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The design of crop-pest management systems in the context of integrated fruit production (IFP) is a complex decision-making process for which model-based design approaches are of growing interest. In this study, such an approach was developed to enhance the management of the Prunus persica (L.) Batsch-Myzus persicae (Sulzer) (Homoptera: Aphididiae) system. Firstly, we developed a process-based model and defined a set of performance criteria in line with IFP objectives. The model describes the interacting peach-aphid dynamics, fruit production and fruit quality, and their control by (i) cultural practices, (ii) releases of the biological control agent Harmonia axyridis Pallas (Coleptera: Coccinellidae) and (iii) insecticide applications. Secondly, model simulations of pre-defined management scenarios were performed. Scenarios were based on theoretical pest control strategies (i.e., 'no treatment', 'conventional', 'organic farming' and 'integrated') and combined different levels of cultural and pest control management variables. The relationships between management and performance variables were studied. Thirdly, the simulation model was coupled with a multi-objective optimization module to design new management scenarios for three virtual farmer production profiles that varied in terms of the relative importance the farmer attaches to each one of the performance criterion. Our results showed that agronomic performances were largely explained by cultural practices, while aphid pressure was largely explained by pest control strategies. Under the 'no-treatment' strategy, aphid pressure displayed a bell-shaped response to nitrogen levels and increased with pruning intensity. These responses were attenuated or even reversed under the other strategies. The scenarios using the 'conventional' (insecticide-based) pest control strategy were the best, regardless of the farmer profile. However, scenarios using the 'no-treatment' strategy had good performances as well, as long as

The design of crop-pest management systems in the context of integrated fruit production (IFP) is a complex decision-making process for which model-based design approaches are of growing interest. In this study, such an approach was developed to enhance the management of the Prunus persica (L.) Batsch-Myzus persicae (Sulzer) (Homoptera: Aphididiae) system. Firstly, we developed a process-based model and defined a set of performance criteria in line with IFP objectives. The model describes the interacting peach-aphid dynamics, fruit production and fruit quality, and their control by (i) cultural practices, (ii) releases of the biological control agent Harmonia axyridis Pallas (Coleptera: Coccinellidae) and (iii) insecticide applications. Secondly, model simulations of pre-defined management scenarios were performed. Scenarios were based on theoretical pest control strategies (i.e., 'no treatment', 'conventional', 'organic farming' and 'integrated') and combined different levels of cultural and pest control management variables. The relationships between management and performance variables were studied. Thirdly, the simulation model was coupled with a multi-objective optimization module to design new management scenarios for three virtual farmer production profiles that varied in terms of the relative importance the farmer attaches to each one of the performance criterion. Our results showed that agronomic performances were largely explained by cultural practices, while aphid pressure was largely explained by pest control strategies. Under the 'no-treatment' strategy, aphid pressure displayed a bell-shaped response to nitrogen levels and increased with pruning intensity. These responses were attenuated or even reversed under the other strategies. The scenarios using the 'conventional' (insecticide-based) pest control strategy were the best, regardless of the farmer profile. However, scenarios using the 'no-treatment' strategy had good performances as well, as long as

The design of crop-pest management systems in the context of integrated fruit production (IFP) is a complex decision-making process for which model-based design approaches are of growing interest. In this study, such an approach was developed to enhance the management of the Prunus persica (L.) Batsch-Myzus persicae (Sulzer) (Homoptera: Aphididiae) system. Firstly, we developed a process-based model and defined a set of performance criteria in line with IFP objectives. The model describes the interacting peach-aphid dynamics, fruit production and fruit quality, and their control by (i) cultural practices, (ii) releases of the biological control agent Harmonia axyridis Pallas (Coleptera: Coccinellidae) and (iii) insecticide applications. Secondly, model simulations of pre-defined management scenarios were performed. Scenarios were based on theoretical pest control strategies (i.e., 'no treatment', 'conventional', 'organic farming' and 'integrated') and combined different levels of cultural and pest control management variables. The relationships between management and performance variables were studied. Thirdly, the simulation model was coupled with a multi-objective optimization module to design new management scenarios for three virtual farmer production profiles that varied in terms of the relative importance the farmer attaches to each one of the performance criterion. Our results showed that agronomic performances were largely explained by cultural practices, while aphid pressure was largely explained by pest control strategies. Under the 'no-treatment' strategy, aphid pressure displayed a bell-shaped response to nitrogen levels and increased with pruning intensity. These responses were attenuated or even reversed under the other strategies. The scenarios using the 'conventional' (insecticide-based) pest control strategy were the best, regardless of the farmer profile. However, scenarios using the 'no-treatment' strategy had good performances as well, as long as

The design of crop-pest management systems in the context of integrated fruit production (IFP) is a complex decision-making process for which model-based design approaches are of growing interest. In this study, such an approach was developed to enhance the management of the Prunus persica (L.) Batsch-Myzus persicae (Sulzer) (Homoptera: Aphididiae) system. Firstly, we developed a process-based model and defined a set of performance criteria in line with IFP objectives. The model describes the interacting peach-aphid dynamics, fruit production and fruit quality, and their control by (i) cultural practices, (ii) releases of the biological control agent Harmonia axyridis Pallas (Coleptera: Coccinellidae) and (iii) insecticide applications. Secondly, model simulations of pre-defined management scenarios were performed. Scenarios were based on theoretical pest control strategies (i.e., 'no treatment', 'conventional', 'organic farming' and 'integrated') and combined different levels of cultural and pest control management variables. The relationships between management and performance variables were studied. Thirdly, the simulation model was coupled with a multi-objective optimization module to design new management scenarios for three virtual farmer production profiles that varied in terms of the relative importance the farmer attaches to each one of the performance criterion. Our results showed that agronomic performances were largely explained by cultural practices, while aphid pressure was largely explained by pest control strategies. Under the 'no-treatment' strategy, aphid pressure displayed a bell-shaped response to nitrogen levels and increased with pruning intensity. These responses were attenuated or even reversed under the other strategies. The scenarios using the 'conventional' (insecticide-based) pest control strategy were the best, regardless of the farmer profile. However, scenarios using the 'no-treatment' strategy had good performances as well, as long as

The analysis of animal movement within different landscapes may increase our understanding of how landscape features affect the perceptual range of animals. Perceptual range is linked to movement probability of an animal via a dispersal kernel, the latter being generally considered as spatially invariant but could be spatially affected. We hypothesize that spatial plasticity of an animal's dispersal kernel could greatly modify its distribution in time and space. After radio tracking the movements of walking insects (Cosmopolites sordidus) in banana plantations, we considered the movements of individuals as states of a Markov chain whose transition probabilities depended on the habitat characteristics of current and target locations. Combining a likelihood procedure and pattern-oriented modelling, we tested the hypothesis that dispersal kernel depended on habitat features. Our results were consistent with the concept that animal dispersal kernel depends on habitat features. Recognizing the plasticity of animal movement probabilities will provide insight into landscape-level ecological processes.

The analysis of animal movement within different landscapes may increase our understanding of how landscape features affect the perceptual range of animals. Perceptual range is linked to movement probability of an animal via a dispersal kernel, the latter being generally considered as spatially invariant but could be spatially affected. We hypothesize that spatial plasticity of an animal's dispersal kernel could greatly modify its distribution in time and space. After radio tracking the movements of walking insects (Cosmopolites sordidus) in banana plantations, we considered the movements of individuals as states of a Markov chain whose transition probabilities depended on the habitat characteristics of current and target locations. Combining a likelihood procedure and pattern-oriented modelling, we tested the hypothesis that dispersal kernel depended on habitat features. Our results were consistent with the concept that animal dispersal kernel depends on habitat features. Recognizing the plasticity of animal movement probabilities will provide insight into landscape-level ecological processes.