Q型烟粉虱为害对不同辣椒品种叶绿素及营养物质的影响

Contents of chlorophyll and nutrients in pepper varieties exposed to Bemisia tabaci

为明确辣椒品种对烟粉虱的抗性机制,以不同抗性程度的辣椒为试验材料,研究了其受Q型烟粉虱危害后体内生理指标的变化。结果显示,Q型烟粉虱危害后,辣椒叶绿素和可溶性糖含量均较对照(未接虫)增加,其中抗性品种(苏椒5号、新研988椒王)叶绿素含量增加显著(P<0.05);可溶性糖含量以抗性品种增幅最大(P<0.05),中抗品种(萧新九号、湘辛三号)次之(P<0.05),感虫品种(港上红尖椒、大禹牛角王)的增幅最小。烟粉虱危害后所有参试品种除中抗品种湘辛三号外,其余品种的可溶性蛋白含量均较对照降低;所有参试品种的游离脯氨酸含量均显著降低(P<0.05),感虫品种港上红尖椒、大禹牛角王的游离脯氨酸含量均显著高于高抗及中抗品种(P<0.05)。因此,辣椒品种对Q型烟粉虱的抗性强弱与叶片叶绿素含量、可溶性糖含量、游离脯氨酸含量有关,而与可溶性蛋白含量无明显相关。

To define the resistance mechanism of pepper against whitefly（Bemisia tabaci）,the pepper varieties with different resistant levels were detected for the changes of physiological indexes after infestation of B.tabaci.The chlorophyll and soluble sugar contents in pepper leaves eaten by Q biotype whitefly were increased compared to control（not exposed to whitefly）,and resistant varieties,Sujiao 5 and Xinyan 988 pepper king,exhibited the highest increment（P〈0.05）.The contents of soluble sugar showed the largest increase in resistant varieties,followed by moderately-resistant varieties,Xiaoxin 9 and Xiangxin 3,and the smallest was seen in susceptible varieties,Gangshanghongjianjiao and Dayuniujiaowang.All the pepper varieties exposed to whitefly except for Xiangjin 3 were lower in the soluble protein contents than control.The free proline contents were reduced（P〈0.05） in all six pepper varieties by whitefly infestation,however,they were higher in susceptible varieties（Gangshanghong pepper and Dayuniujiaowang） than in resistant and moderatelyresistant varieties（P〈0.05）.These results suggested that resistant level of the tested six different varieties against the Q biotype whitefly was related to the content of chlorophyll,soluble sugar and free proline,but not to the soluble protein content in pepper leaves.