Effect of Fertilizer, Organic Manure and Bio-fertilizer on Summer Grown Cowpea (Vigna unguiculata L. Walp)

Abstract

In India, pulses are grown in an area of 25.21 million ha with a total production of 19.78 million tones with a productivity of 763 kg ha-1. In Gujarat, it is cultivated in an area of 6.54 lakh ha with an annual production of 5.99 lakh tonnes and average productivity of 916 kg ha-1(Anonymous 2016). About a dozen of pulse crops viz., chickpea, pigeonpea, green gram, black gram, lentil, field pea, lathyrus, cowpea, common bean, moth bean, horse gram and rice bean are cultivated under varied agro-ecological conditions. Among the pulses, cowpea serves as a dual purpose food at both green shell and dry stage but its productivity is low owing to different reasons. In general pulses respond well to phosphorous application and seed inoculation with Rhizobium (Prasad and Sanoria 1984) but response could be larger if organic manure is supplemented. As such information for enhancing the productivity of cowpea is limited and hence the present investigation was carried out. A field experiment was conducted at B.A College of Agriculture, Anand Agricultural University, Anand during summer 2018 with cowpea (var. GC4) as test crop. The experimental soil was loamy sand with low organic carbon and available nitrogen (124.85 kg ha-1), medium available P2O5 (29.23 kg ha-1) and high available K2O (286.76 kg ha-1). There were 12 treatment namely, T1-no fertilizer (control); T2-RDF 20-40-00 kg ha-1 (NPK); T3-castor cake @ 0.5 t ha-1; T4-vermicompost @ 1 t ha-1; T5-FYM @ 4 t ha-1; T6-castor cake @ 0.5 t ha-1 + PSB @ 5 ml kg-1 seed; T7-vermicompost @ 1 t ha-1 + PSB @ 5 ml kg-1 seed; T8-FYM @ 4 t ha-1 + PSB @ 5 ml kg-1 seed; T9-Rhizobium @ 5 ml kg-1 seed + PSB @ 5 ml kg-1 seed; T10- castor cake @ 0.25 t ha-1 + Rhizobium @ 5 ml kg-1 seed + PSB @ 5 ml kg-1 seed; T11-vermicompost @ 0.5 t ha-1 + Rhizobium @ 5 ml kg-1 seed + PSB @ 5 ml kg-1 seed and T12- FYM @ 2 t ha-1 + Rhizobium @ 5 ml kg-1 seed + PSB @ 5 ml kg-1 seed in a Randomized Block Design with four replications. Chemical fertilizers were applied through urea and DAP but organic manures viz. castor cake and FYM were applied well in advance for proper decomposition whereas vermicompost was applied on the day of sowing. As per the seed rate (25 kg ha-1), the required seed/plot (3.60 m x 5.0 m) were inoculated with respective strains of Rhizobium (broth) and PSB (broth) and sown on 21st February. Crop was harvested in second week of May. The cowpea raised under recommended agro-practices and the data generated during experiment was statistically analyzed (Panse and Sukhatme 1967).