采前喷钙对葡萄耐藏力的影响

EFFECTS OF PREHARVEST CALCIUM SPRAY ON THE STORAGE OF TABLE GRAPES

用0.5％、1.0％、1.5％Ca(NO_3)_2溶液采前喷布‘粉红太妃’和‘龙眼’葡萄果穗。果实采收后在 3-5℃下、用聚乙烯薄膜包装贮藏122-133天,所有钙处理都提高了果实耐藏力,以晚期1.5％浓度综合效果较好,‘粉红太妃’和‘龙眼’葡萄损耗率分别减少76.2％和64.3％,果实耐压力分别提高406g和367g,果柄耐拉力分别提高130g和79g。钙处理推迟了贮期内果糖/总酸比值高峰期,延长了风味佳期;抑制了多酚氧化酶的活性,减少了单宁、 VC等物质的氧化损失和浆果内部褐变;减小了果实膜透性变化;减缓了可溶性果胶的损失,其含量在贮藏末期最多比对照高104.2％。采前喷钙提高了果实各部位的钙素水平,全果总钙含量最多提高了39.3％。采前30-40天处理,1.0％浓度吸收率最高;采前10天处理,1.5％浓度吸收率最高,并预测可随钙浓度加大进一步提高。

The grapc-clustcrs(cv. 'Taifi rose' and 'Long yan' ) were sprayed with Ca ( NO_3 )_2 solution of 0.5, 1.0 and 1.5% before harvest, and were stored for 123 or 133 days at 3-5℃ in polythene bags. It was found that calcium treatment increased the storage life of the berries. The results of 1.5% Ca ( N0_3 )_2 solution sprayed in the later period are better. Both 'Taifi rose' and'Long yan'rcduced losses by 76.2% and 64.3%, enhanced turgor pressure of berries by 406 and 367 ( g ) , and enhanced attachment of stems to the fruit by 130 and 79 ( g ) , respectively. The main physiological and biochemical changes due to calcium treatments are as follows; Losses of soluble pectin were retarded and its content was higher by 104.2% in the end of storage. The ratio of fructose to total acidity changed as the model of 'parabola' with the storage time prolonged, and the peak value of the curve was putted off. Calcium inhibited the activity of polyphendoxidase and decreased the loss of both tannin and ascorbic acid, so the internal browning in berry was far less. Solute leakage was reduced. Total calcium content of whole berry raised 39.3% maximally. When 1.0% Ca was sprayed 30-40 days before harvest, the calcium uptake is most, and so does the 1.5% Ca used 10 days before harvest. It can be predicted that when Ca treatment was made later, the uptake rate would be further increased as solution concentration raised.