The self-regulatory potential of agro-ecosystems: Using nematodes as indicators for legume disease suppressive soils

农业生态系统的自我调节潜力：使用线虫作为豆科植物病害抑制土壤的指标

• 批准号: 420414676
• 负责人: Dr. Jan Henrik Schmidt
• 金额: --
• 依托单位: Institut für Pflanzenbau und Bodenkunde
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/420414676?language=en
• 关键词: self; regulatory; potential; agro; ecosystems

The susceptibility of legumes to root-rot diseases has massively contributed to the decline of their production area in Europe since 1974. This affects the biological nitrogen fixation as well as the overall sustainability of agroecosystems. As pesticides are of limited use to control soil-borne diseases, in the long term the build-up and maintenance of disease suppressive soils is much more promising. For the development of sustainable agricultural systems, there is a need to identify means by which to increase disease suppressiveness on the long run. Furthermore, robust and easy-to-apply indicators for disease suppressiveness of soils need to be identified.In two long-term experiments of the University of Kassel (since 2010 and 2011), soil suppressiveness to root-rot pathogens of pea was increased already after four years of minimum tillage (<12 cm depth) combined with compost fertilization compared to plough tillage (25-30 cm) combined with mineral potassium and phosphorous fertilization. In addition, specific cover crops suppressed plant-parasitic nematodes. Furthermore, free-living nematodes, which play an important role in disease suppression, were increased by minimum tillage. However, little is known about the use of free-living nematode trophic groups as indicators for disease suppressiveness of soils. Five years after these initial results, the long-term experiments at the University of Kassel are an important resource to investigate the development and stability of disease suppressiveness of soils as well as the role of free-living nematodes in disease suppression. We hypothesize that1. Specific nematode functional groups are linked with disease suppressiveness of soils;2. Minimum tillage and compost enhance disease suppressiveness of soils3. Cover crops foster specific nematode functional groups and thus, soil disease suppressiveness.In work package 1 (WP1), free-living nematodes will be identified and quantified in four differently managed soils of the long-term experiments applying morphological and molecular (NGS/OTUs) methods. Species composition and abundance will be related to nutrient contents as well as microbial biomass and activity of the respective soils. In a greenhouse experiment (WP2), specific suppressiveness of the soils against the plant-parasitic nematode Pratylenchus penetrans will be tested on peas and linked with abundances of nematode functional groups that were identified in WP1. In WP3, soils will be tested for their general suppressiveness against soil-borne fungal pea pathogens while the effects of cover crops on nematode taxa associated with disease suppression (WP1-3) will be determined via qPCR in WP4. Interrelationships of soil management histories, physico-chemical soil properties, specific and general suppressiveness, and nematode functional groups will be analysed using multivariate statistical approaches in order to obtain new and easy-to-apply indicators for disease suppressive soils.

自1974年以来，豆类对根 - 根疾病的敏感性大大促进了其在欧洲生产区域的下降。这影响了生物氮的固定以及农业生态系统的整体可持续性。由于农药在控制土壤传播疾病方面的用途有限，因此，从长远来看，抑制性土壤的积累和维持更加有前途。为了发展可持续农业系统，有必要确定从长远来看增加疾病抑制性的方法。此外，需要确定可识别土壤抑制性疾病的坚固且易于应用的指标。​​在卡塞尔大学的两种长期实验中（自2010年和2011年以来），土壤对PEA的根 - 茎病原体的抑制性已经增加了，在四年的最小耕作（<12 cm深度）与堆肥结合了培养基（<12 cm的深度）后，与plat pot量相比（25-30 cm相比）受精。此外，特定的覆盖作物抑制了植物寄生虫线虫。此外，在疾病抑制中起重要作用的自由生活线虫通过最少的耕作增加了。但是，对于使用自由线虫营养基团作为土壤抑制性的指标，知之甚少。这些初步结果五年后，卡塞尔大学的长期实验是研究土壤抑制性疾病的发展和稳定性以及自由生活线虫在疾病抑制中的作用的重要资源。我们假设1。特定的线虫官能团与土壤的疾病抑制性有关； 2。最低耕作和堆肥可以增强土壤的抑制性3。覆盖作物促进了特定的线虫官能团，因此，在工作包1（WP1）中，将在四个不同管理的土壤中鉴定和量化自由生活的线虫，用于采用形态学和分子（NGS/OTUS）方法的长期实验的四个不同管理的土壤。物种组成和丰度将与各种土壤的营养含量以及微生物生物量和活性有关。在温室实验（WP2）中，将在豌豆上测试土壤对植物性线虫pratylenchus pratylenchus pratylenchus pratylenchus pratylenchus pratylenchus的特异性抑制性，并与WP1中鉴定出的线虫官能团有关。在WP3中，将测试土壤对土壤传播真菌豌豆病原体的普遍抑制性，而覆盖作物对与疾病抑制相关的线虫类群的影响（WP1-3）将通过WP4中的QPCR确定。将使用多元统计方法分析土壤管理历史，物理化学土壤特性，特异性和一般抑制性以及线虫官能团的相互关系，以获取疾病抑制土壤的新指标。