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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始态可概括为源区、源岩、库岩、矿源层和剥蚀区等，终态可以概括为矿带、矿田和矿床等多个等级体制。

The initial state can be summarized as source region, source rock, reservoir rock, source bed, a denudation area, etc.

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应用田口稳健性概念和技术，例如，信噪比、可控因素、噪声因素、对外部波动源的稳健性等。

Apply Taguchi robustness concepts and techniques such as signal-to-noise ratio, controllable and noise factors, and robustness to external sources of variability.

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