新疆野苹果枝条解剖结构与苹果小吉丁虫抗性的关系

【目的】 研究新疆野苹果枝条解剖结构与苹果小吉丁虫抗性的关系,为新疆野苹果抗虫育种、生物防治提供参考。【方法】 以新疆野苹果抗虫植株和敏感植株为材料,研究光学显微镜观察野苹果枝条内部解剖特征,分析抗虫表型形成原因。【结果】 新疆野苹果枝条木质部解剖,导管密度对抗虫性的影响较大,抗虫植株的导管密度低于敏感植株,分别为136.2 和163.1 n/μm²;木质部厚度、木化射线宽度对新疆野苹果植株的抗虫性影响不大。新疆野苹果抗、感植株的皮层厚度及韧皮部厚度都存在显著差异,其中抗虫植株韧皮部厚度低于敏感植株,分别为194.9和432.3 μm;抗虫植株皮层厚度高于敏感植株,分别为1 282.9和1 037.7 μm;周皮厚度差异不显著。【结论】 新疆野苹果枝条木质部导管密度越小,抗虫性越好,韧皮部厚度越低,皮层厚度高,抗虫表型越明显。

The Relationship between the Anatomical Structure of Malus sieversii Branches and the Resistance to Agrilusmali

【Objective】 To understand the relationship between the anatomical structure of Malus sieversii branches and the resistance to Agrilusmali and provide reference for the breeding and biological control of Malus sieversii.【Methods】 In this study, insect-resistant and sensitive plants of Malus sieversii were used as experimental materials.The internal anatomical characteristics of the Malus sieversii branches were observed with an optical microscope to explore the causes of the insect-resistant phenotype.【Result】 Under natural conditions, the anatomical structure of xylem of Malus sieversii branches was analyzed.The vessel density had a greater effect on insect resistance.The vessel density of insect-resistant plants was lower than that of sensitive plants, which were 136.2 and 163.1 n/μm², respectively; xylem thickness and xylem ray width had little effect on insect resistance of Malus sieversii plants.From the anatomical structure of the bark of Malus sieversii, the thickness of the cortex and phloem of resistant and susceptible Malus sieversiiplants were significantly different.The phloem thickness of insect-resistant plants was lower than that of sensitive plants, which were 194.9 and 432.3 μm, respectively; Cortex thickness of insect-resistant plants was higher than that of sensitive plants, which were 1,282.9 and 1,037.7 μm, respectively; there was no significant difference in the thickness of periderm.【Conclusion】 The anatomical structure of Malus sieversii branches has a great influence on the resistance to insects.The smaller the density of the xylem vessel of the branches, the better the insect resistance; the lower the thickness of the phloem, the higher the thickness of the cortex, and the more obvious the phenotype with insect resistance.