Increasing the resilience and sustainability of forage crops in a context of climate change

从全球来看，饲料作物是加拿大东部和魁北克省最重要的作物，仅魁北克省就种植了近100万公顷，其中苜蓿-草混合作物占主导地位。近年来，与气候变化相关的干旱和暖冬日益频繁，造成牧草短缺并危及持久性，影响了饲料作物的管理。因此，他们的种植面积不断减少，转而种植对环境影响更大的一年生粮食作物，尤其是玉米。饲料作物不仅是乳制品行业的核心，而且还有助于农业生产的可持续性，因为它们为环境提供了多种好处，如碳汇和减少侵蚀。本研究项目的长期目标是通过提高饲料作物和以饲料为基础的农业生态系统的生产力、营养价值和持久性，为在气候变化背景下提高其恢复力和可持续性的战略发展做出贡献。这将通过增加我们对影响饲料作物生长和发育的环境因素和管理决策的理解来实现。具体的短期目标是：1)在牧草短缺的情况下，确定最大限度地利用苏丹草作为建立多年生物种的伴生作物的条件；2)通过整合还原性木质素（RL）苜蓿品种，并研究这些混合物中植物的生长、发育和互补性，确定增加苜蓿-草混合物的饲料营养价值和持久性的潜力。在野外和受控环境中进行的实验中，我们将研究苏丹草（一种一年生牧草）的使用，这种牧草可用于增加多年生物种建立年的饲料产量，以解决与非生物胁迫相关的饲料短缺问题。这项研究的目的是增加我们对多年生物种在与苏丹草一起生长时将面临的竞争最小化的因素的理解。在田间试验中，我们还将研究新开发的还原性木质素苜蓿在加拿大东部的使用情况，那里的苜蓿主要与草混合种植。我们将研究还原性木质素紫花苜蓿在其发育过程中的木质素积累模式，以及混合生长时禾本科的木质素积累模式。这种理解将使我们能够确定最佳的苜蓿-草混合物，这将使生产者能够利用与草混合的还原性木质素苜蓿品种的优势。该计划将通过确保更稳定的易消化饲料供应来影响农业部门，这将满足经济和环境需求，因为更多地使用和持续使用更易消化的饲料与更有利可图的动物生产有关，对环境的影响也更小。

Forage crops are, taken globally, the most important crop in eastern Canada and Quebec in terms of area, being cultivated on almost one million hectares in Quebec alone among which alfalfa-grass mixtures predominate. Forage crop management has been affected in recent years by the increasing occurrence of drought and mild winters associated with climate change, which creates forage shortage and jeopardize persistence. Consequently, their acreage has been steadily reduced to the profit of annual grain crops, especially corn, which have a greater environmental impact. Forage crops are not only central to the dairy industry, but they also contribute to the sustainability of agricultural production as they provide multiple benefits to the environment acting as carbon sinks and reducing erosion. The long-term objective of this research program is to contribute to the development of strategies that will increase the resilience and sustainability of forage crops and forage-based agroecosystems in a context of climate change by increasing their productivity, nutritive value, and persistence. This will be achieved by increasing our understanding of environmental factors and management decisions affecting forage crops growth and development. Specific short-term objectives are to: i) identify conditions maximizing the success of Sudangrass use as a companion crop for the establishment of perennial species in a context of forage shortage, ii) determine the potential of increasing forage nutritive value and persistence of alfalfa-grass mixtures by integrating reduced-lignin (RL) alfalfa cultivars and studying the growth, development, and complementarity of plants included in these mixtures. In experiments conducted in the field and controlled environments we will research the use of Sudangrass, an annual forage, that can be used to increase forage production in the establishment year of perennial species to address forage deficits associated with abiotic stress. This research will aim at increasing our understanding of factors that will minimize competition faced by perennial species when grown with Sudangrass. In field experiments, we will also investigate the use of newly developed reduced-lignin alfalfa in the context of eastern Canada where alfalfa is predominantly grown in mixtures with grasses. We will study the lignin accumulation pattern of reduced-lignin alfalfa during its development along with that of grasses when grown in mixtures. This understanding will allow us to identify optimal alfalfa-grass mixtures that will allow producers to take advantages of reduced-lignin alfalfa cultivars in mixtures with grasses. This program will impact the agricultural sector by ensuring a more stable supply of more digestible forages, which will address both economic and environmental needs as a greater use and persistence of more digestible forages is associated with more profitable animal production with lower impact on the environment.