Cowpea Adaptability to Southeastern Organic Farming Systems: Forage Productivity and Charcoal Rot Susceptibility

Cowpea (Vigna unguiculata (L.) Walp.) is a warm-season, multi-purpose legume that is well-adapted to the southeastern USA and has many traits that make it an attractive forage or cover crop for integration into organic production systems, including high rates of nitrogen (N) fixation, phosphorus (P) use efficiency, regrowth ability, and high digestibility. Eight cowpea varieties were evaluated under organic management at two locations in summer 2014 for stand establishment, forage yield and quality, and weed biomass.

Charcoal rot [Macrophomina phaseolina (Tassi) Goid.] is a fungal disease that is economically important to many host plant species. High temperatures and drought conditions favor disease development making it difficult to predict when disease outbreak will occur. Cowpea (Vigna unguiculata L. Walp.) is an important crop for many regions of the globe and is a host species for M. phaseolina. Efforts have been made to breed genetic lines that are resistant to M. phaseolina but little research has been done to screen many popular cowpea cultivars for resistance. This study includes an inoculated field trial and greenhouse seedling screening of twenty-six cowpea lines to identify resistance to charcoal rot.