壳聚糖对桃果实品质的影响

Effect of Chitosan on Peach Fruit Quality

为了筛选出能提高桃果实品质的最佳壳聚糖浓度,以早熟桃品种早蜜为试材,在桃果实进入第二次快速膨大期时分别用浓度为0(CK)、1、2、4和6 g/L的壳聚糖进行叶面喷施处理,考察了不同浓度壳聚糖对桃果实品质的影响。结果表明:喷施壳聚糖处理有降低桃果实单果重、纵横径,增加果实硬度的趋势;虽然不同浓度壳聚糖处理均降低了桃果实中葡萄糖含量,但壳聚糖浓度1和2 g/L处理的可溶性固形物含量显著高于CK,壳聚糖浓度1 g/L处理的维生素C含量较CK显著提高9.56%,壳聚糖浓度1和2 g/L处理的可溶性糖含量分别较CK显著增加9.40%和10.11%,壳聚糖浓度2 g/L处理的蔗糖含量较CK显著提高52.52%,果糖和山梨醇含量以壳聚糖浓度1 g/L处理最高,分别较CK显著提高19.96%和16.67%,其次是壳聚糖浓度2 g/L处理,也显著高于CK;不同浓度壳聚糖处理均降低了桃果实氮、磷、铁和镁的含量,但增加了钾、硼和钙的含量;桃果实中PAL、APX和POD活性均是壳聚糖浓度1和2 g/L处理显著高于CK。综合考虑各项指标,改善桃果实品质的最佳壳聚糖浓度为1和2 g/L。

The optimal concentration of chitosan for improving peach fruit quality was determined.Chitosan[0(CK),1,2,4,and 6 g/L]was sprayed on the leaves of the early maturing peach variety'Zaomi'at the second stage of fruit expansion.The effect of chitosan on peach fruit quality was studied.The results showed that chitosan decreased the single fruit mass and longitudinal and transverse diameters and increased the fruit hardness.Different concentrations of chitosan reduced the glucose content in peach fruits.Compared with CK,chitosan applied at 1 and 2 g/L significantly increased the content of soluble solids;chitosan applied at 1 g/L increased the vitamin C content by 9.56%;chitosan applied at 1 and 2 g/L increased the soluble sugar content by 9.40%and 10.11%,respectively;chitosan applied at 2 g/L increased the sucrose content by 52.52%;chitosan applied at 1 g/L increased the fructose and sorbitol content by 19.96%and 16.67%,respectively.Different concentrations of chitosan reduced the content of nitrogen,phosphorus,iron,and magnesium and increased the content of potassium,boron,and calcium in peach fruits.The activities of phenylalanine aminolyase(PAL),ascorbate peroxidase(APX),and peroxidase(POD)in peach fruits were significantly increased after the application of 1 and 2 g/L chitosan.Considering all the indicators above,we suggest that chitosan can be applied at 1 and 2 g/L to improve peach fruit quality.