Exploration of novel genetic resources against root-knot nematode (RKN) is necessary to strengthen the resistance breeding program in cultivated rice, and investigations on the role of genotype-specific root anatomy in conferring a structural barrier against nematode invasion are largely underexplored. Here, we reported a highly-resistant rice germplasm Phule Radha that conferred remarkably lower RKN parasitic fitness in terms of reduced penetration and delayed development and reproduction when compared with susceptible cultivar PB1121. Using histological and biochemical analyses, we demonstrated that an enhanced suberin deposition in the exodermal root tip tissue of Phule Radha compared to PB1121 can effectively form a penetrative barrier against RKN infection, and this preformed barrier in the control tissue did not necessarily alter to a greater extent when challenged with RKN stress. Using qRT-PCR analysis, we showed that a number of suberin biosynthesis genes were greatly expressed in the exodermis of Phule Radha compared to PB1121. In sum, the present study established the role of rice exodermal barrier system in defense against an important soil-borne pathogen.

为了增强栽培稻的抗性育种计划，必须探索针对根结线虫的新型遗传资源，而关于基因型特异性根解剖在赋予线虫入侵结构性屏障方面的作用的研究还很不足。在这里，我们报道了一种高抗性水稻种质Phule Radha，与易感品种PB1121相比，在降低穿透力和延迟发育与繁殖方面，它们显着降低了RKN寄生虫的适应性。使用组织学和生化分析，我们证明，与PB1121相比，在Phule Radha的表皮根尖组织中增强的Suberin沉积可以有效地形成针对RKN感染的渗透屏障，当受到RKN压力攻击时，对照组织中预先形成的障碍并不一定会在更大程度上改变。使用qRT-PCR分析，我们发现，与PB1121相比，在Phule Radha的外皮中大量表达了suberin生物合成基因。总而言之，本研究建立了水稻表皮屏障系统在防御重要的土壤传播病原体中的作用。