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。

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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。

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The main source of primary infection comes from hypha, akinetes and sclerotiums over-wintering in the bulb, residues of diseased plants and the soil.

病菌以菌丝体在种球内，或以菌丝体、厚垣袍子及菌核随病残体在土壤中越冬，成为翌年的主要初侵染源。

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