褪黑素对设施延后栽培‘红地球’葡萄果实品质的影响

为探明褪黑素对鲜食葡萄果实品质的影响,并为褪黑素改善果实品质及其在生产中的应用提供理论依据。以‘红地球’葡萄品种为试验材料,采用设施延后栽培模式,在葡萄转色前,采用50、100、200、500μmol/L褪黑素水溶液进行全树喷施2次,以喷清水作为对照,研究不同浓度褪黑素处理对葡萄果实形态指标(单粒重、纵横径和果形指数)、果皮色泽(L*、a*、b*)、可溶性固形物含量、可滴定酸含量、可溶性糖含量、糖酸比、维生素C含量以及酚类物质(总酚、黄酮和花色苷)含量的影响。结果表明:不同浓度褪黑素处理间的果实品质各指标(果形指数、果皮色泽除外)与对照间存在显著性差异,褪黑素处理可以显著提高果实单粒重、纵径,增加果实中可溶性固形物含量、可溶性糖含量和糖酸比,并且有利于果实中酚类物质(总酚、黄酮和花色苷)积累,降低果实横径和可滴定酸含量;尤以100μmol/L褪黑素处理与对照间差异最大、效果最明显。综合分析认为,在葡萄转色前喷施褪黑素,可以改善设施延后栽培‘红地球’果实品质,其中以100μmol/L褪黑素处理对改善‘红地球’葡萄果实品质效果最好。

Effects of melatonin on quality of'Red Globe'grape under delayed cultivation in greenhouse

In order to understand the effects of melatonin on quality of table grape and provide the theoretical foundations for melatonin of improving the fruit quality and applying in cultivation, we took the renowned table grape ‘Red Globe’ as the material to do the field experiment that includes the four different concentrations of melatonin(50, 100, 200 and 500 μmol/L) which were applied to spray the vines respectively before color-changing period for two times. We carried out to study the fruit morphological indexes(single fruit weight, vertical diameter, transverse diameter and fruit shape), color indexes(L*, a* and b*), soluble sugar content, soluble solids content, titratable acidity content and sugar-acid ratio and phenol compounds(total phenol, flavonoid and anthocyanin content). The results showed that there was a significant difference on quality indices except the color indexes and fruit shape between the melatonin treatments and control. Melatonin treatments could enhance the single fruit weight and vertical diameter, and increase the soluble sugar content, soluble solids content and sugar-acid ratio, and be advantageous to the accumulation of phenol compounds, but reduce the transverse diameter and titratable acidity content at the same time. It is considered that the spraying of melatonin can improve the quality of ‘Red Globe’ grape under delayed cultivation in greenhouse. Among the treatments, the 100 μmol/L melatonin treatment was the most effective one.