播种期对农牧交错带马铃薯生长发育和产量形成及水分利用效率的影响

摘要

为了研究不同播种期对农牧交错带马铃薯生长发育和产量形成以及水分利用效率的影响,为农牧交错带马铃薯适期播种和高产栽培提供科学依据,采用随机区组排列设计,分析了超早播(4月28日)、早播(5月8日)、中播(5月18日)、晓播(5月28日)和超晚播(6月8日)五个播期下马铃薯生育期、形态指标、产量形成和水分利用效率的变化情况.结果表明:播种期对马铃薯生育期、株高和叶面积指数影响显著.随播期推迟,马铃薯生育期缩短,播期每推迟10 d,生育期平均缩短6d,而生殖生长期在总生长期中的比例增加,超早播和超晚播处理下分别为45％和59％.超早播和早播马铃薯地上部干物质积累显著低于其余播期,不同播期处理薯块鲜重增长符合Logistic生长曲线,播期间马铃薯总产量、大薯产量和大薯率差异均达显著水平,其中中播、晚播和超晚播产量差异不显著,平均达21 593 kg/hm2,超早播和早播产量平均为15 181 kg/hm2.马铃薯水分利用效率随播期推迟增加,超早播为45.2 kg/( hm2·mm),超晚播为86.3 kg/(hm2·mm).建议农牧交错带马铃薯适宜播种期安排在5月中下旬.%In order to study the effects of different sowing dates on the growth, development, yield formation and water use efficiency (WUE) of potato and provide a scientific basis for optimal sowing date and high yield of potato in A-gro-pastoral Ecotone, phenology, morphological index, yield formation and WUE of potato under five sowing-date treatments of SE( April 28) , E(May 8) , M(May 18), L(May 28) and SL(June 8) were compared using randomized block design based on a field experiment in WuChuan county. The results showed that phenology, plant height and leaf area index (LAI) were significantly different under different sowing dates. The growing period of potato was shortened at a rate of 6 days averagely with the sowing date postponed by 10 days, whilst the ratio of the reproductive stage in growing period was increased, which reached 45 % and 59 % respectively under SE and SL treatments. Aboveground dry matter accumulation under SE and E treatments were significantly lower than that of other sowing dates. In the whole period, the fresh tuber weight increased as the Logistic growth curve. Total yield and yield of big potato as well as the number of big potatoes in all were significantly different. The difference of yield between M, L and SL treatments was not significant and their averaged yield reached 21 593 kg/hm2, while there were also no significant difference in yield between SE and E treatments, reached 15 181 kg/hm2 averagely. WUE increased as the sowing date delayed. The highest value and the lowest value of WUE occurred under SE and SL treatments, which were 45.2 kg/(hm2"mm) and 86.3 kg/(hm2-mm) respectively. The appropriate sowing date of potato in Agro-pastoral Ecotone was recommended to be arranged in middle-late May.