摘要
系统研究了毛乌素沙地主要粮食作物糜子在自然和水分胁迫条件下生理、生态特性的日变化和季节变化特征。结果表明 :(1)由于滩地小环境因子的特殊性 ,使拔节期滩地糜子的光合速率高于盆栽对照。 (2 )土壤水分胁迫主要在抽穗期至灌浆期造成植物体内较大的水分亏缺 ,在拔节期亏缺不明显。 (3)水分胁迫使糜子各生长季的光合速率下降 ,其中轻度胁迫降低了 9%～ 2 3% ,严重胁迫降低了 30 %～ 5 0 %。 (4 )轻度水分胁迫有利于气孔的张开 ,从而使蒸腾速率略高 ,但“午休”现象减缓。 (5 )水分胁迫使糜子各生长季叶面积指数降低 ,其中轻度胁迫降低了 7%～ 12 % ,严重胁迫降低了 2 1%～2 9%。
The diurrnal variations of the physi ological and ecological characteristics of Panicum miliaceum L., a primary c rop in Mo Us Sandy land, in response to their natural environments and water stress were studied b y using Li 6200 photosynthesis measurement system. The results showed: (1)The p hotosynthesis rate (P n)of the P.miliaceum L. at elongation stage in the i nterdu nes was increased by the special local environmental factors. (2) Plants experie nced more insufficient water availability at heading and filling stages rather t han elongation stage due to soil water stress. (3) Water stress led to decreased photosynthesis rate of P.miliaceum L., slight water stress made the photosy nth esis rate decreased by 9%～23%, while severe stress made it decreased by 30%～50 %. (4) Slight stress favourable for stomatal stretch increased transpiration rat e but weakened 'noon break'. (5) Water stress decreased the leaf area index a t different stages, slightly stressed decreasing by 7%～12% while severely stre ssed decreasing by 21%～29%.
出处
《作物学报》
CAS
CSCD
北大核心
2001年第6期908-914,共7页
Acta Agronomica Sinica
基金
中国科学院寒区旱区环境与工程研究所知识创新前沿 (2 10 0 31号 )课题
国家自然科学基金重大项目 (93890 2 9号 )课题资助
关键词
毛乌素沙地
糜子
生理生态特性
水分胁迫
Mo Us Sandy Land
P.miliaceum L.
Physi ological and ecological characteristics
