不同冻水和起身水组配下的冬小麦物质积累与分配

Dry Matter Accumulation and Distribution in Winter Wheat Under Different Combinations of Overwintering and Jointing Irrigations (O J Irrigations)

研究表明,随着冻、起总水量的增加或减少,小麦单株干物质积累量呈明显增加或减少趋势。叶片随着冻、起总水量的降低,在孕穗期前,向茎秆的物质转移比例增大,孕穗期后,其自身干物质积累比例下降幅度越大,相应地向穗部的物质转移比例也越大;当处理总水量超过900 m3/hm2 时,叶鞘干物质积累比例在春5 叶时最大,而不足900 m3/hm2 时则在春4 叶时最大;茎和穗子的干物质积累比例始终保持上升趋势。不同冻、起水组配对小麦不同器官可溶性糖含量具有明显的影响。冻、起总水量在600 m3/hm2 以上的条件下茎秆可溶性糖含量变化有2 个明显的高峰期:一个是春5 叶期;另一个是子粒形成期。在子粒形成期以前,茎秆可溶性糖含量随着冻、起总水量的减少而呈上升趋势;但在子粒形成期后,茎秆可溶性糖含量随着冻、起总水量的减少而呈明显的下降趋势。叶片可溶性糖含量在开花前呈明显上升趋势;而开花后,叶片中大部分光合产物转移到穗部,使可溶性糖表现下降趋势。叶鞘可溶性糖含量的变化规律与叶片相似。子粒可溶性糖含量从半仁期至子粒形成期呈明显上升趋势,子粒形成期以后则明显降低,而淀粉含量明显增高。

The studies showed that dry matter accumulation in wheat plants changed with the amount of O J irrigations.The translocation of dry matter from leaves to stems tended to increase before the bearing period,while the translocation of dry matter from leaves to spikes tended to increase after that period.Dry matter accumulation in sheathes reached maximum either in the 5th spring leaf period when the amount of O J irrigations was above 900 m 3/ha,or in the 4th spring leaf period when this amount was below 900 m 3/ha.Dry matter accumulation in stems and spikes tended to increase throughout the life cycle. The different combinations of O J irrigations had a remarkable effect on the soluble sugar content in different wheat organs.The soluble sugar content in stems,when the amount of O J irrigations was higher than 600 m 3/ha, had two peak periods,one being the 5th spring leaf period and the other being the kernels formation period.That of stems increased with the decrease of the amount of O J irrigations before the period of kernels formation.That of leaves increased before bloom and decreased after that,while most of photosynthate in leaves was translocated into spikes,sheathes were found similar to leaves in the translocation of soluble sugars.That of kernels increased before the kernels formation period and decreased afterwards.The starch content of kernels obviously increased after the kernels formation period.