棉铃发育与气候的探讨

综合几年对棉铃发育与气候条件的系统研究结果,初步明确了棉铃有关经济性状的具体热量指标:≥15℃活动积温值1500～1500度-日为棉铃正常吐絮的积温指标,棉铃正常吐絮不得少于1100度-日,铃期与铃期内日平均气温呈高度负相关(r=—O.9087)。15℃为棉铃能否正常吐絮的最低临界温度,单铃籽棉率与50日龄内≥18℃的天数及其积温值相关显著,35天和800度-日为单铃籽棉率的最低临界指标,平均气温低于20℃,成熟棉籽不足30％,纤维品质优劣与花期早迟及水、热、光等气候条件密切相关。安阳棉花有效开花的终止期为8月20日,要使棉花优质高产,必须以伏桃为主体,力争早秋桃,尽量减少秋桃在三桃中的比例。

A STUDY ON THE COTTON BOLL DEVELOPMENT WITH THE CLIMATIC CONDITIONS

A comprehensive study on the system between the boll development and the climatic conditions for seyeral years show that a preliminary result of the specific heat unit index relative to economic characteristics of the cotton bolls has been obtained. The active accumulated temperature≥15℃ between 1,300—1,500 degree-day is the accumulated temperature index for boll opening under normal conditions. The accumulated temperature for boll opening under normal conditions should be not less than 1,100 degree-day. There is a highly negative correlation between boll setting period and the average daily temperature within the boll setting period with r=-0.9087. The lowest critical temperature for boll opening unclef normal conditions is at 15℃. There is a significant correlation between seed cotton percentage/boll ard the days≥18℃ within the 50 days boll development and the accumulated temperature durirg this period. The lowest critical index for the seed cotton percentage/boll is in 35 days and 800 degree-day. Under the conditions with the average temperature less that 20℃, the percent of matured seeds is no morethan 30％. The fiber quality is closely correlated with the early or late advent of the flowering period and with the water, heat unit and the sunshine. The effective flowering period is Often stopped on August 20 for cottons grown in Anyang. Based on this, it must rely on the bolls set in the mid summer, obtain bolls set in early autumn as many as possible and decrease the percent of autumn bolls in the rank of mid summer bolls, early autumn bolls and autumn bolls as far as possible.