Arable - Are chitin amendments to soil a means to control potato cyst nematodes?

耕地 - 土壤中的几丁质改良剂是否可以控制马铃薯胞囊线虫？

• 批准号: BB/X011984/1
• 负责人: James Price
• 金额: $ 6.37万
• 依托单位: James Hutton Institute
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FX011984%2F1
• 关键词: Arable; chitin; amendments; soil; means

Summary:Plant parasitic nematodes cause an estimated $80 billion of annual damage to global agriculture and threaten food security in many regions. The potato cyst nematode (PCN) is a plant parasitic nematode that infects solanaceous species and causes significant damage, primarily to potato crops. In the UK alone, PCN causes more than £31 million in damage annually. Historically, PCN has been managed by using nematicides. However, due to potential environmental concerns, these chemicals have become tightly regulated. Currently there is only one granular nematicide left on the UK market and this has an uncertain future with an upcoming regulation review in 2024. Scotland is a large producer and exporter of seed potatoes. Current regulations state that if PCN has been detected in a field, that field can no longer be used for seed potato production. PCN is spreading in seed growing areas and recent predictions suggest that without improved PCN management tools this industry will collapse by 2050.Chitin is an abundant biomolecule which is found in insects, fungi and shellfish. Chitin is also present in PCN eggshells where it protects the developing juvenile by providing the eggshell with rigidity and tensile strength. Chitinous soil amendments have previously been proposed for control of plant parasitic nematodes. Addition of chitin to soils may help select for chitin-degrading microbial populations, naturally raising the prevalence of these organisms in that environment. The microbes may subsequently use sources of chitin already present in the soil, such as PCN eggshells, as an energy source, allowing the suppression of PCN numbers to a level where they are no longer a threat to the potato crop.We currently do not know if chitinous soil amendments are suitable for Scottish growing conditions or the impact they have on beneficial, chitin-containing, soil organisms. In this work we will investigate whether chitinous soil amendments control PCN in UK soils and how this control is achieved. Soil samples from field plots treated either with or without chitinous soil amendments will be collected. These samples will be used to identify the presence of different fungal, bacterial and free-living nematode populations and to quantify PCN numbers and chitin degrading activity. Comparing treated and untreated samples will allow understanding of changes in PCN populations, which microorganisms are responsible and if there is a negative impact on wider soil biodiversity. Testing in a controlled greenhouse environment will confirm whether the chitin within the soil amendment has a positive effect towards reducing PCN populations through eggshell degradation and will confirm which microorganisms are responsible.The project outcomes will include identifying differences in microbial and nematode populations in field samples treated with or without a chitin-rich soil amendment. Analysis of the increased presence of chitinase, the enzyme responsible for chitin degradation, in soil samples will confirm the pathway utilised to degrade PCN eggshells. Additionally, structural investigation of PCN eggshells will validate whether eggshells are degraded sufficiently to prevent PCN hatching. Populations of potentially beneficial free-living nematodes will be identified in treated and untreated samples to survey for potential wider nematocidal effects of chitin-based soil amendments.

摘要：植物寄生线虫每年对全球农业造成约 800 亿美元的损失，并威胁许多地区的粮食安全。马铃薯胞囊线虫 (PCN) 是一种植物寄生线虫，可感染茄科物种并造成重大损害，主要是对马铃薯作物。仅在英国，多氯化萘每年就会造成超过 3100 万英镑的损失。历史上，多氯化萘是通过使用杀线虫剂来管理的，但是，由于潜在的环境问题，这些化学品已成为潜在的威胁。目前，英国市场上只剩下一种粒状杀线虫剂，而且随着 2024 年即将进行的监管审查，该杀线虫剂的未来前景不明。苏格兰是马铃薯种薯的主要生产国和出口国，目前的法规规定，如果在马铃薯种薯中检测到多氯化萘，则该种杀线虫剂的未来将面临不确定性。无法再用于马铃薯种薯生产的田地正在种子种植区蔓延，最近的预测表明，如果不改进 PCN 管理工具，该行业将在 2050 年崩溃。甲壳质是一种丰富的生物分子。甲壳素也存在于昆虫、真菌和贝类中，通过为蛋壳提供刚性和拉伸强度来保护发育中的幼体，此前已提出使用甲壳素土壤改良剂来控制植物寄生线虫。帮助选择几丁质降解微生物种群，自然地提高这些微生物在该环境中的流行率。这些微生物随后可能会使用土壤中已有的几丁质来源，例如多氯化萘。蛋壳作为一种能源，可以将 PCN 数量抑制到不再对马铃薯作物构成威胁的水平。我们目前不知道几丁质土壤改良剂是否适合苏格兰的生长条件，也不知道它们对有益的影响在这项工作中，我们将研究几丁质土壤改良剂是否控制英国土壤中的多氯化萘，以及如何从经过或不经过几丁质土壤改良剂处理的田间收集这些样品。将用于识别不同真菌、细菌和自由生活线虫种群的存在，并量化 PCN 数量和几丁质降解活性，比较处理和未处理的样品将有助于了解 PCN 种群的变化、哪些微生物负责以及是否存在变化。对更广泛的土壤生物多样性产生负面影响。在受控温室环境中进行的测试将确认土壤改良剂中的甲壳素是否对通过蛋壳降解减少 PCN 种群产生积极影响，并将确认是哪些微生物造成的。项目成果将包括识别经过或未经过富含几丁质土壤改良剂处理的田间样品中微生物和线虫种群的差异，对土壤样品中几丁质酶（负责几丁质降解的酶）存在的增加进行分析，将确认用于降解 PCN 蛋壳的途径。此外，对 PCN 蛋壳的结构研究将验证蛋壳是否充分降解以防止 PCN 孵化，并将在经过处理和未经处理的样品中鉴定出潜在有益的自由生活线虫种群。基于甲壳素的土壤改良剂可能具有更广泛的杀线虫作用。