溶磷真菌的分离鉴定及其对新疆加工番茄种子萌发的影响

Isolation and Identification of Phosphate- Solubilizing Microorganisms and Its Effects on Germination of Xingjiang Processing Tomato Seed

溶磷真菌是能够将难溶磷转变为可溶性磷的一类微生物。为了提高磷素利用率,本研究采用平板培养法从加工番茄根际土壤中分离筛选到2株溶磷能力较强的菌株,分别命名为3-1和3-2,结合菌落形态特征和ITS r DNA序列分析,将菌株分别鉴定为黑曲霉(Aspergillus niger)和黄曲霉(Aspergillus flavus)。用以Ca3(PO4)2为唯一磷源的培养基对其溶磷能力进行测定,发现菌株3-1和3-2对Ca3(PO4)2的溶磷量分别是368.7 mg/L、142.2 mg/L。通过不同浓度的单菌菌液和混和菌液处理新疆加工番茄里格尔(87-5)种子,发现不同菌株、不同的菌液浓度对加工番茄种子萌发影响显著,发芽指数随菌液浓度的降低而增加;菌株3-2菌液OD600光密度值为0.1时,发芽率最高,达(94.5±1.0)%;单菌株处理组的发芽势随着菌液浓度的降低而增加。本研究结果为获得有益于新疆加工番茄生产应用的溶磷菌株提供了重要参考。

Phosphate- solubilizing fungi is a kind of microorganism which can transform insoluble phosphorus into soluble phosphorus.To improve utilization efficiency of phosphorus in agriculture,here we isolated two phosphate- solubilizing fungi that show high phosphate- solubilizing ability labeled as 3- 1 and 3- 2 from processing tomato rhizosphere soil.According to theircolonial morphological characteristics and ITS rDNA sequence analysis,strain 3- 1 and 3- 2 were identified as Aspergillus nigerand Aspergillus flavus,respectively.We found that the phosphate- solubilizing ability of strain 3- 1 and 3- 2 were 368.7 mg and142.2 mg soluble phosphorus perlitermedium,by using Ca3(PO4)2phosphorus source medium.Meanwhile,theireffects on seed germination were researched by soaking Xingjiang Processing Tomato seed with different fermentation broth of strains and concentrations.The results showed that different strain and fermentation broth concentration influence significantly tomato seed germination.The gemination index of tomato seeds increased with lowerconcentration of the fermentation broth of fungi.When the OD600 optical density value of fermentation liquid was 0.1,the highest germination rate of strain 3- 2 appeared,which reached as(94.5±1.0)%.Furthermore,with increasing concentration of fermentation broth,the germination potential of single strain treatments were reduced.Ourresearch results provided an important reference forobtaining phosphate- solubilizing microorganisms,which may be beneficial to the application of Xinjiang processing tomato production.