抗FOC4内生放线菌NJQG-3A1的定殖与防效研究

为明确生防菌NJQG-3A1菌株在香蕉植株根、球茎、假茎、叶和根际土壤中的定殖情况和对香蕉枯萎病的生防作用，为香蕉枯萎病的生防治理提供理论依据，采用抗生素标记法测定菌株NJQG-3A1的定殖能力，以盆栽试验测定其对香蕉枯萎病的防控效果。定殖测定结果表明：以重铬酸钾（100μg/mL）-氨苄青霉素（100μg/mL）标记的NJQG-3A1菌株，可在香蕉根际土壤和植株的根、球茎、假茎中定殖，定殖量表现为：根际土壤＞根＞球茎＞假茎＞叶；在土壤中的定殖量可达1×10⁵ cfu/g；在香蕉植株内定殖量为1×10²~1×10³ cfu/g。盆栽试验结果表明：经NJQG-3A1菌株的发酵液处理后，香蕉植株的株高、茎围、鲜重比对照（接种病原菌，只施用清水）分别提高了99.22%，44.60%，218.67%，与对照差异显著（P＞0.05）；同时，菌株NJQG-3A1对香蕉枯萎病的防控效果显著，叶部与根茎部的病情指数分别为15、10；病情防效为81.82%，88.98%。NJQG-3A1菌株可以在香蕉植株和根际土壤中定殖，且该菌株的发酵液对香蕉枯萎病具有良好的防控效果，对香蕉植株的生长具有促进作用。

Colonization of NJQG-3A1 Strain of Endophytic actinomycetes and Its Control Effect on Banana Fusarium Wilt

The colonization capacity of NJQG- 3A1 strain in banana plants and the rhizosphere was investigated, and the control efficacy of NJQG-3A1 against banana fusarium wilt was also studied, which will provide a theoretical basis for ecological control of the disease. The colonization trends of NJQG- 3A1 in banana plants and the rhizosphere was examined with the method of antibiotic-resistance. Furthermore, the effect of NJQG-3A1 against banana fusarium wilt was investigated by using pot experiment method. Results showed that NJQG- 3A1, tagged by the resistance of‘Ampicllin（100 μg/mL）- Potassium dichromate（100 μg/mL）＇, could colonized in roots, corms and pesudostems tissue of banana and rhizosphere soil stably.The population of NJQG-3A1 in different part was： rhizosphere soil〉roots〉corms〉pesudostems〉 leaves. It was also found that the population colonied in the rhizosphere and the banana plant was 1×10^5cfμ/g, 1×10^2to1×10^3cfμ/g respectively. In addition, the pot experiment result showed that the banana plant height, steam circumference, fresh weight were increased by 99.22%, 44.60%, 218.67% respectively, significantly different from the control（P〈0.05）, when treated with the strain NJQG-3A1 fermentation liquid strain NJQG-3A1 also showed obvious biocontrol effect on banana banana fusarium wilt, the disease indexes of leaves and root-steam were 15, 10 respectively, and the control efficacy were 81.82%, 88.98%, respectively. NJQG- 3A1 could colonize in the banana plant and the rhizosphere. The strain NJQG-3A1 fermentation liquid showed strong disease biocontrol effect on banana fusarium wilt, as well as promotion effect on banana plant growth.