敦煌气候条件及对棉花产量因素的影响

甘肃敦煌地区气候条件虽然适宜棉花生长,但热量条件处于棉花正常生长适宜指标的下线,对棉花的产量和质量具有较大影响。利用敦煌市国家基准气象观测站1983~2012年农业气象观测资料,统计分析了敦煌棉花全生育期气象条件对棉花的株铃数、单铃重及僵烂铃率、蕾铃脱落率及产量的影响。结果表明：棉花花蕾期气温、花后热量和花期气温、裂铃吐絮阶段灌水量是造成棉花僵烂铃和蕾铃脱落的主要原因。花铃期的平均气温越高,热量越充足,越有利于棉铃数的增加;7月上旬至8月中旬夜温不足降低了棉株矿物质和贮存物的积累速率,导致花蕾及胚珠发育不良,单铃胚珠数减少;盛夏7月中旬高温造成棉铃代谢紊乱,导致单铃不孕,造成株铃数不足和单铃重下降,进而影响棉花产量。

Climate Characteristics and Its Influence on Cotton Yield in Dunhuang of Gansu Province

Though the climatic conditions of Dunhuang in Gansu Province are suitable for cotton growing,the heat is in the lower value of cotton normal growth,and it greatly affects on yield and quality of cotton in Dunhuang. This article analyzed the influence of meterological conditions on cotton bolls number,single boll weight,rotting rate,dropping rate and yield of cotton during the whole growth period using the observation data of Dunhuang agricultural meterological station from 1983 to 2012. Results are as follows： The temperature at the budding and flowering stages,the heat at the late flowering stage and irrigation amount at boll opening stage played important roles to the boll rotting and dropping. The higher average temperature and more heat at flowering and boll setting stages of cotton would be more beneficial to increase the quantity of bolls. From early July to middle August,the insufficient temperature at night reduced the accumulation rate of mineral and storage of cotton plant,which would lead to poorly developed flower buds and ovules,and then the quantity of ovules for single boll decreased. The high temperature in middle July can be easy to cause metabolic disturbance of cotton bolls,bring about sterility of single boll and make the quantity of bolls insufficiency and the weight decrease,and finally result in a decrease of yield.