陇东南地区玉米分期播种试验及适时播种期探讨

目的]探究播种期对气候资源利用及玉米产量的影响,研究气候变暖对玉米适宜播种期的影响。方法]通过分期播种试验确定陇东南地区玉米适宜播种日期。结果]早播玉米与迟播玉米虽然在播种～出苗期、七叶期～拔节期及乳熟期～成熟期间的间隔天数及≥10℃积温差异较大,但全生育期天数及总积温差异较小;早播玉米部分生育期间隔时间增长,迟播玉米播种～出苗期间隔时间缩短;全生育期生物累积量随≥10℃的积温呈线性变化,各播期玉米生物量在拔节前差异较小,拔节后平均播种期玉米生物量增加高于其余各播期玉米;平均播种期是比较适宜的播种期,玉米成熟期果生物量累积也高于其他播期。结论]该研究可为充分利用气候资源提供依据。

Experiment in the Timely Sowing of Maize in Southeastern Gansu and the Analysis of its Suitable Sowing Period

Objective] The effect of sowing date on the utilization of climate resource and maize yield,and the variation of warming climate affecting the suitable maize sowing were studied. Method] The suitable sowing date of maize in Southeastern Gansu was determined through the experiment in its timely sowing. Results] Total number of day and the accumulated temperature of whole growth period was with little difference even though there was a quite difference in the interval of days from the sowing to emergence,from the period of seven leaves to jointing stage,from the milky stage to mature stage and the accumulated temperature of ≥ 10 ℃ between the early seeding and later sowing of maize. The interval time of the partial period of maize growth and development in early seeding was increased and the interval time from the maize was shortened. There was a linear change in accumulation of the biomass of whole maize growth period with the variation of the accumulated temperature of ≥ 10 ℃. The difference in the maize biomass before its jointing stage in various sowing dates was less and the increment of the maize biomass after its jointing stage in average sowing date was higher than these of the other sowing dates. The average sowing date was more appropriate sowing time,in which the biomass accumulation of maize seed in mature stage was also higher than tease of other sowing dates. Conclusion] The reference for the full use of climatic resources was provided through the experiment.