Abstract: In order to explore the tolerance of Puccinellia distans to different water gradients and the optimum water supply for growth. According to the maximum field capacity (Field water content),Puccinellia distans in this experiment was irrigated in the whole growth period in greenhouse by six different water gradients,which were W₅₀ (50%FWC),W₆₀ (60%FWC),W₇₀ (70%FWC),W₈₀ (80%FWC),W₉₀ (90%FWC),and W₁₀₀ (100%FWC).The effects of different water gradient treatments on various agronomic characters of Puccinellia distans were observed. The results showed that， many indexes such as plant height,tiller,leaf length,leaf width,leaf area,chlorophyll content,fresh weight,dry weight and root dry weight were increased at first and then decreased with the increase of water content. As a whole,the maximum value was obtained under W₈₀ treatment,but there was no significant difference between W₈₀ treatment and W₇₀ treatment. Puccinellia distans had a large demand for water in the growing period,and it maintained normal growth with poor yield under the high water content of W₉₀ and W₁₀₀,but did not grow and develop normally under W₅₀ long-term treatment. In this experiment,it found that W₇₀ and W₈₀ were the best water supply gradients for the growth of Puccinellia distans. To a certain extent,Puccinellia distans grew poorly under the low water content,but had a high tolerance for the high water content in their whole growth period.

Key words: Puccinellia distans, Different water gradients, Growth and development, Agronomic character

摘要： 为了探究碱茅（Puccinellia distans）对不同水分的耐受能力及生长最适的供水量，本试验通过温室盆栽方法对碱茅进行全生育期灌溉，按照土壤田间最大持水量（Field water content，FWC）共设定6个不同水分梯度，分别为W₅₀（50% FWC），W₆₀（60% FWC），W₇₀（70% FWC），W₈₀（80% FWC），W₉₀（90% FWC），W₁₀₀（100% FWC），观察不同水分梯度处理对碱茅多种农艺性状的影响。结果表明：碱茅的株高、分蘖、叶长、叶宽、叶面积、叶绿素含量、鲜重、干重和根干重等均随着水分含量增加而呈现先增加后减少的趋势，整体在W₈₀处理下获得最大值，但多种指标与W₇₀处理差异不显著；碱茅生长期对水分需求较大，在W₉₀和W₁₀₀处理下仍能维持生长但产量较差，而在W₅₀长期处理下无法正常生长发育。综上所述：W₇₀至W₈₀处理为碱茅长势最好的水分处理梯度，整个生育期中水分过低条件下碱茅长势较差，但对水分较高时具有一定耐受性。

关键词: 碱茅, 水分梯度, 生长发育, 农艺性状