外源6-BA和GA-_3对甜瓜叶片衰老过程中生理特性及产量影响

Effects of Exogenous 6-BA and GA-_3 on Physiological Characteristics During Leaf Senescence and Yield of Melon

为探明植物激素在调控甜瓜衰老中的作用机制和防止甜瓜早衰中应用提供理论基础,以早熟品种‘F35’和中晚熟品种‘F28’为试材,分别在苗期、伸蔓期喷施6-BA和GA-_3,研究不同浓度植物激素对叶片叶绿素、可溶性蛋白和MDA含量、相关抗氧化酶活性等生理生化指标及产量的影响。结果表明,适宜浓度的6-BA和GA-_3均可提高甜瓜叶片叶绿素和SOD酶活性,降低MDA含量,有效地延缓叶片衰老,提高产量。其中,以6-BA 60 mg/L和GA-_3 80 mg/L处理效果明显优于其他处理。不同甜瓜品种对外源激素的敏感程度不同,总体来讲,早熟品种的敏感程度要高于中晚熟品种。

The study aims to investigate action mechanism of plant hormone regulating melon senescence, andprovide a theoretical basis for preventing premature senescence of melon. Early-maturing variety ‘F35＇ andmiddle- late season variety ‘F28＇ were used as the test materials, the effects of different concentrations of 6- BA and GA-_3 on physiological characteristics including chlorophyll, soluble protein and malondialdehyde（MDA） content, relative antioxidant enzyme activity during leaf senescence and yield were determined. Theresults showed that suitable concentrations of both 6-BA and GA-_3 could improve the chlorophyll content andSOD activity, and decrease MDA content, delay leaf aging and increase the yield of melon, and the effect of 6- BA 60 mg/L and GA-_380 mg/L were significantly better than that of the other treatments. The sensitivedegrees of different cultivars to exogenous hormones were different, in general, the degrees of early-maturingcultivars were higher than those of middle-late season cultivars.