meanwhile, the number of lesions per leaf also decreased with the amount of Si applied, while only a certain part of penetrated appressoria could become sporulating susceptible lesions. This suggests that Si also confers physiological resistance against blast infection after the penetration.