Crop rotations involving corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] are well‐known production systems across the Midwestern United States, but the addition of wheat (Triticum aestivum L.) in the rotation has received less attention. Additionally, the interactive effect of crop rotation with nitrogen (N) fertilizer and foliar fungicide application on yields for these three crops is not yet well understood. Data were collected in Wisconsin from a long‐term crop rotation experiment during 2013 to 2015 to measure corn (grain and silage), soybean, and wheat yield response to crop rotation frequency (seven rotations involving corn, soybean, and wheat), six levels of N, and foliar fungicide use. During the 3 yr of the experiment, minimal interactive effects were detected, which suggested that the examined management decisions can remain separate for growers in Wisconsin. Yearly crop rotation of corn and soybean increased corn grain yields in 2014 by 15 to 18% and soybean yields by 24 to 31% in 2015 compared with continuous cropping. No other crop rotation effect was observed. Fungicide use at the V5 growth stage for corn, at R3 for soybean, and at GS9 for wheat, increased wheat (7.4–16.8%) and soybean yield (3.6–5.4%) but not corn grain or silage yields. Nitrogen application was more beneficial for corn compared with wheat and soybean. The effect of N on soybean was similar across all rotations, and grain yields increased when N rate was higher than 100 kg ha−1. The data suggest that N rate recommendations should be based on crop needs, regardless the rotation system.

Corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotations are common production systems across the midwestern United States. However, the interactive effect of crop rotation, tillage, and nematicide seed treatments on the yield of both crops in the rotation system is not well understood. Field trials were conducted in a long‐term crop rotation experiment during 2013 to 2015 to measure yield response of both corn and soybean to three factors: (i) tillage system (no‐till [NT] and conventional), (ii) crop rotation frequency (14 sequences involving corn and soybean), and (iii) three nematicide seed treatments (a control, abamectin/Pasteuria nishizawae, and Bacillus firmus). Rotations that involved consecutive years of soybean exhibited the greatest nematode populations in the soil, whereas, consecutive years of corn resulted in lower nematode populations. No significant differences in nematode populations were observed among the other examined management practices. Conventional tillage resulted in up to 18% greater corn and 10% greater soybean yield than NT. Yearly crop rotation increased corn yield by 20% and soybean yield by 22% compared with continuous cropping. Seed treatment nematicides had no effect on corn and soybean yield. The production system that involved yearly rotation of corn and soybean, regardless of tillage system and nematicide seed treatment, exhibited the greatest yield potential during the 3 yr of this study. Such rotation system using NT can be an attractive option for farmers in this region, since NT has reduced field operations and labor requirements.

--Introduction. Cropping systems of the mango trees in West Africa are very varied. Each one of them developed in a specific context where the agronomical practices and the varietal composition of the orchards contribute to the diversity observed. The study undertaken should make it possible to understand better the influence of the potential outlets on the evolution of the regional mango production. Principal cropping systems. In the studied area, most of the mango orchards are smaller than 10 ha; their production is extensive and uses few inputs. They belong mainly to growers whose principal activity is centred on agriculture. Certain plantations of nearly 100 ha, found in Senegal or in Côte d'Ivoire, belong to exporters and profit from technical assistance. Agronomical practices. Study of the agronomical practices used in mango orchards of West Africa made it possible to analyze the aspects of seedling production, choice of the site, installation of the orchard before plantation, plantation and maintenance of the trees, fire protection and water management, as well as the effect of the export market on the varietal choice and the varietal offer during a harvest campaign. Diseases and enemies. An inventory of the pathological problems and physiological diseases likely to devalue production were carried out. Marketing. This part made it possible to distinguish intercontinental exports, requiring a specific harvest and conditioning organization, and the local, national and regional markets. Processing. Today, the share of processed mangos in West Africa uses only a negligible proportion of the total production. Conclusion and prospects. Beside traditional production, which presents signs of brittleness, appear modern orchards. More than a necessary intensification of the orchards, a rationalization of the agronomical practices, plant health protection, fruit harvest and handling are impossible to circumvent. Further, the export path is confronted with a fast evolution of the exogenous regulations, based on increasingly strict qualitative and sanitary standards.Francophone Africa / Mangifera indica / cropping systems / cultivation / plant diseases / marketing La mangue en Afrique de l'Ouest francophone : les systèmes de production et les itinéraires techniques.Résumé --Introduction. Les systèmes de production du manguier en Afrique de l'Ouest sont très variés. Chacun d'eux s'est développé dans un contexte spécifique où l'itinéraire technique et la composition variétale des plantations contribuent à la diversité observée. L'étude entreprise devrait permettre de mieux comprendre l'influence des débouchés potentiels sur l'évolution de cette filière horticole. Les principaux systèmes de plantation. Dans la région étudiée, l'essentiel des vergers de manguiers exploités a moins de 10 ha ; leur production est extensive et utilise peu d'intrants. Ils appartiennent en majorité à des planteurs dont l'activité principale est centrée sur l'agriculture. Certaines plantations proches de 100 ha, trouvées au Sénégal ou ...

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--Introduction. Cropping systems of the mango trees in West Africa are very varied. Each one of them developed in a specific context where the agronomical practices and the varietal composition of the orchards contribute to the diversity observed. The study undertaken should make it possible to better understand the influence of the potential outlets on the evolution of the regional mango production. Principal cropping systems. In the studied area, the main part of the mango orchards has less than 10 ha; their production is extensive and uses few inputs. They belong in majority to growers whose principal activity is centred on agriculture. Certain plantations close to 100 ha, found in Senegal or in Côte.d'ivoire, belong to exporters and profit from a technical assistance. Agronomical practices. The study of the agronomical practices used in mango orchards of West Africa made it possible to analyze the aspects of seedling production, choice of the site, installation of the orchard before plantation, plantation and maintenance of the trees, fire protection, water management, as well as the effect of the export market on the varietal choice and the varietal offer during a harvest campaign. Diseases and enemies. An inventory of the pathological problems and physiological diseases likely to devalue the production were carried out. Marketing. This part made it possible to distinguish intercontinental exports, requiring a specific harvest and conditioning organization, and the local, national and regional markets. Processing. Today, the share of transformed mangos into West Africa uses only one negligible proportion of the total production. Conclusion and prospects. Beside a traditional production which presents signs of brittleness appear modern orchards. More than a necessary intensification of the orchards, a rationalization of the agronomical practices, plant health protection, fruit harvest or handling are impossible to circumvent. Downstream, the export path is confronted with a fast evolution of the exogenous regulations, based on qualitative and sanitary standards increasingly strict.Francophone Africa / Mangifera indica / cropping systems / cultivation / plant diseases / marketing La mangue en Afrique de l'Ouest francophone : les systèmes de production et les itinéraires techniques.Résumé --Introduction. Les systèmes de production du manguier en Afrique de l'Ouest sont très variés. Chacun d'eux s'est développé dans un contexte spécifique où l'itinéraire technique et la composition variétale des plantations contribuent à la diversité observée. L'étude entreprise devrait permettre de mieux comprendre l'influence des débouchés potentiels sur l'évolution de cette filière horticole. Les principaux systèmes de plantation. Dans la région étudiée, l'essentiel des vergers de manguiers exploités a moins de 10 ha ; leur production est extensive et utilise peu d'intrants. Ils appartiennent en majorité à des planteurs dont l'activité principale est centrée sur l'agriculture. Certaines plantations proches de 100 ha...