落花落果是温州蜜柑系统发育过程中一种自身调节的自疏现象。一株成龄温州柑树一般开花1—3万朵,但座果率只有2～5％。在生理落果期间,若遇到干旱、高温等异常天气,则会加剧落花落果,称之为异常落花落果。日本果树专家研究指出:“在2—4月花器发育期间,将普通温州蜜柑置于恒温下,在15℃时不发生落蕾落花及第一次生理落果,但在20℃时,脱落70—80％,在30℃时,则花蕾落光”。 Falling fruit is a self-regulating phenomenon in the development of Satsuma mandarin. A mature Wenzhou citrus generally flowering 1-3 million, but the fruit rate of only 2 to 5%. During the physiology fall-off period, if it encounters abnormal weather such as drought and high temperature, it will aggravate the disastrous fall, which is called abnormal drop. Japanese fruit experts pointed out that: “During the flower development in February-April, the ordinary Satsuma is placed at a constant temperature, at 15 ℃ does not occur falling and the first physical drop fruit drop, but at 20 ℃, off the 70- 80%, at 30 ℃, then the flower buds falling light. ”