中国农业科学 ›› 2024, Vol. 57 ›› Issue (1): 159-172.doi: 10.3864/j.issn.0578-1752.2024.01.011

• 园艺 • 上一篇    下一篇

接种土著和外源AM真菌对杜梨抗旱性的影响及其适应机制

栗晗1(), 江尚焘1, 彭海英1, 李培根1, 顾长宜1, 张金莲2, 陈廷速2, 徐阳春1, 沈其荣1, 董彩霞1()   

  1. 1 南京农业大学资源与环境科学学院,南京 210095
    2 广西农业科学院微生物研究所,南宁 530007
  • 收稿日期:2023-05-16 接受日期:2023-08-15 出版日期:2024-01-01 发布日期:2024-01-10
  • 通信作者:
    董彩霞,E-mail:
  • 联系方式: 栗晗,E-mail:1196139138@qq.com。
  • 基金资助:
    国家现代农业产业技术体系(CARS-28)

Effects of Inoculation with Indigenous and Exogenous Arbuscular Mycorrhizal Fungi on Drought Resistance of Pyrus betulaefolia and Its Adaptation Mechanism

LI Han1(), JIANG ShangTao1, PENG HaiYing1, LI PeiGen1, GU ChangYi1, ZHANG JinLian2, CHEN TingSu2, XU YangChun1, SHEN QiRong1, DONG CaiXia1()   

  1. 1 College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095
    2 Microbiology Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007
  • Received:2023-05-16 Accepted:2023-08-15 Published:2024-01-01 Online:2024-01-10

摘要:

【目的】丛枝菌根(AM)真菌可改善植物生长,提高抗环境胁迫能力。筛选对梨苗具有抵御干旱胁迫的AM真菌,为梨菌根化育苗提供理论依据与技术途径。【方法】采用盆栽试验及高通量测序技术,对杜梨苗分别接种梨土著AM真菌层状近明球囊霉(Claroideoglomus lamellosum,Cl)和外源菌株摩西斗管囊霉(Funneliformis mosseae,Fm)、根内根孢囊霉(Rhizophagus intraradices,Ri)及蜜色无梗囊霉(Acaulospora mellea,Am),探究干旱胁迫下单接种土著、外源菌株及混合接种(Mix)处理对杜梨幼苗生长的影响,分析干旱0、3和6周Mix处理下根系及根际土AM真菌群落变化。【结果】正常水分和干旱处理下,单接种梨土著菌株Cl、外源菌株Ri及Mix处理均显著提高株高、茎粗、叶面积、叶片相对含水量,干重增加35.26%—52.20%;地上部磷、钾、钙、镁等元素吸收增强,尤其增加磷的吸收,菌根磷吸收效应最高达1.0以上,而单接种外源菌株Am效果次之,正常供水条件下Fm抑制杜梨幼苗生长。回归性分析表明,菌根生长效应和元素吸收随侵染强度的增加而增加。干旱胁迫下,接种AM真菌显著降低杜梨幼苗叶片丙二醛含量,抗氧化酶活性和脯氨酸含量均有不同程度提高。测序结果显示,与正常水分相比,干旱胁迫下杜梨幼苗根系及根际土AM真菌群落结构发生显著改变,其中外源菌株Ri均占主导,Cl、Am丰度次之,Fm丰度最低,且随干旱胁迫程度增加,根内Ri的丰度显著上升。【结论】接种不同AM真菌对杜梨幼苗具有不同的生长效应,其中梨土著菌株Cl和外源菌株Ri表现出较强的促生和抗旱能力。AM真菌群落中Ri丰度的提高是杜梨幼苗适应干旱胁迫的重要途径。

关键词: 干旱胁迫, 杜梨, 丛枝菌根真菌, 促生, 群落结构

Abstract:

【Objective】Arbuscular mycorrhizal (AM) fungi play a significant role in enhancing plant growth and improving resistance to environmental stress. The aim of this study was to screen AM fungi that can withstand drought stress in pear seedlings, so as to establish a theoretical foundation and technical approach for pear mycorrhizal cultivation. 【Method】In this study, a pot experiment and high-throughput sequencing technology were employed to investigate the effects of single and mixed inoculation with indigenous AM fungi, including Claroideoglomus lamellosum (Cl), the exogenous fungus Funneliformis mosseae (Fm), Rhizophagus intraradices (Ri), and Acaulospora mellea (Am), on the growth of Pyrus betulaefolia seedlings under normal and drought conditions. The changes in the AM fungal community in the roots and rhizosphere soil of P. betulaefolia seedlings were analyzed under mixed inoculation (Mix) after 0, 3, and 6 weeks of drought treatment. 【Result】 Under normal and drought conditions, the single inoculation with Cl, Ri, and Mix significantly increased the plant height, stem diameter, leaf area, and relative water content of the leaves of pear seedlings, resulting in a dry weight increase of 35.26% to 52.20%. Additionally, the uptake of phosphorus, potassium, calcium, and magnesium in the aboveground part of the seedlings was enhanced, especially phosphorus uptake, with a mycorrhizal phosphorus uptake effect of up to 1.0. The exogenous fungus Am showed less effectiveness, while Fm inhibited the growth of P. betulaefolia seedlings under normal water supply conditions. Regression analysis indicated that the growth and element absorption effects of mycorrhizal fungi increased with the degree of infection. Under drought stress, AM fungal inoculation significantly reduced the MDA (malondialdehyde) content in the leaves of P. betulaefolia seedlings and increased the activity of antioxidant enzymes and the content of proline to varying degrees. Sequencing results demonstrated that the structure of the AM fungal community in the roots and rhizosphere soil of P. betulaefolia seedlings changed significantly under drought stress compared with normal water conditions. The exogenous fungus Ri dominated the community, followed by Cl and Am, while Fm was the least abundant. The abundance of Ri in the roots significantly increased with the degree of drought stress. 【Conclusion】In conclusion, the different AM fungi had varying effects on the growth of P. betulaefolia seedlings, with the indigenous strain Cl and the exogenous strain Ri showing strong growth-promoting effect and drought resistance. The increase in Ri abundance in the AM fungal community was an important adaptation mechanism for P. betulaefolia seedlings to withstand drought stress.

Key words: drought stress, Pyrus betulaefolia, arbuscular mycorrhizal fungi, growth-promoting, community structure