The Influence of High-Quality Organic Fertilizer and Chemical Fertilizer on Growth Yield and Starch Content of Cassava cv. Kasetsart 50

Abstract

This research aim to study the effect of using high quality organic fertilizer and chemical fertilizer on growth, yield and starch content of cassava cv. Kasetsart 50. The experiment was conducted under field conditions at Ban Donhun, Thasongkorn sub-district, Muang district, Maha Sarakham province during May 2014 to February 2015. The field experiment was laid out in a Randomized Complete Block Design (RCBD) with four replications. The four treatments consisted of 1) no application of fertilizer (T1), chemical fertilizer formula 15-15-15 at the rate of 50 kg/rai (1 rai = 0.16 ha) combined with fertilizer formula 15-7-18 at the rate of 50 kg/rai, 3) high quality organic fertilizer at the rate of 400 kg/rai (T3) and 4) high quality organic fertilizer at the rate of 200 kg/rai combined with chemical fertilizer formula 15-15-15 at the rate of 25 kg/rai + fertilizer formula 15-7-18 at the rate of 25 kg/rai (T4).The results found that the application of chemical fertilizer formula 15-15-15 at the rate of 50 kg/rai + 15-7-18 at the rate of 50 kg./rai was the highest growth and starch content of cassava roots (75.20 % by dry weight). However, the yield (roots fresh weight) of this treatment was not significant different from the other treatments. Casava applied with high quality
organic fertilizer at the rate of 200 kg/rai combined with chemical fertilizer formula 15-15-15 at the rate of 25 kg/rai and fertilizer formula 15-7-18 at the rate of 25 kg/rai tended to have a higher roots fresh weight (4,309.4kg/rai) followed by cassava applied with chemical fertilizer formula 15-15-15 at the rate of 50 kg/rai + fertilizer formula 15-7-18 at the rate of 50 kg/rai (4,016.0 kg./rai) and high quality organic fertilizer at the rate of 400 kg/rai (3,776.1kg/rai), respectively. Whereas, cassava was treated
without fertilizer had low tuber yield (3,018.7kg/rai) and low starch content.