| Abstract: | Field trial, pot experiment with 45Ca tracer, plant analysis were used to investigate the characteristics of calcium uptake by young fruit of apple and its regulation by IAA, GA and NAA. The results indicated that calcium should be applied directly on the surface of young fruits because calcium applied on leaves could be hardly transfered to fruits. The proper Ca applying period was the first month of young fruits formation, and the proper concentration of CaCl2 applied was 0. 5%. Applying Ca directly on the surface of young fruits could increase the weight and quality of fruits. The process of transfering Ca2+ from fruit surface into pulp tissue could be accelerated by IAA, GA or NAA, which also led to an increment on 2% HOAc extractable Ca. Meanwhile, the Ca existed in the stalk and leaves could be strongly transported into fruits by applying IAA on the fruit surface, resulting in too much accumulation of Ca in fruit and bad quality of fruit, while no such sighs were observed with GA or NAA. |
