外源硝酸铵对厚皮甜瓜坐果节位叶片衰老及果实产量和品质的影响

Effects of Exogenous Ammonium Nitrate on Leaf Senescence in Fruiting Nodes and Yield and Qualities of Muskmelon Fruits

以厚皮甜瓜品种"迎春(F1)"为试材,研究了叶面喷施不同浓度硝酸铵(NH4NO3)对坐果节位叶片衰老及果实产量和品质的影响。结果表明:叶面喷施1.0、3.0、5.0 g·L-1的硝酸铵可不同程度地增加坐果节位叶片的叶绿素和可溶性蛋白质的含量,提高光合电子传递速率(ETR)、PSⅡ最大光化学效率(Fv/Fm)、PSⅡ实际光化学量子效率(Y(Ⅱ)),降低初始荧光参数(Fo),减缓MDA含量的增长,增加果实的可溶性固形物、可溶性糖和维生素C含量,但对单果质量影响不显著。表明叶面喷施3.0 g·L-1外源硝酸铵,对延缓厚皮甜瓜坐果节位叶片衰老,提高厚皮甜瓜果实品质的效果最佳。

Muskmelon cultivar ＇Yingchun（F1） ~ was used as test material, the study was conducted to investigate the effects of exogenous ammonium nitrate on the senescence of leaves in fruiting nodes and the yield and qualities of fruits of muskmelon. The results showed that by spraying different concentrations of exogenous ammonium nitrate solution （1.0,3.0,5.0 g ·L^-1） at the bearing-fruit flowering stage, the content of chlorophyll and soluble protein of the leaves in fruiting nodes increased at different degrees, besides, the apparent electron transport rate （ETR）, maximal photochemical efficiency（Fv/Fm）, quantum yield of PSII electron transport （Y Ⅱ ） were improved,Fo of the leaves of fruiting nodes was reduced. The increase of MDA content could be slowed down, the contents of soluble solids,soluble sugar and vitamin C in fruits increased, but there was no significant effect on single fruit weight. The best treatment with spraying 3.0 g · L-1 ammonium nitrate solution could be used to postpone the senescence of leaves in the fruiting nodes and improve the oualities of the fruits.