土壤干旱对冬小麦生理特性和干物质积累的影响

Effect of soil drought on physiological characteristics and dry matter accumulation in winter wheat

试验用盆栽和防雨池栽 2种方法研究了不同土壤水分对小麦生长发育和产量的影响。结果表明 ,小麦生育中后期随着土壤干旱程度的加剧和干旱时间的延长 ,小麦叶片的光合强度、冠层蒸腾强度降低 ,生长明显受到抑制 ,导致籽粒产量减少。起身期改善土壤水分状况 ,显著地增加植株和各器官的干物质含量 ,延缓了绿叶干重的急剧降低。穗脖长 (穗基部与旗叶鞘顶部之间的距离 )、穗粒数、绿叶干重、植株生长速率对土壤水分反应较敏感 ,可作为小麦对土壤水分亏缺的较好指标。在旱地小麦生产和节水灌溉实践中 ,小麦生育中后期确定灌水时期应前瞻后顾。旱情严重时 ,起身期灌水好于孕穗期。

Experiments on the response of winter wheat(Triticum aestivum L.)to different soil moisture conditions were carried out in pot and in rainfall-proof trough.With the development of soil drought,photosynthetic rate of leaves of winter wheat and canopy transpiration rate decreased,and growth was inhibited significantly,result in reduction of grain yield deeply.Irrigated in starting stage for 60mm amount,the dry matter contents increased,so did dry matter contents of green leaves.Soil moisture conditions had significant effect on number of grains,green leaves dry matter contents,growth rate of plant and ear-necked-length(length from the bottom of ear to the top of flag leaf sheath).They could be better recognised as water saving irrigation idex.Under soil drought conditions in field,the opimal period of irrigation is either starting stage or booting stage,should be analyzised,according to tolal status,such as wheat field,former management and growth of winter wheat. [WT5HZ]