Variation in susceptibility of 28 Prunus rootstock genotypes to the causal agents of Armillaria root rot, Armillaria mellea, A. solidipes, and Desarmillaria tabescens, were studied by conducting in vitro root screening assays. Root segments with wounded and intact periderm were placed next to and on the top of the fungal cultures. At day 21, the percent success of fungal penetration and the circumferential and longitudinal lengths of fungal growth were measured. A parallel investigation using the inoculated root segments was carried out to characterize the active host defense mechanisms involved, including anatomical responses in bark and wood. Overall, the success of penetration and the longitudinal and circumferential spread of Armillaria spp. and D. tabescens were significantly different among various Prunus rootstock genotypes. None of the tested rootstock genotypes were completely resistant to infection. However, plum and plum derived rootstocks, and some of the cherry genotypes were less susceptible to infection compared to the peach genotypes. The host’s ability to limit infection by Armillaria spp. and D. tabescens was not limited to a single mechanism but appeared to be regulated by several collective nonspecific host responses acting together. Differential levels of a series of non-specific coordinated events were triggered in Prunus genotypes such as the formation of new callus tissue on the root surface, a colored reaction zone, necrophylactic periderm, new cells, and new vascular cambium to compartmentalize the pathogen. The host responses were elevated in the genotypes with low level of infection as compared to highly infected genotypes.

通过进行体外根筛选试验，研究了28种李子砧木基因型对蜜环菌根腐病，蜜环菌，固结线虫和德氏Desarmillaria tabescens病因的敏感性变化。带有受伤和完整皮层的根段放置在真菌培养物的旁边和顶部。在第21天，测量真菌渗透的成功百分比以及真菌生长的周向和纵向长度。使用接种的根段进行了平行研究，以鉴定涉及的主动宿主防御机制，包括树皮和木材的解剖反应。总体而言，蜜环菌的渗透和纵向和圆周扩散的成功spp。和D. tabescens在各种李属砧木基因型之间显着不同。测试的砧木基因型均不能完全抵抗感染。但是，与桃子基因型相比，李子和李子衍生的砧木以及某些樱桃基因型不易感染。宿主限制蜜环菌属菌感染的能力。和D. tabescens不仅限于单一机制，而且似乎受到共同作用的几个集体非特异性宿主反应的调节。在李属中触发了一系列非特异性协调事件的差异水平基因型，例如在根表面形成新的愈伤组织，有色的反应区，坏死性皮层，新细胞和新的血管形成层，以分隔病原体。与高度感染的基因型相比，感染水平低的基因型中的宿主反应升高。