D B Pagnoncelli Fortunato, Trezzi Michelangelo M, Gonzalez-Andujar Jose L
Department of Agronomy, Federal University of Technology-Paraná, Pato Branco 85503-390, Brazil.
Department of Crop Protection, Institute for Sustainable Agriculture (CSIC), Spain and International Laboratory on Global Change (LINCGlobal) (CSIC), 14005 Córdoba, Spain.
Plants (Basel). 2020 Mar 4;9(3):325. doi: 10.3390/plants9030325.
Italian ryegrass () is an annual grass widely distributed in cultivated crops around the world. This weed causes significant yield reduction in many crops and has developed herbicide resistance. The aim of this study was to develop a cohort-based stochastic population dynamics model that integrates both emergence (thermal time) and dynamic population models as a tool to simulate the population dynamics of susceptible and resistant populations of under the effects of climate change. The current climate scenario and the increase in the average air temperature by 2.5 °C were considered. Chemical and cultural management strategies commonly used in the South Region of Brazil during the winter and summer seasons were incorporated into the model. In the absence of control and under the current climate conditions, the seed bank population grew until reaching an equilibrium density of 19,121 ± 371 seeds m for the susceptible and 20463 ± 363 seeds m for the resistant populations. Considering the second climate scenario, the seed bank reaches an equilibrium density of 24,182 ± 253 seeds m (+26% in relation to the current scenario) for the susceptible population and 24,299 ± 254 seeds m (+18% in relation to the current scenario) for the resistant one. The results showed that the effect of the rise in temperature implies an increase in population in all the management strategies in relation to the current climate scenario. In both climate scenarios, the strategies based on herbicides application controlling cohorts 1 and 2 were the most efficient, and cropping systems including winter oat-soybeans rotation had a smaller impact on the seed bank than crop rotations including winter wheat or summer corn. Crop rotations including wheat and corn for management as an adaptive strategy under the future climate change are suggested.
意大利黑麦草（Lolium multiflorum）是一种一年生草本植物，广泛分布于世界各地的栽培作物中。这种杂草会导致许多作物大幅减产，并且已经产生了除草剂抗性。本研究的目的是开发一种基于队列的随机种群动态模型，该模型整合了出苗（热时间）和动态种群模型，作为模拟气候变化影响下意大利黑麦草敏感种群和抗性种群动态的工具。考虑了当前的气候情景以及平均气温升高2.5摄氏度的情况。巴西南部地区冬夏两季常用的化学和栽培管理策略被纳入该模型。在没有防治措施且在当前气候条件下，易感种群的种子库数量增长直至达到平衡密度19,121 ± 371粒/平方米，抗性种群的平衡密度为20,463 ± 363粒/平方米。考虑第二种气候情景，易感种群的种子库达到平衡密度24,182 ± 253粒/平方米（相对于当前情景增加26%），抗性种群的平衡密度为24,299 ± 254粒/平方米（相对于当前情景增加18%）。结果表明，温度升高的影响意味着与当前气候情景相比，所有管理策略下的种群数量都会增加。在两种气候情景下，基于除草剂应用控制第1和第2队列的策略最为有效，包括冬燕麦 - 大豆轮作的种植系统对意大利黑麦草种子库的影响小于包括冬小麦或夏玉米的作物轮作。建议采用包括小麦和玉米轮作来管理意大利黑麦草的种植系统，作为未来气候变化下的一种适应性策略。
