Effect of Paclobutrazol on KDML 105 Rice Quality and Its Residue

Abstract

A field experiment was conducted as Srisamrong Rice Experiment Station on a sandy clay loam to examine the response of KDML 105 rice with the appliction of paclobutrazol and fertilizer. The effects of paclobutrazol and fertilizer on rice were determined in terms of qulity and paclobutrazol residue in the rice grain. A randomiszed complete block design with two factors factorial (fertilizer x plant growth regulator) with 4 replications was used. Fertilizer; at the rate of 18-6-6 band 24-6-6 kg N2O5-K2O/rai were combined with 0, 25, 50 and 75 g ai paclobutraxol/rai including one check without fertilizer and paclobutrazol. Results showed that protein and amylose content were not significantly different among rice receiving paclobutrazsol but their content varied with applied fertilizer. With no fertilizer, the average protein content was 6.87 percent and increased to 8.50 and 9.34 percent as nitrogen rate increased. Amylose content of no applied fertilizer was 23.11 percent but decreased to 22.35 and 22.13 with an increase of nitrogen rate. Residual pclobutraszol was not detected in rice grain.