Effect of Fertilizer Application on Growth and Yield of Manihot esculenta Crantz.

To investigate the effect of chemical and organic fertilizer management on growth, yield and nutrient uptake of two cassava cultivars under rainfed conditions, the study was laid out in factorial in randomised complete block design with four replications. The six treatments were TR1) Kasetsart 50 with 312.50 kg ha-1 of 15-15-15, TR2) CMR 33-38-48 with 312.50 kg ha-1 of 15-15-15, TR3) Kasetsart 50 with 312.50 kg ha-1 of 15-7-18, TR4) CMR 33-38-48 with 312.50 kg ha-1 of 15-7-18, TR5) Kasetsart 50 with 6,250 kg ha-1 of organic fertilizer and TR6) CMR 33-38-48 with 6,250 kg ha-1 of organic fertilizer. The results illustrated that Kasetsart 50 responded to chemical fertilizer management especially, 312.50 kg ha-1 of 15-7-18 formula and 6,250 kg ha-1 of organic fertilizer at 1 and 4 months after planting respectively, better than CMR 33-38-48 in terms of storage root fresh and dry weights, percentage of total starch and amylose content. CMR 33-38-48 responds to chemical fertilizer management and organic fertilizers in terms of stem and leaf growth.