Chin J Plan Ecolo ›› 2016, Vol. 40 ›› Issue (2): 140-150.DOI: 10.17521/cjpe.2015.1107

• Research Articles • Previous Articles     Next Articles

Effects of peach branches returning on autotoxins and microbes in soil and tree growth of peaches

Jiang-Hong ZHANG1, Fu-Tian PENG1,*(), Xiao-Mei JIANG1, Min-Ji LI1, Zhong-Tang WANG2   

  1. 1State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, China
    and
    2Shandong Institute of Pomology, Tai'an, Shandong 271018, China
  • Online:2016-02-10 Published:2016-03-08
  • Contact: Fu-Tian PENG

Abstract:

Aims This study aimed to investigate the effects of branch returning on the growth of peach (Amygdalus persica "Chunmei/Maotao") saplings, soil enzyme activity, and soil contents of phenolic acids and amygdalin, thereby providing scientific evidence against the application of branch returning for peach trees. Methods One-year-old potted peach tree (Amygdalus persica "Chunmei/Maotao") was used in this study with four agricultural treatments applied, including soil coverage by fragmented peach tree branches (fragment treatment;1.5 and 22.5 g·kg-1) and applying leachate solutions of peach tree branches to soil (leachate treatment; 1.5 and 22.5 g·kg-1). No branch addition was used as control (CK). Solid phase extraction, high performance liquid chromatography (HPLC), biological high-throughput sequencing was used to determine the content of autotoxic substances, and microbial community structure in soil. Soil coverage and leachate solution treatments of 30 g and 450 g branches applied to the peach trees were described as 1.5 and 22.5 g·kg-1, respectively in this paper.Important findings Compared with CK, the phenolic acid and amygdalin contents significantly increased after both fragment and leachate treatments in high quantities (22.5 g·kg-1). Soil microbial community structure altered in both treatments, with the proportion of fungi (particularly Agaricomycetes, Tubeufia and Cystofilobasidiaceae) increased significantly and bacteria decreased accordingly. Invertase activity in both high-quantity treatments exceeded that in the CK significantly. The activity of catalase and urease was higher at first and then decreased relative to CK under high-quantity fragment and leachate treatments. Specifically, the effect of leachate treatment on enzyme activity was higher than the fragment treatment in the short term. Chlorophyll content, ground diameter (diameter of 5 cm from the ground) growth and net photosynthesis rate of plants were lower in high-quantity fragment and leachate treatments than those in CK, with earlier retardation of new shoot growth. We observed an increase in soil phenolic acids and enzymes in treatments in normal pruning quantity, while no inhibition effect was found on the tree growth. In conclusion, autotoxins (such as phenolic acid and amygdalin) inhibited the growth of peach trees both directly and indirectly through changing soil enzyme activity and microbial community.

Key words: autotoxins, branch returning, microbial community, peach tree, plant growth