Interactive effects of key components of global climate change on plant growth and development

探索植物对多种共生环境因素的反应对于更好地理解这些因素如何影响未来的植物生产和种子发育至关重要。尽管自然界中的植物受到多种因素的影响，但大多数研究一次只考虑一个因素。这项研究计划的总体目标是调查植物对与气候变化相关的多种环境因素的潜在反应机制。我们假设植物在营养和生殖阶段对单一和相互作用的环境因素的反应不同，脱落酸(ABA)是一个关键的内源因子，它作为一个重要的信号分子使植物对不断变化的环境产生保护反应。我们使用了来自十字花科的三种植物：油菜、臭草和拟南芥。油菜籽是加拿大一种重要的农业作物。关于它如何应对不断变化的环境的信息对加拿大农业来说很重要。杂草生长动态的变化对农业也很重要，因为杂草的侵略性生长会降低粮食作物的产量。臭草之所以被选中，是因为它在新斯科舍省的广泛分布和当地存在。拟南芥之所以被选中，是因为它对单一胁迫因子的反应是众所周知的，而且大量具有良好特征的突变体对ABA的反应不同。基于突变的方法使我们能够专注于生化、生理或解剖学水平上的特定问题，并从机制上理解这一过程。本研究的目的是：(1)研究CO2、温度和水分对营养生长期和生殖生长期植物生长发育的单一和交互作用；(2)阐明这些环境因子对植物生殖产量的影响；(3)确定ABA在植物对营养生长期和生殖生长期单因子和交互作用的响应中的重要性；(4)探讨ABA对共存因子下种子发育和休眠的调控。这些结果将为我们提供对植物对多种环境因素的反应的机械性理解，并有利于加拿大的农业。

Exploring plant responses to multiple co-occurring environmental factors is critical for a better understanding of how these factors affect plant production and seed development in the future. Although plants in nature are subject to multiple factors, most studies have considered only one factor at a time. The overall goal of this research program is to investigate the underlying mechanisms of plant responses to multiple environmental factors, associated with climate change. We hypothesize that plants respond differently to single and interacting environmental factors during vegetative and reproductive stages, and abscisic acid (ABA) is a key endogenous factor that serves as an important signaling molecule that enables the plant to generate protective responses to changing environments. We use three plant species from the family Brassicaceae: canola, stinkweed and Arabidopsis. Canola is a significant agricultural crop in Canada. Information on how it responds to the changing environment will be important to Canadian agriculture. Changes in the growth dynamics of weeds are also important to agriculture, as aggressive growth of weeds reduces yield of food crops. Stinkweed is selected for its wide distribution and local presence in Nova Scotia. Arabidopsis is selected because of its well-known responses to single stress factors and the large number of well-characterized mutants that vary in response to ABA. Mutant-based approach allows us to focus on specific questions at the biochemical, physiological or anatomical levels, and gain a mechanistic understanding of the process. The objectives of the proposed research are (1) to examine the single and interactive effects of CO2, temperature and watering regime on plant growth and development during vegetative and reproductive stages, (2) to elucidate the effects of these environmental factors on plant reproductive yield, (3) to determine the importance of ABA in plant responses to single and interactive factors during vegetative and reproductive stages, and (4) to explore ABA regulation of seed development and dormancy under co-occurring factors. The results should provide us with mechanistic understanding of plant responses to multiple environmental factors, and benefit Canada's agricultural industry.