A biopesticidal lease of life for crop protection : additive manufacturing for tailored timing of biopesticide release by natural triggers

在满足日益增长的粮食需求的同时，更可持续地种植作物是一项重大的全球挑战。为了实现更可持续的作物生产，迫切需要减少农场对合成化学农药的依赖，因为这些农药已导致土壤贫瘠、普遍的病虫害抗性、水污染和生物多样性的重大损失。在英国，目前大约有2,400种基于合成化学的授权植物保护产品（PPP），但可持续的选择要少得多，例如生物农药，抑制农作物害虫传播的天然微生物。在后者中，只有一小部分被允许用于可耕地作物。缺乏有效的替代选择意味着种植者目前无法满足消费者、环保机构和政策制定者对更可持续农业方法的需求。现有生物农药的不良功效加剧了这一问题。其效力差的一个根本原因是生物农药通常不能在环境中保持必要的浓度合适的时间。因此，在最需要它们的时候，它们可能不再活跃，因为害虫激增;农民试图通过持续的作物监测来确定它们的部署时间是不可行的。该项目将建立一个跨学科社区来解决这一问题。该项目的及时性是明确的：如果我们要改变我们的耕作习惯，以帮助创造更健康的土壤，更清洁的水和更安全，更可持续的农业，我们需要采取行动，为种植者提供正确的工具来实现这一目标。为了提供这样的工具，我们将引入增材制造能力，通过类似于生物医学中3D打印“多药丸”的概念来设计生物杀虫真菌孢子的封装和递送。也就是说，控制害虫的生物体将被并入聚合物“胶囊”中，并且它们的释放由与发出害虫生长信号的环境触发器完全相同的环境触发器控制和驱动-控制生物体将与害虫同时出现，引起及时的生物竞争，在此期间生物农药可以最佳地起作用并且植物生长可以茁壮成长。为了验证该项目的概念，我们将专注于使用水分和pH触发器（每种触发器都是与害虫增殖相一致的常见指标）从制造的胶囊中释放真菌，使用选定的代表对重要害虫（如孢囊线虫）具有生物农药潜力的真菌进行测试（这是英国和全球可耕地作物重大损失的原因）。我们的技术工作将提供真菌孢子封装和环境触发释放的优化，以及释放前和释放后真菌活力和生长的生物测定。这项工作将通过与主要行业合作伙伴和利益攸关方的密切合作来补充，以指导拟议技术的应用。这些研究人员由来自学术和非学术组织的科学家组成，他们的专业知识包括真菌生物学，增材制造和生物农药。该项目的积极进展将使主要参与者和受益者围绕生物农药胶囊的开发以及减缓或扭转害虫造成的作物生产恶化的共同使命的重点得到明确。

The need to meet the increasing demand for food while growing crops more sustainably is a major global challenge. For more sustainable crop production, there is an urgent need to reduce reliance on synthetic chemical pesticides on farms, as these have led to impoverished soils, widespread pest and disease resistance, water contamination and a significant loss of biodiversity. In the UK, there are presently around 2,400 authorised plant protection products (PPPs) based on synthetic chemistry, but far fewer sustainable options such as biopesticides, e.g., naturally occurring microorganisms that inhibit spread of crop pests. Of the latter, only a small handful are permitted on arable crops. This absence of effective, alternative options means growers are presently unable to meet demands from consumers, environmental bodies and policy makers, for a more sustainable approach to farming. This is exacerbated by poor efficacy of existing biopesticides. One fundamental reason for their poor efficacy is that biospesticides generally do not maintain the necessary concentrations in the environment for suitable amounts of time. Therefore, they may no longer be active when they are most needed, as pests proliferate; and it is not feasible for farmers to try to time their deployment through ongoing crop monitoring. This project will establish an interdisciplinary community to redress this problem. The timeliness for the project is clear: if we are to change our farming habits to help create healthier soils, cleaner water and safer, more sustainable farming we need action to give growers the correct tools to make it happen. To provide such tools, we will introduce additive-manufacturing capability to engineer the encapsulation and delivery of biopesticidal fungal spores via concepts similar to those used for 3D printed 'polypills' in biomedicine. That is, the pest controlling organisms will be incorporated into polymeric 'capsules' and their release controlled and driven by the very same environmental triggers as those that signal the growth of the pests - the controlling organisms would emerge at the same time as the pests, giving rise to a timely biological competition during which the biopesticide can act optimally and plant growth can thrive. For proof-of-concept in this project, we will focus on fungal release from manufactured capsules using moisture and pH triggers (each of which is a common indicator coincident with pest proliferation), tested using selected fungi representative of a range having biopesticidal potential against important pests such as cyst nematodes (which are responsible for significant losses of arable crops in the UK and globally). Our technical work will deliver optimisation of fungal-spore encapsulation and environmentally-triggered release in conjunction with biological assay of fungal viability and outgrowth pre- and post-release. This work will be complemented by close engagement with key industry partners and stakeholders to guide development towards application of the proposed technology. The investigators comprise a new, inter-disciplinary collaboration of scientists based at academic and non-academic organizations, with expertise encompassing fungal biology, additive manufacturing and biopesticides. Positive progress in this project will crystallize the focus of a community of key players and beneficiaries around development of the biopesticidal capsules and the common mission to slow or reverse the deterioration of our crop production by pests.