蔗叶堆肥中一株泡盛曲霉溶磷能力的鉴定及其对辣椒的促生效果

A phosphorus-dissolving Aspergillus awamori strain from sugarcane leaf compost for growth promotion of pepper

摘要:

[目的] 从甘蔗叶堆肥中分离筛选具有高效溶磷及促生功能的菌株，为微生物肥料制备提供一种可利用的菌种资源。[方法] 以Ca₃（PO₄）₂和Zn₃（PO₄）₂为磷源，进行平板溶磷筛选实验；采用形态学特征和ITS rDNA序列分析法进行菌种鉴定；采用液体摇瓶培养测定菌株的溶磷能力；将溶磷菌接种至辣椒幼苗根部分析其促生效应。[结果] 从堆肥中筛选得到1株高效溶磷真菌DC30-2-P1，经鉴定为泡盛曲霉（Aspergillus awamori），菌株在Ca₃（PO₄）₂和Zn₃（PO₄）₂培养基的菌落直径（d）分别为55.33 mm和45.00 mm，透明圈直径（D）分别为65.33 mm和67.67 mm，（D/d）分别为1.16和1.50，菌株溶磷效果明显；在以Ca₃（PO₄）₂（5 g/L）为磷源的液体培养基培养至96 h，有效磷含量达到2973.85 mg/L。盆栽试验结果表明接种DC30-2-P1对辣椒生长具有明显促进作用，与无添加溶磷菌处理组比较，其地上部鲜重和干重分别增加了18.6%和43.5%，地下部鲜重和干重分别增加了30.2%和25%，株高增加了13.6%，叶绿素含量增加了44.9%，植物全磷含量和土壤有效磷含量均提高了80%以上。[结论] 筛选到的菌株DC30-2-P1在溶解难溶性磷化合物、促进作物对磷的吸收和生长有良好效应，为微生物制剂的开发提供菌株资源。

关键词:溶磷真菌;泡盛曲霉;溶磷作用;促生作用

Abstract:

[Objective] Isolation of strains with high-efficiency of phosphorus-dissolving and growth-promoting functions from sugarcane leaf compost has provided available microbial resources for bio-fertilizers production. [Methods] Phosphorus-dissolving strains were screened from insoluble inorganic phosphorus media containing Ca₃(PO₄)₂ or Zn₃(PO₄)₂, and identified by morphological characteristics and ITS rDNA sequence analysis. The phosphorus-dissolving ability of the strains was determined by the halo zone and molybdenum antimony colorimetric methods, and the growth-promoting ability of the strain was analyzed by pot experiment of pepper. [Results] Strain DC30-2-P1 was screened from the compost and identified as Aspergillus awamori. The diameter of the colony of the strains (d) was 55.33 mm and 45.00 mm, the halo zone (D) was 65.33 mm and 67.67 mm, and the D/d value was 1.16 and 1.50 on the medium with Ca₃(PO₄)₂ and Zn₃(PO₄)₂, respectively. After 96 hours of cultivation in a liquid medium with Ca₃(PO₄)₂ as the phosphorus source, the available phosphorus content reached 2974 mg/L. The results indicated that strain DC30-2-P1 had a significant effect on dissolving phosphorus. The results of the pot experiment show that the inoculation of DC30-2-P1 promoted the growth of pepper. Compared with the treatment group without phosphate solubilizing fungi, the above-ground fresh and dry weight increased by 18.6% and 43.5%, the under-ground fresh and dry weight increased by 30.2% and 25%, plant height increased by 13.6%, and chlorophyll content increased by 44.9%, both plant total phosphorus content and soil available phosphorus content increased by more than 80%. [Conclusion] Strain DC30-2-P1 from sugarcane leaf compost has a high efficiency on dissolving insoluble phosphorus compounds, promoting the absorption of phosphorus and improving crop yield.

Key words:phosphate-solubilizing fungus;Aspergillus awamori;phosphate-dissolving effect;growth-promoting effect