叶面喷施寡糖对生菜生长和品质的调节作用

Effect of Different Oligosaccharides by Spraying on Plant Growth and Quality in Lettuce

为探究不同单一寡糖和复配寡糖对作物生长发育、产量及品质的影响,选择生长周期较短的生菜品种“意大利耐抽薹”作为研究对象,以80mg·L^?1的纤维寡糖(ZH-A)、低聚木糖(ZH-B)、甲壳低聚糖(ZH-C)和以上3种寡糖等质量比的复配寡糖(ZH-M)以及多糖海藻酸钠(GY-D)对定植后的生菜进行4次叶面喷施处理,以喷清水为对照(CK)。从定植后的第3天(三叶一心)开始,每隔2d连续喷施4次,至采收期(定植23d)测定生菜的生长特征(生物量、叶面积、荧光光合)、根系表型特征(根长、根表面积、根体积)以及品质特征(可溶性糖、叶绿素、Vc、硝酸盐)。结果表明:单一寡糖、复配寡糖及海藻酸钠多糖处理均能显著增加生菜生物量;纤维寡糖(ZH-A)对促进根系生长及降低硝酸盐含量具有显著效果;甲壳低聚糖(ZH-C)对叶绿素含量、最大光化学效率Fv/Fm及可溶性糖含量有显著的提高作用;复配寡糖对生菜地上部、地下部及品质的增长和提升效果明显优于单一寡糖和多糖,采收期地上部鲜重及叶面积分别增加52.58%和57.60%,根干重、总根长、总体积及总表面积分别增加35.07%、89.10%、49.23%和40.68%,可溶性糖增加25.20%,叶绿素含量增加21.50%,Vc含量提高12.08%,硝酸盐含量降低27.65%。综上可知,不同寡糖对生菜生长特征和生理性状的作用效果和调控机制具有明显差异;复配寡糖对生菜促生长和提品质的调节效果显著优于单一寡糖。

Experiments in climate chamber were performed to explore the levels of various components of single and mixed oligosaccharides on growth,yield and performance of lettuce.A short-growing type of lettuce(var.ramosa Hort)and three oligosaccharides,such as cello-oligosaccharides(ZH-A),xylo-oligosaccharides(ZH-B),and chitosan oligosaccharides(ZH-C)were selected.The mixed oligosaccharides(ZH-M)(Mass Ratio,ZH-A:ZH-B:ZH-C=1:1:1)and the conventional polysaccharide sodium alginates(GY-D)were prepared for the experiment.80mg·L^?1 of each was applied 4 times(every 3 days)to lettuce by foliar spraying after three days of planting and the water(CK)was used as a control.Growth characteristics(biomass,leaf area and fluorescence photosynthetic),root phenotypic characteristics(root length,root surface area and root volume)and the quality characteristics(soluble sugar,chlorophyll,Vc,and nitrate contents)of lettuce were measured at the harvest stage(23 days after planting).The results showed that foliage spraying can significantly increase the biomass of lettuce in all single oligosaccharide treatments and the(GY-D)treatment.The cello-oligosaccharide showed the significant increase in root growth and decrease in nitrate content.The chitosan oligosaccharide showed the substantial increase in chlorophyll content,the maximum photosynthetic efficiency(Fv/Fm)and the soluble sugar content.The mixed oligosaccharides(ZH-M)showed the best effects on lettuce growth,such as the above and underground biomass and the quality characters.In the ZH-M treatment,the fresh weight and leaf area index increased by 52.58%and 57.60%at the harvest stage.And,root dry weight,total root lengths,root total volume and root surface area increased by 35.07%,89.10%,49.23%and 40.68%,respectively.The content of soluble sugar,chlorophyll,and Vc rose by 25.20%,21.50%and 12.08%respectively,while the nitrate content dropped by 27.65%.In conclusion,significant differences in interaction and regulation regime were found among the different oligosaccharides on plant physiology and growth.Compared with the single oligosaccharide,the mixed oligosaccharides showed the multiplying influences on plant growth and quality improving.