Using gene technology for improving crop morphology for protected environments

背景：气候变化、土壤侵蚀以及与田间病虫害化学防治相关的问题，促使人们对在受保护的环境以及室内农场等受控环境中种植选定作物产生了兴趣。垂直农场系统等完全受控的室内环境有很多好处：1)作物快速生长，2)减少水/养分/农药投入，3)减少食物距离。迄今为止，大多数商业上活跃的室内农场都专注于微型蔬菜或小叶沙拉作物，但有可能种植更多类型的作物。种植者现在热衷于开发高度控制的环境，作为田间种植作物的替代方案，以增加当地产量。然而，与田间种植的作物品种不同，开发适合这种环境的作物的研究或育种努力有限。尽管垂直农场中许多作物快速健康发展，但植物结构/建筑并未优化。几十年来，育种者已经选择了适合大田或温室栽培条件的品种基因型。迄今为止，针对不同室内栽培条件和其他受保护环境进行的集中育种/选择很少。通常，植物工厂采用两种主要设计风格之一：1)多层堆叠的水平生长平台；2)-垂直单元平行堆叠，层与层之间有LED照明。水平系统限制了作物的高度，而垂直系统更好地适应了更高的作物，在气培系统中对辣椒和黄瓜进行的初步研究导致了次优的作物结构，低效的扭曲茎和长掉落的果实。利用矮壮植株可显著改善作物栽培。挑战：育种或选择矮化表型的品种是一个漫长的过程，使用传统育种方法已经花了几十年的时间。为了应对在受保护环境中种植具有替代结构结构的作物的挑战，需要通过使用现代遗传改良策略进行快速创新。20世纪50年代至60年代的农业绿色革命带来了我们主要可耕地作物的矮品种，这导致了全球作物产量的增加。小麦矮化的基因是已知的，涉及植物激素赤霉素（GA）的产生。迄今为止，这种知识的应用仅限于田间种植作物的开发，从未用于商业园艺作物（特别是高辣椒和黄瓜家族）。我们将利用这些知识和最先进的基因组编辑（GE）技术，为气耕控制环境和受保护的温室生产矮辣椒和黄瓜。项目目标：利用CRISPR基因工程技术敲除辣椒、黄瓜中的GA基因，培育矮化植株。使用嫁接方法去除辣椒中的CRISPR元素。评估基因操作对植物表型的影响。在室内农场和商业温室中测试选定品系的生长/产量，以评估商业效益。这将是第一批使用CRISPR在受保护环境中操纵植物结构的研究之一。此外，这项技术和方法的发展有许多应用和好处：1)利用转基因技术开发具有适当形态和特征的植物的概念验证，以适应创新的室内生长环境；2)为在新的生长环境中改善植物表型提供了更广泛的应用范例；3)利用嫁接技术通过去除CRISPR标记来提高早期生长速度的工业潜力展示。这些因素共同为PACE作物的发展提供了重大进展。

Context: Climate change, soil erosion and issues associated with chemical control of pests/diseases under field conditions is driving interest in cultivating selected crops in protected environments as well as controlled environments such as indoor farms.There are many benefits associated with fully controlled indoor environments such as vertical farm systems: 1) rapid crop development, 2) reduced water/nutrient/pesticide inputs, and 3) reduced food miles.To date, most commercially-active indoor farms have focused on microgreens or baby leaf salad crops, but there is potential to grow more crop types. Growers are now keen to develop highly controlled environments as an alternative to field grown crops for increased local production. However, unlike field-grown crop varieties, there has been limited research or breeding efforts to develop crops for such environments.Despite fast, healthy development of many crops in vertical farms, plant structure/architecture is not optimised. Breeders have selected varietal genotypes for field or glasshouse cultivation conditions over many decades. As yet, very little focussed breeding/selection has been undertaken for different indoor cultivation conditions and other protected environments.Typically, plant factories employ one of two main design styles:1)-Layers of stacked horizontal growing platforms;2)-Vertical units stacked in parallel, with LED lighting between layers.Horizontal systems limit crop-height, and whilst vertical systems better accommodate taller crops, pilot studies with chillies and cucumbers in aeroponic systems resulted in sub-optimal crop architecture, with inefficient twisted stems and long dropping fruit. Crop cultivation could be significantly improved through use of bushier, dwarf plants.Challenges: Breeding or selecting cultivars with dwarf phenotypes is a lengthy process, which has taken decades using conventional breeding approaches. Meeting the challenge of growing crops with alternative structural architecture for protected environments requires rapid innovation via use of modern genetic improvement strategies. The agricultural Green Revolution of the 1950/60s delivered dwarf varieties of our major arable crops, which resulted in increased global crop yields. Genes responsible for dwarfing wheat plants are known and involve production of the plant hormone Gibberellic Acid (GA). To date, application of this knowledge is restricted to the development of field-grown crops, and has never been exploited for commercial horticultural crops (notably tall pepper and cucumber families).We will exploit this knowledge alongside state-of-the-art genome editing (GE) techniques to produce dwarf peppers and cucumbers for aeroponic controlled environments and protected glasshouses.Project objectives:Exploit CRISPR GE technology to knock-out GA genes in pepper and cucumber to produce dwarf plants.Use grafting approaches to remove CRISPR elements in peppers.Assess the impact of gene manipulation on plant phenotypes.Test selected lines for growth/yield in indoor farms and a commercial glasshouse to evaluate commercial benefits.This will be one of the first studies to use CRISPR to manipulate plant architecture for protected environments. Furthermore, development of the technology and approach has numerous applications and benefits: 1) Proof-of-concept for use of GE technology to develop plants with the appropriate morphologies and traits for innovative indoor growth environments; 2) Exemplar for a much wider range of applications to improve plant phenotypes for new growing environments; 3) Demonstration of industrial potential for the use of grafting techniques to increase early growth rate via removal of CRISPR markers. Together these provide significant advancements for developing PACE cropping.