Abstract
Field experiments were carried out to evaluate relative efficacy of organic manures in improving productivity and pest tolerance of an okra (Abelmoschus esculentus L.) crop in Lateritic sandy-loam soil. Three commercial manures, viz., processed city waste (PCW), vermicompost (VC), and oil cake pellets (OCP), were assessed in relation to farmyard manure (FYM) alone and in combination with microbial culture (FYM + MC). All were compared to chemical fertilizer (CF). Among the organic manures tested, FYM produced maximum fruit and shoot yield. The uptake of N, P, and K and micronutrients in FYM treatment were significantly superior to all other commercial manuring and CF. Increase in fruit yield with FYM application was attributed to higher retentivity of soils for water and nutrients and higher uptake of major and minor nutrients. However, the tolerance of these crop plants to attack by pathogens and pests in terms of fruit yield was highest in the treatment with FYM. The quantity and the proportion of N, P, and K coupled with minor elements available from nutrient sources were mainly responsible for differences among nutrient sources.
