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Acta Agron Sin ›› 2016, Vol. 42 ›› Issue (07): 1037-1046.doi: 10.3724/SP.J.1006.2016.01037

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

Effects of Cotton Straw Returning on Soil Available Nutrients and Microbial Characteristics

LIU Yan-Hui1,WANG Shuang-Lei1,2,LI Jin-Pu1,3,QIN Du-Lin1,ZHANG Mei-Ling1,NIE Jun-Jun1,MAO Li-Li1,SONG Xian-Liang1,*,SUN Xue-Zhen1,*?   

  1. 1 State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Tai’an 271018, China; 2 Yantai Agricultural Technology Extension Service, Yantai 264000, China; 3 Pingdingshan Seed Service Center, Pingdingshan 467000, China
  • Received:2015-11-17 Revised:2016-05-09 Online:2016-07-12 Published:2016-05-12
  • Contact: 孙学振, E-mail: sunxz@sdau.edu.cn; 宋宪亮, E-mail: xlsong@sdau.edu.cn E-mail:yanhuiliusdau@163.com
  • Supported by:

    The study is supported by Key Projects in National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (2013BAD05B06), Modern Agro-industry Technology Research System (SDAIT-03-05, SDAIT-03-05), Shandong Program for Improved Varieties of Agriculture (2013LZ, 2014LZ), and Natural Science Fund of Shandong Province (ZR2013CM005).

Abstract:

The experiment with two treatments of cotton straw returning and no straw returning was conducted using Denong 09068 at the Experimental Station of Shandong Agricultural University (Dezhou) to investigate the contents of soil available nutrients and microbial characters under cotton straw returning for four consecutive years. The main results indicated that compared with control (no straw returning), cotton straw returning significantly increased the contents of soil organic matter, alkaline hydrolyzed nitrogen, available potassium, soil microbial C and active microbial biomass by 8.16%, 13.23%, 12.30%, 13.63%, and 11.57% (0–20 cm soil layer), 6.08%, 27.51%, 11.47%, 14.32%, and 15.03% (20–40 cm soil layer), 6.05%, 12.87%, 8.08%, 10.60%, and 20.30% (40–60 cm soil layer) on average, respectively. Soil basal respiration rate of straw returning treatment was 13.14% and 17.44% in 0–20 cm and 20–40 cm soil layers respectively higher than that of no straw returning treatment, while no significant increase in 40–60 cm soil layer. Cotton straw returning significantly increased seed cotton yield (16.86%) and lint yield (15.03%), absolutely owning to larger total boll number (5.99%) and boll weight (10.25%), but there was no change in lint percentage, compared with no cotton straw returning treatment. Returning cotton straw can increase soil fertility, while applying appropriate P fertilizer and controlling obstacles in continuous cropping are necessary for long–term straw returning to enhance yield.

Key words: Cotton, Straw returning soil, Available nutrients contents, Microbial characters, Yield

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