Work

Occurrence of oidium in cowpea influenced by cropping system and planting season

Year: 2026

Type: article

Abstract: Cowpea ( Vigna unguiculata (L.) Walp.) is a crop of major importance in semiarid regions, where powdery mildew can significantly reduce productivity. This study evaluated powdery mildew severity in four cowpea cultivars grown under monocropping and intercropping with two biomass sorghum ( Sorghum bicolor (L.) Moench) across two planting seasons (June and December 2021) under semiarid conditions. The experiment was conducted in a randomized complete block design arranged in a 12 × 2 factorial scheme with three replications, and disease severity was assessed at the R9 stage by means of the percentage of leaf area affected. Planting season significantly affected disease severity, and a significant season × treatment interaction was detected, indicating that the effects of cultivar and cropping system depended on planting season. Disease severity was higher in the June planting, whereas December planting reduced severity by 69.60%. Intercropping reduced disease severity for most cultivars during the June planting. Monocropping systems showed higher grain yield due to greater plant density, averaging 2.11 and 2.29 t ha − 1 in June and December planting, respectively, while intercropping averaged 1.15 and 1.22 t ha − 1 . However, intercropped cowpea maintained stable productivity per plant despite a 50% reduction in plant density. These results demonstrate that adjusting planting date and adopting intercropping with adapted cultivars can simultaneously reduce powdery mildew severity and maintain productive stability in semiarid cowpea systems.

Source: Agronomy Journal

DOI: 10.1002/agj2.70393

Authors: Layana Alves do Nascimento, Juliane Rafaele Alves Barros, Jadson Lima da Silva, Emília Hamada, Natoniel Franklin de Melo, Francislene Angelotti