不同施肥处理对‘赤霞珠’葡萄根际土壤养分和真菌群落的影响

Different fertilization treatments affect rhizosphere soil nutrients and fungal communities of ‘Cabernet Sauvignon’ grapes

摘要:

【背景】宁夏贺兰山东麓葡萄产区忽视有机肥的施用，果树枝条焚烧污染环境，造成土壤养分缺失，土壤质量下降。【目的】为解决长期施用化肥对土壤造成的一系列问题，通过大田试验研究施肥及喷施不同浓度菌剂对土壤理化性质、真菌群落组成及多样性的影响，为酿酒葡萄可持续健康发展提供科学依据。【方法】以‘赤霞珠’葡萄根际土壤为试验对象，采用Illumina MiSeq高通量测序技术，测定并分析根际土壤理化性质、真菌群落组成和多样性在7个处理[常规施肥(CK)、蚯蚓粪+腐熟枝条+100倍菌剂(T1)、蚯蚓粪+腐熟枝条+200倍菌剂(T2)、蚯蚓粪+腐熟枝条+300倍菌剂(T3)、蚯蚓粪+未腐熟枝条+100倍菌剂(A1)、蚯蚓粪+未腐熟枝条+200倍菌剂(A2)和蚯蚓粪+未腐熟枝条+300倍菌剂(A3)]的变化。【结果】相较于CK，葡萄根际土壤理化性质差异明显，施肥处理增加了土壤有机质含量，土壤pH含量无明显变化，改良了土壤结构，活化了土壤有效养分。相较于CK，各处理真菌分类操作单元(operational taxonomic unit, OTU)数均降低，A2处理根际土壤丰富度及多样性均显著增加。真菌群落组成结果显示，门水平下子囊菌门(Ascomycota)、担子菌门(Basidiomycota)、壶菌门(Chytridiomycota)和被孢霉门(Mortierellomycota)均为7个处理的优势菌，占总相对丰度的74.40%-86.97%。T2、A2处理产量分别显著提高19.34%、14.72%。相关性分析表明，各处理全氮含量是影响真菌群落结构的主要因素，微生物与产量无显著关系，电导率、全氮是与产量密切相关的因子。【结论】T2、A2处理改善了土壤微生物群落结构，提高了土壤养分，进而促进葡萄生长，并提高产量和生产效益，为葡萄选择适合的施肥方式提供了一定理论依据。

Abstract:

[Background] The grape production in eastern Helan Mountains has the problems of poor soil nutrients, neglect of organic fertilizer application, and environmental pollution caused by the burning of fruit plant branches. [Objective] In view of the problems caused by long-term application of chemical fertilizers to the soil, we carried out field experiments to study the effects of fertilizer application and fungicide spraying on the soil physicochemical properties and the fungal community composition and diversity, aiming to underpin the sustainable and healthy development of wine grapes. [Methods] The physicochemical properties of the rhizosphere soil of ‘Cabernet Sauvignon’ were examined. Illumina MiSeq high-throughput sequencing was performed to determine the fungal community composition and diversity in the rhizosphere soils in seven treatments: conventional fertilization (CK), earthworm manure+fermented branches+100×fungicide (T1), earthworm manure+fermented branches+ 200×fungicide (T2), earthworm manure+fermented branches+300×fungicide (T3), earthworm manure+unfermented branches+100×fungicide (A1), earthworm manure+unfermented branches+200×fungicide (A2), and earthworm manure+unfermented branches+300×fungicide (A3). [Results] Compared with CK, other treatments significantly changed the chemical properties of the rhizosphere soil. Specifically, the fertilization treatments increased the organic matter, did not alter the soil pH, improved the soil structure, and activated the available nutrients in soil. Compared with CK, The number of fungal operational taxonomic unit (OTU) decreased in all treatments, and A2 treatment increased the fungal richness and diversity in the rhizosphere soil. Ascomycota, Basidiomycota, Chytridiomycota, and Mortierellomycota were dominant in all the seven treatments at the phylum level, accounting for 74.40%–86.97% of the total relative abundance. T2 and A2 treatments increased the grape yield by 19.34% and 14.72%, respectively. The correlation analysis showed that total nitrogen was the main factor affecting the fungal community structure; microorganisms were not significantly related to yield; electric conductivity and total nitrogen were factors closely associated with yield. [Conclusion] T2 and A2 treatments improved the soil microbial community structure and soil nutrients, which promoted grape growth and improved yield and production efficiency, providing a theoretical basis for the selection of suitable fertilization schemes for grapes.