primary infection source

常见例句

The primary source of infection was the oospore overwintered in soil and plant survival.
其主要侵染来源是土壤中和植物病残体上越冬的卵孢子。
Primary infection source may be reduced by breeding and selecting the variety with the lower infected seedling rate of seed-borne SMV.
可以通过选育和筛选种传病苗率低的品种推广，减少本病的初次侵染来源。
It is presumed that chlamydospore may be the major primary infection source of rice false smut and begin to infect the panicles of rice before or after florescence.
一般认为厚垣孢子是稻曲病主要的初侵染源，在水稻开花前后从穗部进行侵染；
http://dict.cnki.net