Amaranthus (Amaranthus tricolor L.) is a popular vegetable crop grown in South India. Leaves being the main economic part, foliar blight disease caused by Rhizoctonia solani Kühn greatly reduces marketability of the produce. Isolation and characterization of endospore-forming endophytic bacteria (EEB) from endorhizosphere of Amaranthus spp., and their effects on plant growth promotion and suppression of leaf blight disease in a susceptible amaranthus variety are reported here. Eight EEB strains were isolated from roots of healthy Amaranthus spp. through a novel “two-step” enrichment process. They were identified as Bacillus spp. by morphological, biochemical and molecular characterization. In vitro screening tests were performed for plant growth promotion and antagonism against R. solani, and greenhouse experiments were conducted with selected superior isolates. Inoculation with EEB isolate Bacillus amyloliquefaciens GR1, obtained from the leaf blight resistant green amaranthus variety CO-1, significantly improved growth of red amaranthus variety Arun. Fresh weight of shoot portions, the economical part of the crop, recorded 35% increment over that in the uninoculated control. Bacillus sp. WR1, isolated from the leaf blight resistant wild species Amaranthus viridis, suppressed the blight disease in the susceptible red variety Arun to a tune of 41% compared to the pathogen inoculated control. Spray application of the recommended contact fungicide, mancozeb (0.2%), was less efficient in suppressing the disease compared to bacterization of plants with three of the EEB from amaranthus.

苋菜（Amaranthus tricolor L.）是印度南部种植的一种受欢迎的蔬菜作物。叶子是主要的经济部分，由Rhizoctonia solani Kühn引起的叶枯病大大降低了产品的适销性。本文报道了苋属植物根际内形成内生孢子的内生细菌 (EEB) 的分离和表征，以及它们对促进植物生长和抑制易感苋属植物叶枯病的影响。从健康苋属植物的根中分离出八种 EEB 菌株。通过新颖的“两步”浓缩过程。它们被鉴定为芽孢杆菌属。通过形态学、生化和分子表征。进行了植物生长促进和对抗茄病菌的体外筛选试验，并用选定的优良分离株进行了温室试验。接种 EEB 分离株解淀粉芽孢杆菌GR1，从抗叶枯病的绿色苋菜品种 CO-1 中获得，显着改善了红色苋菜品种 Arun 的生长。芽部分的鲜重（作物的经济部分）比未接种的对照增加了 35%。芽孢杆菌属。WR1，从抗叶枯病的野生种Amaranthus viridis 中分离，与病原体接种的对照相比，将易感红色品种 Arun 的枯萎病抑制了 41%。与使用来自苋菜的三种 EEB 对植物进行杀菌相比，喷洒推荐的接触杀真菌剂代森锰锌 (0.2%) 在抑制疾病方面的效率较低。