海南冬季棉花生育期分析

采用124个陆地棉品种(系),于2004-2005年冬季在海南岛三亚进行了4个播期的自然生育期试验。结果显示,全生育期平均为132.75 d,与我国主产棉区相差不大。不同播期之间全生育期相差较明显,以10月1-2日的第一播期最短,11月16-20日的第三播期最长,两者相差约15 d。冬繁棉花,早熟与中熟品种的全生育期相差不大(不到5 d),与棉区差异悬殊。就是在12月初播种,两个熟性的品种在4月中旬都能够完成自然生育期。根据试验结果,作者提出了冬繁棉花的“凹型生长模式”,并发现在后期播种的各个生育阶段,生育期的调节存在“缓冲”或“补偿”作用。根据凹型模式,作者提出科研南繁和产业南繁最佳播种期是10月,而抢季南繁在12月初播种亦可成功,并认为控制生育期的关键是在生长速度“低谷”时期。

Analyses on Growth Stages of Winter-season Cotton in Hainan Island

Natural growth stages of four planting procedures for 124 cotton accessions(Gossypium hirsutum) were investigated in Hainan Island in winter of 2004 and 2005.The whole growth stages from planting to boll opening averaged with 132.75 days,which was not much different from those in cotton production belts in China(Mainland).It was evident that there was difference between whole growth stages among four planting procedures with the shortest of first planting procedure(October 1 to 2) and the longest of third planting procedure(November 16 to 20).Nearly 15 days differed from those two planting treatments.Whole growth stages of two types of cotton varieties with short and long seasons behaved remarkablely different in their original belts,but did not show any big difference(not over 5 days) in winter-season in Hainan Island.Both types of cotton varieties could mature naturally in mid April,even if planted in early December.Authors of this paper suggested,based on the experimental results,an U-growing pattern for winter-season cotton and a self-complementing mechanism may exist between cotton from the latest two planting procedures.According to the U-growing pattern,the authors pointed out that the reasonable planting dates should be in October for winter-season cotton aimed at both scientific research and industrialization,but it would be also okay to plant cotton in early December if it might be hurry to plant for saving seasons.It was critical to control cotton development during mid or little later growing season for the limited growth period.