不同保果方式和气象因子对鲍威尔脐橙冬季落果的影响

Effects of Different Fruit Drop Prevention Measures and Climate Factors on Winter Fruit Drop of Powell Navel Orange

调查了鲍威尔脐橙在重庆市奉节铁佛果园和巫山县福田果园两个点的冬季落果情况。结果表明,自然情况下,奉节铁佛果园的鲍威尔脐橙落果率明显低于巫山福田果园的落果率,至翌年2月底,后者的落果率是前者的5倍左右;和对照相比,11月和12月上旬喷两次保果剂处理能够明显降低脐橙的落果率。结合两个点的不同生态气候条件,对落果的原因进行了分析,认为低温特别是-2℃温度持续时间的长短是影响落果的主要原因。

Fruit drop rates of Powell navel orange trees treated with or without fruit drop prevention chemicals（2,4-D＋fungicide＋miticide＋fertilizers） during winter were surveyed in Fengjie Tiefu orchard and Wushan Futian orchard.The results showed that the fruit drop rate in Fengjie Tiefu orchard was apparently lower than that in Wushan Futian orchard under natural conditions.In the end of February,5-times more fruit dropped in Wushan Futian orchard than in Fengjie Tiefu orchard.When compared with control,two applications of fruit drop prevention chemicals in November and early December significantly reduced fruit drop.Analysis showed that the duration of low temperature,especially the number of days under-2 ℃,was the main factor influencing winter fruit drop.