壳寡糖对黄瓜种子萌发和幼苗生长及光合特性的影响

摘 要: 应用不同浓度的壳寡糖处理黄瓜种子和幼苗，得出壳寡糖在低浓度时能够促进黄瓜种子发芽，最适浓度为0.1 mgL-1。试验结果同时表明低浓度壳寡糖对黄瓜幼苗生长有促进作用，使得幼苗株高、叶面积等生长指标，与对照相比均显著增加；功能叶片的叶绿素含量、净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、胞间CO2浓度（Ci）显著升高; 气孔限制值(Ls)显著降低。而高浓度（100 mgL-1）壳寡糖则抑制生长。促进黄瓜幼苗生长最适的壳寡糖浓度为0.1 mgL-1，施用两次的效果优于一次。

Effects of Oligochitosan on the Seed Germination Seedling Growth and Photosynthetic Characters of Cucumber

Abstract: Different concentrations of oligochitosan were used on cucumber seeds and seedlings,the results indi-cated: low conc.of oligochitosan promoted the germination of cucumber, the most optimum concentration of oli-gochitosan was 0.1 mgL-1.low conc.of oligochitosan promoted the growth of cucumber seedlings,the heights of seedlings and the areas of functional leaves were increased significantly(P < 0.05) which compared with ck, the contents of chlorophyll , the net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr)of tobacco seedlings were increased significantly (P < 0.05), while stomatal limita-tion (Ls) was reduced significantly (P<0.05) on cucumber seedlings.High conc.of oligochitosan (100 mgL-1)restrained the growth of cucumber seedlings. the most optimum concentration of oligochitosan for cucumber seedlings was 0.1mgL-1. The effect of using twice oligochitosan was better than using once.