The results of inoculation of F2 population verified the resistance to Xoo results from the expressing of Ird40. After dye with Trypan blue and DAB in leaf of Ird40, programmed cell death and deposition of H2O2 was observed during lesion development.

• lrd40与野生型杂交F_2代接种结果证实，lrd40的抗白叶枯与类病变的表现是一致的。 锥虫蓝(trypan blue)染色观察到lrd40的类病变发生是一个程序性细胞死亡过程，经二氨基联苯胺(diamino benzidine，DAB)染色检测到lrd40的类病变表达时，叶片上产生H_2O_2沉淀。