Effects of Several Chemical Regulators and Their Combinations on Female Flower Number and Fruit Bearing in Chinese Chestnut

The concentration experiment and orthogonal design experiment of BR,GA3,PP333,KH2PO4 and H3BO3 were conducted by foliar spraying for flowering and fruit bearing in Chinese chestnut. The results showed that,the differences of chemical regulators,concentrations and their combinations have various impacts on the number of fruit bearing shoots per mother shoot,the length of fruit bearing shoot,the number of female inflorescence per fruit bearing shoot,the number of male flower shoots per mother shoot,weight per nut,percentage of 3 nuts per involucre and percentage of empty-shell chestnut,respectively. The optimum treatment of chemical regulation for enhancing the number of female flowers and the fruit yield,as well as for reducing the percentage of empty-shell chestnut is BR 0.01 mg·L-1 +PP333 1 000 mg·L-1 +KH2PO4 7 500 mg·L-1 +H3BO3 5 000 mg·L-1 according to the results obtained by chemical regulating experiments,which can raise the number of fruit bearing shoots per mother shoot from 1.2 to 2.833,enhance the number of female inforescence per fruit bearing shoot from 1.567 to 1.8 and drop the average percentage of empty-shell chestnut from 30.70% to 9.03%.