摘要
微生物法改良盐碱土是一种绿色可持续的方式,另一方面,刚果红毒性低、对酸碱度变色灵敏,是一种理想的酸指示剂,为快速降低盐碱土pH值从而为盐碱地植物存活提供必要条件,将刚果红作为培养基中的酸指示剂,从海边土壤筛选出一株耐高盐同时可高产有机酸的微生物SQ21,经形态学和ITS-rDNA鉴定确定其为一种黑曲霉。将SQ21单独应用于盐碱土改良,结果表明:土壤pH值下降程度与SQ21用量成正相关,当在500 g土壤中一次性施用3.18×1010cfu的SQ21孢子时,50天后可下降了pH2.24。将麦麸、复合肥或硝酸钠作为底肥施入500 g盐碱土中,且每隔两周施入7.96×109cfu SQ21孢子时,56天后土壤pH值分别下降了1.12、0.6和1.37个单位,继续比较被改良土壤上四季菊的生长情况,SQ21结合麦麸改良时四季菊的株高和冠幅增加幅度最大,综合评估土壤pH值下降幅度和四季菊生长情况,SQ21结合麦麸对盐碱土的改良效果优于其结合复合肥或硝酸钠。试验证明SQ21参与盐碱土改良时可显著降低土壤pH值和促进植物生长。
Saline-alkali soil improvement with microbe is a green and sustainable method,and Congo red is an ideal indicator with low toxicity and sensitive colour-changing ability to pH value.To reduce the soil pH value rapidly and provide essential foundation for the survival of plants,the Congo red was added into the culture medium to screen the strain with both well salt tolerance and high yield of organic acid,and finally the strain named SQ21 was successfully isolated from coastal saline soil,and was identified as Aspergillus niger after analyzing its morphological characters and ITS-rDNA sequence.After applying SQ21 into saline-alkali soil,the results showed that the soil pH value reducing degree was positively related to the dosage of SQ21,and after applying 3.18×10^10 cfu spores of SQ21 into 500 g saline-alkali soil,the soil pH value decreased by 2.24 after 50 days.After adding bran,compound fertilizer or sodium nitrate as base fertilizer into 500 g salinealkali soil,and applying 7.96×10^9 cfu spores of SQ21 into the soil every 2 weeks,the soil pH value of each treatments reduced by 1.12,0.6 and 1.37 after 56 days.The comparison of the growth of chrysanthemum on saline-alkali soil under different treatments showed that the height and crown diameter of chrysanthemum treated with SQ21 and bran increased the most,and the comprehensive evaluation of the pH value reducing degree and the growth of chrysanthemum indicated that the combination of SQ21 with bran was better than SQ21 with compound fertilizer or sodium nitrate.The research proved that the SQ21 could reduce the pH value of saline-alkali soil and promote plant growth.
作者
高鹏
王进
黄天悦
陈孝平
Gao Peng;Wang Jin;Huang Tianyue;Chen Xiaoping(School of Environmental Ecology and Biological Engineering,Wuhan Institute of Technology,Wuhan 430205)
出处
《中国农学通报》
2018年第35期72-78,共7页
Chinese Agricultural Science Bulletin
基金
国家自然科学基金(81172178)
关键词
盐碱土
改良
有机酸
黑曲霉
筛选
saline-alkali soil
improvement
organic acid
Aspergillus niger
screening
