RNA interference technologies to protect crop plants

昆虫通常被认为是我们食物和纤维的最严重的竞争对手，通过对植物造成损害，繁殖植物病原体以及导致储存的食物，纤维和木制品腐烂来减少作物产量。据估计，昆虫消耗或破坏大多数国家国民生产总值的10%至20%，尽管我们努力控制最有害的害虫。大多数控制措施依赖于使用广谱合成杀虫剂来控制害虫。不幸的是，这些化学品不仅杀死害虫，还杀死非目标益虫，并可能对其他无脊椎动物和脊椎动物物种产生不利影响。本研究的主要目的是评估用于农业的新物种特异性农药，以减少对非目标物种的负面影响。将特别审查两种技术：RNA干扰和来自土壤细菌苏云金芽孢杆菌的杀虫蛋白（“Bt”蛋白）。RNAi是一种可以彻底改变害虫控制的新技术，因为它可以选择性地沉默害虫中的特定基因，而不会影响其他不共享确切基因序列的物种。由于每个物种都是由其遗传密码的独特性定义的，因此这项技术可以适用于控制不同种植系统中的许多不同害虫。几十年来，通过鉴定具有狭窄宿主特异性的细菌衍生的天然杀虫蛋白（从苏云金芽孢杆菌获得），Bt技术已被有效和安全地使用。Bt产品最初是作为叶面施用，但最近在过去的20年里，已经确定了选择性蛋白质，并用于转基因作物中，以选择性地杀死主要害虫。这些技术提供的植物虫害保护预计将增加作物产量，减少储存期间的损失，从而增加加拿大农民和农业的盈利能力。开发对环境更安全的方法来控制农业害虫也将使加拿大成为农业生物技术部门的领导者。

Insects are often considered our most serious competitors for food and fiber, reducing crop yields by inflicting damage to plants, propagating plant pathogens, and causing decay in stored food, fiber, and wood products. It has been estimated that insects consume or damage between 10 and 20% of the gross national products of most nations, despite our efforts to control the most noxious pests. Most control measures rely upon the use of broad-spectrum synthetic pesticides to control the pests. Unfortunately, these chemicals not only kill pests, but also kill non-target beneficial insects, and can adversely affect other invertebrate and vertebrate species. The primary objective of this research is to evaluate new species-specific pesticides for use in agriculture that may reduce negative impacts on non-target species. Two technologies in particular will be examined: RNA interference (RNAi) and insecticidal proteins derived from the soil bacterium Bacillus thuringiensis ("Bt" proteins). RNAi is a new technology that could revolutionize pest insect control, as it can selectively silence specific genes within the pests, but without affecting other species that do not share the exact gene sequences. As each species is defined by the uniqueness of its genetic code, this technology could be adapted to control many different pests in different cropping systems. Bt technology has been used effectively and safely for decades through the identification of bacterially-derived, natural insecticidal proteins with narrow host-specificities (obtained from Bacillus thuringiensis). Bt products were first used as foliar applications, but more recently during the past 20 years, select proteins have been identified and used in transgenic crops to selectively kill key insect pests. Plant protection from insect pests afforded by these technologies is expected to increase crop yields and reduce losses during storage, and consequently, increase profitability for Canada farmers and the agricultural industry. The development of environmentally-safer methods to controlling agricultural pests would also place Canada among the leaders in the agricultural biotechnology sector.