Xu Lingjie, Niu Xiaoyun, Li Xia, Zheng Yanyan, Feng Hualei, Fu Qiang, Zhou Yong
Country College of Landscape Architecture and Tourism, Hebei Agricultural University, Baoding, China.
School of Life Sciences, Hebei University, Baoding, China.
Front Microbiol. 2022 Oct 19;13:1013023. doi: 10.3389/fmicb.2022.1013023. eCollection 2022.
Nitrogen (N) availability is significant in different ecosystems, but the response of forest plant-microbial symbionts to global N deposition remains largely unexplored. In this study, the effects of different N concentration levels on four types of fungi, (Sg), (Pt), (Po), and sp. (Ps), isolated from the roots of were investigated . Then, the effects of the fungi on the growth performance, nutrient uptake, and rhizosphere soil microbial community structure of . under different N addition conditions (0, 40, and 80 kg hm year) were examined. The biomass and phytohormone contents of the Sg, Pt and Po strains increased with increasing N concentration, while those of the Ps strain first increased and then decreased. All four fungal strains could effectively colonize the plant roots and form a strain-dependent symbiosis with . . Although the effects depended on the fungal species, the growth and root development of inoculated seedlings were higher than those of uninoculated seedlings under N deficiency and normal N supply conditions. However, these positive effects disappeared and even became negative under high N supply conditions. The inoculation of the four fungal strains also showed significant positive effects on the shoot and root nutrient contents of . . Fungal inoculation significantly increased different microbial groups and the total soil microorganisms but decreased the microbial diversity under N deficiency stress. In summary, exogenous symbiotic fungal inoculations could increase the growth performance of . under N deficiency and normal N supply conditions, but the effects were negative under excessive N addition.
氮（N）的有效性在不同生态系统中具有重要意义，但森林植物 - 微生物共生体对全球氮沉降的响应在很大程度上仍未得到充分研究。在本研究中，研究了不同氮浓度水平对从[植物名称]根系分离出的四种真菌，即[真菌名称1]（Sg）、[真菌名称2]（Pt）、[真菌名称3]（Po）和[真菌名称4]属（Ps）的影响。然后，研究了这些真菌在不同氮添加条件（0、40和80 kg hm⁻² 年）下对[植物名称]的生长性能、养分吸收和根际土壤微生物群落结构的影响。Sg、Pt和Po菌株的生物量和植物激素含量随氮浓度增加而增加，而Ps菌株的生物量和植物激素含量先增加后降低。所有四种真菌菌株都能有效地定殖在植物根系上，并与[植物名称]形成菌株依赖性共生关系。尽管影响取决于真菌种类，但在氮缺乏和正常氮供应条件下，接种幼苗的生长和根系发育高于未接种幼苗。然而，在高氮供应条件下，这些积极影响消失甚至变为负面影响。接种这四种真菌菌株对[植物名称]的地上部和根部养分含量也显示出显著的积极影响。在氮缺乏胁迫下，真菌接种显著增加了不同微生物类群和土壤微生物总数，但降低了微生物多样性。总之，外源共生真菌接种在氮缺乏和正常氮供应条件下可提高[植物名称]的生长性能，但在过量施氮条件下效果为负。
