Effect of calcium fertilizer on the fruit yield and quality of Chuntian tangerine.

[Objective]In order to provide scientific basis for using calcium fertilizer in Chuntian tangerines, the present study was conducted to examine the effect of different calcium fertilizers on fruit cracking, fruit yield, and fruit quality of Chuntian tangerine. [Method]Five experimental treatments were set: treatment 1: no fertilization treatment as control; treatment 2: calcium acetate application treatment; treatment 3: calcium nitrate application treatment; treatment 4: calcium biphosphate application treatment; treatment 5: liming application. The calcium acetate, calcium nitrate, and calcium biphosphate fertilizers were applied by foliar spraying, while the liming application was applied by soil application. The foliar spaying fertilizer was designed according to the same amount of calcium. The liming application rate was 1.5 kg/plant, and the appropriate application time was during early fruit enlargement stage. During the fruit cracking peaking period, the fruit cracking situation was investigated; then, during the fruit maturity period, the fruit yield was determined and the fruit quality was analyzed. [Result]Compare with the results of the control, using calcium fertilizers could obviously reduce the number of cracked fruits and increase the fruit weight and yield. The fruit yield increase rate was arranged in the following descending order: limecalcium acetatecalcium dihydrogen phosphatecalcium nitrate, with the increase rate of each fertilizer at 22.43%, 18.75%, 15.09%, and 13.24%, respectively. By applying calcium fertilizer, the fruit acidity reduced, the fruit sugar acid ratio increased by 125.0%-186.5%, the calcium and vitamin C content in the fruit peel improved, and the rotten fruit rate during storage period reduced all at the same time. [Conclusion]Calcium fertilizer application had significant effect on the yield and quality of tangerine fruit; not only could the fertilizer improve the fruit yield, but it could also improve the fruit quality.