| Using‘Honey Crisp’apple as the test material, by spraying different calcium fertilizers and calcium fertilizer mixed application hormones (IAA and GA3) at the young fruit stage, the calcium fertilizers with better calcium supplementation and suitable hormones were screened out. The concentration provides a theoretical basis for calcium supplementation in apple production. The test site is located at Xunyi Apple Experimental Station of Northwest A&F University. In 2019, the amino acid calcium and sugar alcohol calcium were spayed separately,different concentrations of hormones (IAA and GA3) were applied simultaneously.A control was set up, sugar alcohol calcium 800 times solution, amino acid calcium 800 times solution and amino acid calcium 800 times solution were mixed with 8 treatments of 10mg/L GA3, 20mg/L GA3, 30mg/L GA3, 10mg/LIAA, 20 mg/LIAA and 30 mg/LIAA, respectively, according to the formula concentration and the combined program, was sprayed on foliage and fruit surfaces.15 days after the full blooming period.From fruit-setting (late April), spraying once every 10 days for a total of 3 times. In 2020, the effective treatments screened in 2019 would be repeated and verified, and 4 treatments would be added 800 times solution of calcium sugar alcohol mixed with 20mg/LGA3 and 20mg/LIAA, 0.5% calcium nitrate and 0.5% calcium chloride. After the fruits were harvested, the calcium content of the fruits and related indexes of fruit quality were determined. In 2019, the results showed that the sugar alcohol calcium was a kind of calcium fertilizer with better calcium supplement effect. The calcium content of fruits treated with 800 times solution of sugar alcohol calcium was 200% higher than that of CK. In the treatment of mixed application of amino acid calcium and hormone, the calcium content of apple fruit treated with 800 times solution of amino acid calcium mixed with 20mg/L GA3, 20mg/LIAA and 30mg/LIAA was significantly higher than that of the control and other combined hormone treatments. In 2019, different treatments increased the single fruit weight of ‘Honey Crisp’ fruit to varying degrees. The content of sorbitol in different treatments was significantly lower than that of CK, and there was no significant difference between different treatments. In the treatment in 2020, the calcium supplement effect of the sugar alcohol calcium 800 times liquid and the sugar alcohol calcium 800 times liquid was mixed with 20 mg/L GA3and 20mg/LIAA, respectively, and the calcium content increased by 95%, 126%, and 121, respectively relative to CK. Compared with CK, the calcium content of fruits treated with 800 times of amino acid calcium solution mixed with 20mg/LGA3 and 20mg/L IAA increased by 30% and 72%, respectively. Compared with CK, the calcium content of 0.5% calcium nitrate and 0.5% calcium chloride treatment increased by 45% and 35%. Except for the 0.5% calcium chloride treatment, the other treatments significantly increased the single fruit weight of the‘Honey Crisp’ fruit. In 2020, different treatments significantly improved the hardness of the fruit skin, and the extensibility of the fruit skin was significantly improved compared with CK. The content of sorbitol in different treatments was significantly lower than that of CK, which was consistent with the treatment in 2019.In this experiment, after spraying of the different calcium fertilizers and hormone treatments at the young fruit stage,it is found that sugar alcohol calcium is a kind of calcium fertilizer with a better calcium supplement, and the mixed application of calcium fertilizers 20mg/LIAA and GA3 can significantly improve the calcium supplementation effect, and the treatment of different calcium fertilizers and the mixed application of calcium fertilizers can increase the single fruit weight of the‘Honeycrisp’ fruit to varying degrees. The sugar-acid ratio of the fruit is increased by the 800-fold solution of sugar alcohol calcium, and the color of the fruit is increased. With different treatments, the hardness and ductility of the peel are significantly improved, the content of sorbitol is significantly reduced, and the quality of the fruit is improved to a certain extent. |