Data from: Organic farming increases richness of fungal taxa in the wheat phyllosphere

Organic farming is often advocated as an approach to mitigate biodiversity loss on agricultural land. The phyllosphere provides a habitat for diverse fungal communities that are important for plant health and productivity. However, it is still unknown how organic farming affects the diversity of phyllosphere fungi in major crops. We sampled wheat leaves from 22 organically and conventionally cultivated fields in Sweden, paired based on their geographical location and wheat cultivar. Fungal communities were described using amplicon sequencing and real-time PCR. Species richness was higher on wheat leaves from organically managed fields, with a mean of 54 OTUs compared with 40 OTUs for conventionally managed fields. The main components of the fungal community were similar throughout the 350 km long sampling area and seven operational taxonomic units (OTUs) were present in all fields: Zymoseptoria, Dioszegia fristingensis, Cladosporium, Dioszegia hungarica, Cryptococcus, Ascochyta and Dioszegia. Fungal abundance was highly variable between fields, 103-105 internal transcribed spacer (ITS) copies per ng wheat DNA, but did not differ between cropping systems. Further analyses showed that weed biomass was the strongest explanatory variable for fungal community composition and OTU richness. These findings help provide a more comprehensive understanding of the effect of organic farming on the diversity of organism groups in different habitats within the agroecosystem.

有机农业常被倡导为缓解农业用地生物多样性流失的有效策略。叶围（phyllosphere）为多样的真菌群落提供了栖息生境，这类群落对植物健康与生产性能至关重要。然而，目前仍不清楚有机农业如何影响主栽作物的叶围真菌多样性。本研究从瑞典22对有机与常规种植农田中采集小麦叶片，每对农田均基于地理位置与小麦品种进行匹配。研究采用扩增子测序与实时定量PCR对真菌群落进行解析。结果显示，有机管理农田的小麦叶片物种丰富度更高，平均可达54个操作分类单元（operational taxonomic units，OTU），而常规管理农田的平均丰富度为40个OTU。真菌群落的核心类群在长达350公里的采样区域内均保持相似，且所有农田中均存在7个操作分类单元（OTU）：Zymoseptoria、Dioszegia fristingensis、Cladosporium、Dioszegia hungarica、Cryptococcus、Ascochyta以及Dioszegia。各农田间的真菌丰度差异显著，范围为每纳克小麦DNA中含有10³至10⁵个内转录间隔区（internal transcribed spacer，ITS）拷贝数，但两种种植系统间的真菌丰度并无显著差异。进一步分析表明，杂草生物量是解释真菌群落组成与操作分类单元丰富度的最强影响因子。本研究结果有助于更全面地阐明有机农业对农业生态系统内不同生境中生物类群多样性的影响。