primary infection source

常见例句

The primary source of infection was the oospore overwintered in soil and plant survival.
其主要侵染來源是土壤中和植物病殘躰上越鼕的卵孢子。
Primary infection source may be reduced by breeding and selecting the variety with the lower infected seedling rate of seed-borne SMV.
可以通過選育和篩選種傳病苗率低的品種推廣，減少本病的初次侵染來源。
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.
一般認爲厚垣孢子是稻曲病主要的初侵染源，在水稻開花前後從穗部進行侵染；
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