Water stress in the maize x cowpea intercropping

Abstract

Maize (Zea rnays L.) cv. Jatinã C-3 and cowpea (Vigna unguiculata (L.) WaIp) cv. Pitiúba were grown in sole crop and in intercropping submitted to water stress at different growth stages. The experiment was carried out from November/1982 to March/1983 at Bebedouro Research Station, in Petrolina, PE, Brazil. The degree of water stress was based in relation to soil physic-hydraulic characteristcs. Plots were irrigated when soil moisture tension dedlined from about - 0.3 to - 0.4 MPa and - 0.02 to - 0.03 Mpa respectively for deficit and control treatments. Both soil water and plant water status were monitored. The effect of water stress in maize and cowpea plants was estimated by crop growth rate, seed yield and yield components. The maize yield was highly affected at the zeproductive phase. Moreover yield reduction was high in sole cropping. Under water stress, cowpea seed yield was not affected by water stress, but cropping systems had significant effect on seed yield due to the low number of pods per plant. The maize x cowpea intercropping was more efficient in terms of land equivalent ratio when water stress was present. Corn yield was more stable when intercropped with cowpea.