Low temperature during seedling stage promotes female flower determination but not yield of Chieh-qua

摘要

Temperature has an important effect on plant growth and sex determination in flowers. The effect of different temperatures (high temperature: 30°C /25°C (dayight), medium temperature: 25°C /18°C and low temperature: 15°C /10°C ) on flower sex determination and fruit yield was studied in Chieh-qua (Benincasa hispida Cogn. var. Chieh-qua How. ‘No. 4 Jiang xin’), also the content of absicsic acid (ABA) and indole acetic acid (IAA) in the shoot apex was measured. The results showed that medium and low temperatures during seedling stage boost the female flower differentiation after transplanting, compared with high temperature treatment, and the effect was more obvious when the temperature was lower. Lower temperature increased the content of ABA and IAA in shoot apex of Chieh-qua. There was a positive relationship between the ratio of IAA/ABA and plant female flower determination under different temperature treatments (R2 = 0.8744). Temperature may affect female flower differentiation of Chieh-qua by changing the contents of ABA and IAA in shoot apex. Fruit yield was not significantly affected by different temperature treatments.