病害发生与牡丹不同品种、初侵染源等因子密切相关。
The occurrence of disease was closely correlated to the initial infection sources and species of peony tree.
富含胆碱的残留花药、雌蕊及早期颖果是禾谷镰孢菌的主要初侵染源；
Besides anthers at anthesis, pistils and young caryopses are rich in choline and are the main sites of the initial infection.
研究发现，病害的初侵染源来自枝干病斑，生长季节枝、叶、果互相交叉传染。
The study shows that the initial infection source of the disease is the disease spot on the branches. In the growing season branches, leaves and fruits can infect one another.
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。
The main source of primary infection comes from hypha, akinetes and sclerotiums over-wintering in the bulb, residues of diseased plants and the soil.
炼苗期烟草苗床是传毒介体有翅蚜着落的靶子中心，是烟田蚜传病毒病的主要初侵染源，为防治烟草蚜传病毒病的关键时期。
During the tobacco hardening period bed of tobacco seedling was the falling target of alate aphids and was the main resource of tobacco virus spread by aphids.
炼苗期烟草苗床是传毒介体有翅蚜着落的靶子中心，是烟田蚜传病毒病的主要初侵染源，为防治烟草蚜传病毒病的关键时期。
During the tobacco hardening period bed of tobacco seedling was the falling target of alate aphids and was the main resource of tobacco virus spread by aphids.
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