钙对香蕉采后乙烯释放的抑制

本实验用CaCl_2溶液对香蕉(Musa acuminata cf. 'Dwarf Davendish')组织进行真空浸透处理,研究Ca~(2 )对香蕉采后乙烯释放、EFE活性、ACC水平以及ACC/MACC比值的影响。结果表明,Ca~(2 )处理可抑制香蕉果皮和果肉组织乙烯生成,对抑制果皮的乙烯生成尤为明显。Ca~(2 )处理还可降低内源ACC水平,抑制EFE活性。结果还显示,Ca~(2 )处理对组织中ACC/MACC比值有一定影响。

INHIBITION OF CALCIUM ON ETHYLENE PRODUCTION IN POSTHARVEST BANANA FRUITS

Banana, ( Musa acuminata cv. 'Dwarf Davendish' ) fruit tissues were vacuum infiltrated with CaCl2 solutions in order to determine the influence of calcium upon ethylene production, EFE activity, ACC content and ACC/MACC ratio. The results showed that calcium treatment inhibited ethylene production in both peel and pulp, particularly in peel. Ethylene production in peel treated with 3 concentrations of CaCl2 solutions (0.2, 0.6 and 0.8 mol/L) remained lower than that in the control throughout the period of 2-6 hours after treatment.Ethylene production in pulp infiltrated with 0.2 and 0.6 mol/L CaCl2 were inhibited during 2-3 hours after treatment,and ethylene production was reduced by 0.8mol/L CaCl2 treatment throughout 2-6 hours (Fig. 1 ) . Calcium infiltration (with 0,2, 0.4 and 1.0 mol/L CaCl2 ) lowered the internal ACC level in both peel and pulp (Tab. 1).EFE activity in peel and pulp treated with 0.05, 0.1, 0.2 and 0.5 mol/L CaCl2 were reduced (Tab. 2 ) . The result also showed that calcium treatment contributed to the change of ACC/MACC ratio (Fig. 2) . The results suggest that the inhibition of Ca2 on ethylene production in banana tissues, does not merely act on the step of ACC to ethylene, Ca2 may also regulate both ACC biosyn thesis and the bioconversion of ACC to MACC.