Analysis of Different Management Strategies for Annual Ryegrass (Lolium rigidum) Based on a Population Dynamic Model

Abstract

Weed species present high competitive capacity, rapid adaptability and herbicide resistance, hindering their effective control across worldwide cropping regions. Since field-conducted experiments are very time-consuming and usually expensive, mathematical population-based models are valuable tools to test and develop long-term weed management programs. Within this context, the objective of this paper is to formalize analytically the possible seed bank dynamics of the Lolium rigidum, subjected to different control strategies. The first focus is on studying in detail the effects of integrating constant actions, promoting more environmentally and economically sustainable scenarios. From the same perspective, an alternative to applying time-variant programs is introduced. The proposed control guarantees that the weed population is sufficiently small or, alternatively, is kept below a given economic threshold level in a ten-year planning horizon. Furthermore, an optimization criterion is adopted for distributing necessary efficiency into diverse integrated options. Numerical simulations are included to illustrate the analytical findings.

Effect of Barley Sowing Density on the Integrated Weed Management of Lolium rigidum (Annual Ryegrass) in Mediterranean Dryland: A Modeling Approach

“…which permits us to determine if the IWM programs can achieve (or not) weed extinction in the long-term horizon [15]. In particular, if a specific program results in an equivalent efficiency value such that c ≥ c 0 , then the adult L. rigidum population goes to the extinction.…”

“…Mathematical models providing information about L. rigidum dynamics demonstrated to be useful for predicting field emergence and spatial distribution as well as for testing different management strategies [13][14][15][16][17][18]. In particular, the population model proposed by González-Andújar and Fernández-Quintanilla [13] permits us to predict the actual population density based on its value in the previous year and the progress of the species during its different life-cycle stages.…”

“…In particular, the population model proposed by González-Andújar and Fernández-Quintanilla [13] permits us to predict the actual population density based on its value in the previous year and the progress of the species during its different life-cycle stages. Based on this model, the performance of different control strategies for L. rigidum was formalized by D'Amico et al [15]. Analytical results related to the long-term behavior of the species showed that the population could not reach extinction by applying an individual control action in the field.…”