Abstract:

Abstract: The effects of air relative humidity (RH) on the flowering and fruit-set of tomato under high temperature were investigated in growth chambers. Two air relative humidity treatments from 10:00 to 16:00 were 70% ± 5% (high RH) and non-humidification (low RH, as control). The results showed under the high temperature (the average temperature from 10:00 to 16:00 was 36.5 ℃), inadequate carbohydrate and burned flower buds in 55% RH (low RH) increased rate of flower buds drop and lead eventually low fruit set. However, when the air humidity reached 70%, rate of flower blooming and fruit set was improved by 27%~34% and 26%~30%, respectively, which resulted from enhanced carbohydrate supply and decreased burned-flower buds. As a conclusion, relative humidity of 70% (high RH) was fit for flowering and fruit-set of tomato under high temperature of 36.5 ℃.