两种芽孢杆菌共用对感染柑桔黄龙病苗木的作用

以南丰蜜桔和沙糖桔黄龙病感病苗木为试材，利用贝莱斯芽孢杆菌TD2-1（Bacillus velezensisi TD2-1）和解淀粉芽孢杆菌TD2-2（Bacillus amyloliquefaciens TD2-2）对黄龙病感病苗木进行同步处理。采用qPCR和PCR方法对处理前和处理后的叶脉和枝皮进行了黄龙病病原的分子检测、生理指标分析和根部特征观察。结果表明：经两种菌剂15次的同步灌根处理，综合评价表明：南丰蜜桔苗木的黄龙病阳性率从100%降低至53.3%；与对照组相比，处理组的胼胝质含量降低了18.37%；超氧化物歧化酶、硫氧还蛋白氧化还原酶、过氧化氢酶和过氧化物酶均有所提高；褐变根系明显减少。感病的沙糖桔经过23次菌剂处理后,新根发达，褐变现象减轻。反相高效液相色谱分析表明：解淀粉芽孢杆菌TD2-2有表面活性素产生。

Effects of Two Bacillus strains treatment synchronously in Huanglongbing disease-infected nursery-grown plants

Huanglongbing disease-infected nursery growth plants, Citrus reticulita Blanco cv. Nanfeng tangerine and Citrus Reticulata Blanco cv. Shatangju were used as test materials, which were treated synchronously by Bacillus velezensisi TD2-1 and Bacillus amyloliquefaciens TD2-2 in this project. Huanglongbing disease molecular detection of midribs and barks were performed by both of Polymerase Chain Reaction (PCR) and quantitative PCR (qPCR) at before and after Bacillus strains treatment, and the physiological indexes and the characteristics of root structure were analyzed. The comprehensive evaluation of Huanglongbing disease of Nanfeng tangerine indicated that the positive rate of Huanglongbing disease were decreased from 100% to 53.3% in Citrus reticulita Blanco cv. Nanfeng tangerine for 15 times irrigation roots; In compared with the control, the callose content were decreased by 18.37%; The superoxide dismutase, thioredoxin oxidoreductase, catalase and peroxidase in the treatment group were increased; The browning roots were decreased obviously after treated with Bacillus strains treatment. After 23 times of Bacillus strains treatment, new roots were developed and browning was relieved obviously. Reversed-phase high performance liquid chromatography (RP-HPLC) analysis showed that Bacillus amyloliticum TD2-2 can produce surfactin.