论文部分内容阅读
为进一步研究苹果枝干对轮纹病的抗病机理,以红玉×金冠杂种后代中表现不同抗病性的杂种实生树为试材,分析了不同抗病性的实生树枝条皮孔密度差异,接种轮纹病菌丝后枝条皮层木质素含量的变化,并采用扫描电镜技术,观察了接种点表面超微结构的变化。对20份不同抗性实生树1年生枝条皮孔密度的调查表明,在本分离群体内,皮孔密度与抗病性未见显著相关性。对苹果枝干轮纹病抗病、感病的杂种实生树进行接种,菌丝均可从皮孔侵入,但抗病的杂种实生树表现为致瘤性弱。接种病原后抗病和感病材料均会导致木质素含量的增加,但抗病材料木质素的增加量显著高于感病材料,表明木质素含量的激增与抗病性相关。金冠×红玉杂种后代中抗病单株的抗病性并非表现为抑制病原菌丝侵入,而表现为侵染后,通过诱导皮层木质素积累,抑制病原菌丝在寄主体内的扩展。
In order to further study the mechanism of apple tree stem rot disease resistance, taking the hybrid seedlings of hybrids with different disease resistances in the hybrids of Hongyu × Golden Crown hybrids as test materials, the density differences of the seedling branches of different branches were analyzed , The changes of lignin content in the branch cortex after inoculation of S. melastris were observed. The changes of the ultrastructure on the surface of the inoculation point were observed by scanning electron microscopy. A survey of the density of 1-year-old branches of 20 different resistant seedlings showed that there was no significant correlation between the density of the skins and the disease resistance in this segregation population. Inoculation of the hybrid tree of resistance to disease and susceptible apple blight, the mycelium could invade from the lenticel, but the disease-resistant hybrid tree was tumorigenic. Disease resistance and susceptible materials inoculated with pathogen resulted in an increase of lignin content, but the increase of lignin in disease-resistant material was significantly higher than that in susceptible materials, indicating that the increase of lignin content is related to disease resistance. The disease resistance of resistant individuals in the hybrids of Golden Delicious × Red Hybrid did not show the inhibition of pathogenic mycelium invasion, but showed the expansion of the pathogenic mycelium in the host by inducing cortical lignin accumulation after infection.