中文摘要：

在茶园设置塑料大棚双层覆膜、3层覆膜、3层膜并电热线加温等3个处理，以露地栽培为对照，比较了茶园小气候、茶树生长、光合特性、茶叶内含成分及产量的差异。结果表明：不同层次覆盖明显提高了茶园日平均气温、地温和相对湿度，虽光照降低，但晴天茶树净光合速率是对照的2．46～2．84倍；茶叶新梢长度、百芽质量和芽密度均显著增加，1芽1叶茶芽采摘期比对照提前10～21d；3种处理茶鲜叶产量分别提高80％、96％、176％。生化分析结果显示，各处理茶多酚、氨基酸、咖啡碱和水浸出物均有显著差异，双层覆膜处理的茶叶酚氨比达到高档绿茶标准。

英文摘要：

This article aimed to determine the effect of different levels of coverage on microclimate, growth and quality of tea. The temperature, humidity, illumination of tea garden and photosynthetic characteristics, ingredients and yield of tea were measured. Four different treatments, i.e., outdoor cultivation （CK）, double-film covering, triple-film covering and triple-film covering with electricity heating were included. The results showed that different level cover obviously en-hanced the average temperature, ground temperature and relative humidity within the tea garden. Furthermore, the net photosynthetic rate of treatments in the sunny day was 2.46-2.84 times than that of CK. However, the intensity of illumi-nation in the greenhouse decreased. In addition, the new shoots, hundred buds weight and budding density of tea also in-creased significantly. Therefore, the picking time of one-bud and one-leaf of treatments was 10-21 d earlier than that of CK, and the tea fresh leaf yield of three treatments increased by 80%, 96%, 176%, respectively. Biochemical analysis indicated that contents of tea polyphenol, amino acid, caffeine and water extracts of each treatment were significantly dif-ferent. The tea phenol ammonia ratio of double-film covering reached fine-grade green-tea standards.