产紫蓝状菌解磷条件的优化及对辣椒生长与品质的影响

Optimization of culture conditions for phosphorus solubilization of Talaromyces purpureogenus with effects of promoting the growth and improving the quality of red cluster pepper

摘要:

目的 从玉米根际土壤中筛选出一株对磷酸三钙与植酸钙均有较好的解磷效果的解磷真菌——产紫篮状菌(Talaromyces purpureogenus)，并命名为XZY3PSF。为了后续将该菌株应用于农业生产，开展其解磷条件优化及对辣椒生长与品质影响的研究。方法 采用液体摇培法测定溶液中有效磷含量，研究该菌株对Ca₃(PO₄)₂、FePO₄、AlPO₄、磷矿粉、大豆卵磷脂及鸡蛋黄等6种难溶性磷酸盐的溶解能力，并探讨碳源、氮源、pH、装液量等因素对其解磷能力的影响；采用温室盆栽法评价该菌株对辣椒的促生作用及对果实品质的影响。结果 该菌株对碳源的利用顺序依次为果糖>葡萄糖>麦芽糖>蔗糖；对氮源的利用顺序依次为氯化铵>硝酸铵>硫酸铵>硝酸钾>脲。菌株在初始pH 6.0-7.0的条件下解磷能力较强，不同装液量对菌株的解磷能力无显著性影响。在供试的6种磷源培养液中，该菌株对磷酸三钙和磷矿粉的解磷量最高。其中，磷酸三钙在第5天达到最高解磷量，且极显著高于其他磷源(P<0.01)；磷矿粉则在第21天达到最高解磷量，且极显著高于其他磷源(P<0.01)。与施用复合化肥相比，该菌株可显著提高辣椒苗的株高、辣椒产量、辣椒维生素C含量与辣椒素类物质总量(P<0.05)。Pearson相关性分析结果表明，菌株XZY3PSF在不同氮源或不同碳源的培养液中的解磷量与pH变化呈极显著负相关关系，与菌丝干重呈显著或极显著负相关关系；辣椒素类物质含量与维生素C含量、糖度之间分别呈极显著与显著正相关关系。结论 菌株XZY3PSF解磷能力强，尤其对磷酸铝与磷酸铁类磷源也具有一定的解磷能力，能显著提高作物的主要营养指标，推测其在南方砖红土壤中将具有较强的解磷能力，为后续田间应用奠定良好基础。

关键词:产紫篮状菌;条件优化;辣椒;促生作用;品质

Abstract:

Objective A Talaromyces purpureogenus strain with solubilizing effects on tricalcium phosphate and calcium phytate was screened from the rhizosphere soil of maize and named XZY3PSF. To promote the application of this strain in serving agricultural production, we optimized the culture conditions for phosphorus solubilization of this strain and studied the effects of this strain on the growth and quality of red cluster pepper.Methods We evaluated the solubilizing effects of strain XZY3PSF on Ca₃(PO₄)₂, FePO₄, AlPO₄, phosphate rock powder, soybean lecithin, and egg yolk by measuring the available phosphorus content in the solution after liquid shaking culture. The effects of carbon source, nitrogen source, pH, and liquid loading volume on the phosphorus solubilization of this strain were studied. Pot experiments were carried out in a greenhouse to evaluate the effects of this strain on the growth and fruit quality of red cluster pepper.Results The carbon sources used by the strain were in an order of fructose>glucose>maltose>sucrose, and the nitrogen sources followed an order of ammonium chloride>ammonium nitrate>ammonium sulfate>potassium nitrate>urea. The phosphorus-solubilizing ability of the strain was higher under the condition of initial pH 6.0-7.0, and it was not affected by the liquid loading volume. The strain achieved higher phosphorus solubilization with tricalcium phosphate and phosphate rock powder as the phosphorus sources. With tricalcium phosphate as the phosphorus source, the strain showed the highest phosphorus solubilization on days 5, which was higher than that with other phosphorus sources (P<0.01). With phosphate rock powder as the phosphorus source, the strain showed the highest phosphorus solubilization on days 21 (P<0.01). Compared with the application of compound fertilizer, the inoculation of this strain increased the plant height, yield, vitamin C content, and total capsaicinoid content of red cluster pepper (P<0.05). The results of Pearson correlation analysis showed that the phosphorus solubilization of strain XZY3PSF in the culture medium with different nitrogen or carbon sources was negatively correlated with pH and the dry weight of mycelia. The capsaicinoid content was positively correlated with vitamin C and sugar content of pepper fruits.Conclusion Strain XZY3PSF has a strong ability to solubilize phosphorus, especially aluminum phosphate and iron phosphate, while improving the main nutritional indicators of crops. It is hypothesized that the strain will have a strong ability to solubilize phosphorus in the laterite soil in southern China. These findings lay a foundation for subsequent application of this strain in the fieled.

Key words:Talaromyces purpureogenus;condition optimization;red cluster pepper;plant growth-promoting effects;quality