荔枝龙眼在果实发育过程中，有三个集中的落果期：①花期落果。主要原因是授粉受精不良和第二批雄花大量开放与幼果争夺养分剧烈，造成幼果胚败青。②幼果期落果，特别是果肉包至种子1／3－2／3时，落果最多。主要原因是营养供应不足和虫害（蝽蟓）。③采果前落果。主要原因是 Litchi longan in the fruit development process, there are three concentrated deciduous period: flowering fruit drop. The main reason is poor pollination and fertility and the second batch of male flowers open to a large number of violent competition for young nutrients, resulting in young fruit embryos. ② fruit drop fruit, especially fruit bag to the seed 1 / 3-2 / 3, the most fruit drop. The main reason is the lack of nutrition and pests (bugs). ③ fruit before falling fruit. The main reason is