夏玉米产量与水分关系及其高效用水灌溉制度

依据灌溉试验资料，研究了水分胁迫对夏玉米生长发育和产量形成的影响，建立了产量与水分关系的数学模型，分析给出了大田夏玉米的高效用水灌溉定额，并用动态规划技术优化得出了夏玉米的最优灌水时间和每次的灌水定额。结果表明，各生育时段的水分胁迫对夏玉米的生育和产量均会造成不利影响，其中尤以抽雄～吐丝期前后４０天左右缺水对产量影响最大，其次为拔节期缺水；在１９９７年夏玉米生育期降雨量只有１３７ｍｍ的条件下，得出其最优灌溉定额为１９６６．０８ｍ３／ｈｍ２，３次灌水时间分别为７月４日、７月２８日和８月１６日。

Yield Water Relation and Irrigation Schedule of High Efficient Water Use for Summer Maize

Based on experimental data,effects of water stress on growth,development and yield formation of summer maize were studied;yield water models were established;irrigation quotas for efficient water use in summer maize were given as well as optimal irrigation scheduling were deter mined with dynamic programming technigues.The results show that water stress at various growing stages cause harmful influence on growth,development and yield of summer maize. The harmful effect of water shortage in 40 days around the tasselling stage.On condition that rainfall was 137mm during summer naize′s growing period in 1997,the optimal irrigation quota was 1966.08m 3/hm 2 and three irrigations should be conducted on 4 July,28 July and 16 August,respectively.