马铃薯Y病毒的侵染与温度的关系

 在北京,对于秋播的马铃薯接种Y病毒并不显著增加感染率和花叶型退化程度。在春播的条件下无病毒的实生苗后代植株一季内大多数自然感染Y病毒。
盆栽试验证明降低夜间气温和土温、降低昼夜土温或仅降低夜间土温都有效地降低了春播马铃薯在自然和人工接种条件下Y病毒感染率。接种后1、3、5星期的检验结果表示,降低土温大大延缓了叶片内Y病毒的发展。因此推想,低温除了其他有利作用之外,会增强马铃薯对于Y病毒的抗扩展免疫性。

EFFECT OF TEMPERATURE ON Y VIRUS INFECTION IN POTATO PLANTS

In Peking,inoculation of autumn-sown field plants of potatoes with Y virus did not significantly increase the percentage of Y virus infection in the harvested tubers.Under spring-sown conditions,however,most of the virus-free plants derived from seedlings became naturally infected with Y virus within one season.
Experiments with potted plants demonstrated that lowering of night air and soil tempera-ture,of day and night soil temperature,or of only night soil temperature effectively checked Y virus infection in the spring-sown potato crop,either artificially inoculated or exposed to natural infection.Assay made one,three,and five weeks after inoculation showed that lower-ing of soil temperature greatly retarded the development of Y virus in potato leaves.