大豆荚皮结构特征与点蜂缘蝽刺吸为害的相关性分析

Correlation analysis between structural characteristics of pod skin and stab-sucking damage of Riptortus pedestris

为探讨点蜂缘蝽(Riptortus pedestris Fabricius)对寄主大豆不同品种豆荚刺吸为害的选择性及其机制,本研究以40个大豆品种为寄主材料,采用罩网接虫随机选择法,观察不同大豆品种等密度豆荚被点蜂缘蝽刺吸危害情况,统计豆荚被刺点数、被刺率,籽粒被刺点数、被刺率等指标,同时系统观察测量各品种鼓粒期豆荚表面特征和荚皮解剖结构特征,分析点蜂缘蝽刺吸为害与豆荚表面(荚毛密度和长度)和荚皮解剖结构特征的相关性。结果表明:在40个供试品种中,表现出点蜂缘蝽刺吸频次较高和较低的品种均不超过5%;点蜂缘蝽对寄主豆荚选择性及刺吸为害程度在品种间存在差异;荚毛密度、长度和荚皮厚度及各解剖层厚度在品种间存在极显著差异。豆荚荚皮被刺点数、被刺率和籽粒被刺点数、被刺率之间呈显著正相关,被刺点数和被刺率与荚毛密度、长度和荚皮厚度均呈负相关,且与荚皮解剖结构内壁细胞组织层厚度呈显著负相关;豆荚被刺点数与内壁细胞组织层厚度之间分别符合线性函数方程y_(豆荚)=4.533-0.015x(F=6.271,P=0.013,r=-0.389),籽粒被刺点数与内壁细胞组织层厚度之间符合线性函数方程y_(籽粒)=1.579-0.005x(F=5.133,P=0.022,r=-0.362)。可见,大豆品种豆荚荚皮结构特征直接影响点蜂缘蝽对其刺吸为害程度,荚毛越密、越长和荚皮越厚其被害程度越轻,表现出的抗性越强,其中荚皮内壁细胞组织层厚度是影响品种抗性的最显著因子。该结果可为选育抗点蜂缘蝽大豆品种及其抗性评价提供科学依据。

This study aims to explore the piercing-sucking damage preference and mechanism of Riptortus pe-destris Fabricius to pods of different soybean varieties.Forty soybean varieties were planted at the same density in separate nets and inoculated with R.pedestris,and their piercing-sucking damage to pods of different soybean vari-eties was observed.The pierced points per pod,percentage of pierced pods,pierced points per seed,and percentage of pierced seeds were counted.The pod surface characteristics and the anatomical characteristics of pod skin were measured at the seed-filling stage.The correlations of R.pedestris damage with pod surface characteristics(pod hair density and length)and anatomical characteristics of pod skin were analyzed.The results showed that no more than 5%of the 40 test varieties were subjected to too high or too low piercing-sucking frequency of R.pedestris.The pref-erence and damage of R.pedestris varied among different varieties.The density and length of pod hairs and the thick-ness of pod skin and each anatomical layer also varied among different soybean varieties.The pierced points per pod and the percentage of pierced pods had significantly positive correlations with the pierced points per seed and the percentage of pierced seeds,respectively.The pierced points per pod and the percentage of pierced pods had negative correlations with pod hair density,pod hair length,and pod skin thickness and significantly negative corre-lations with the thickness of the inner cell tissue layer of the pod.The relationship between the pierced points per pod and the thickness of inner cell tissue layer was in accordance with the linear equation ypod=4.533-0.015x(F=6.271,P=0.013,r=-0.389)and that between the pierced points per seed and the thickness of inner cell tis-sue layer conformed to the linear equation yseed=1.579-0.005x(F=5.133,P=0.022,r=-0.362).The results indi-cated that the pod skin characteristics of soybean directly affected the piercing-sucking damage degree of R.pedes-tris.The soybean varieties with denser and longer pod hairs and thicker pod skin were generally subjected to milder damage,thus demonstrating stronger resistance.The thickness of the inner cell tissue layer of pod skin was the most significant factor affecting the resistance.The findings can provide a scientific basis for the selection and resistance evaluation of R.pedestris-resistant soybean varieties.