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Acta Agron Sin ›› 2017, Vol. 43 ›› Issue (02): 286-295.doi: 10.3724/SP.J.1006.2017.00286

• TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY • Previous Articles     Next Articles

Influence of Long-term Fertilizations on Nutrients and Fungal Communities in Typical Paddy Soil of South China

CHEN Dan-Mei1,YUAN Ling1,*,HUANG Jian-Guo1,JI Jian-Hua2,HOU Hong-Qian2,LIU Yi-Ren2,*   

  1. 1College of Resources and Environment, Southwest University, Chongqing 400716, China; 2Soil and Fertilizer and Resources and Environment Institute, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China
  • Received:2015-12-08 Revised:2016-09-18 Online:2017-02-12 Published:2016-09-27
  • Contact: 袁玲, E-mail: lingyuanh@aliyun.com; 刘益仁, E-mail: jxnclyr@163.com E-mail:544328279@qq.com
  • Supported by:

    This study was supported by the National Natural Science Foundation of China (31460544), the Doctoral Scientific Research Foundation of Jiangxi Academy of Agricultural Sciences (2012CBS011), the National Support Program of China (2012BAD05B05), and the China Special Fund for Agro-scientific Research in the Public Interest (201203030).

Abstract:

 

A long-term field experiment was carried out for 31 years in Jiangxi Academy of Agricultural Sciences with a typical paddy soil in South China to study the influence of fertilizer application on changes of soil nutrients and fungal communities by rational analysis and 454 high-throughput sequencing technology. The fertilization treatments included control (without fertilizer), sole chemical fertilizer, 70% chemical fertilizer in combination with 30% organic fertilizer, 50% chemical fertilizer in combination with 50% organic fertilizer and 30% chemical fertilizer in combination with 70% organic fertilizer. The soil pH decreased in the treatment of sole chemical fertilizer, but increased obviously with the proportion of organic fertilizer increased. Organic-inorganic fertilizations significantly increased organic matter, available nitrogen and phosphorus, and microbial biomass carbon and nitrogen in the soil. The number of soil fungal 18S rDNA sequences was doubled while the species number of fungi decreased by 11-40 when received chemical fertilizer only, compared with the treatment of organic-inorganic fertilization. The top 20 predominant fungi ranged from 78.82% to 91.51% of the total in soil, and among them 7-13 species attributed to Ascomycetes which was the largest soil fungal group and accounted for 23.13%-75.09% of the top 20 predominant fungi. Compared with the control, 14-15 of the same species of dominant fungi were found in the treatment of organic-inorganic fertilizers but only nine in the treatment of sole chemical fertilizer. Principal component analysis showed the significant difference in soil fungal community compositions between treatment of sole chemical fertilizer and others. In general, sole application of chemical fertilizer results in soil acidification, and exponential increment of soil fungi, but significant reduction in their species, richness and diversity indexes, suggesting the great changes in fungal community composition and the risk of over production of pathogen fungi in the soil. On the contrary, organic-inorganic fertilization treatment is beneficial to maintain the healthy ecological environment of paddy soil and the diversity of soil fungal communities.

Key words: Long-term fertilization, Rice, Soil nutrients, Fungus

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