Rice Straw Management in the Area of Continuous Rice Planting

Abstract

Straw management by incorporation into the soils is an alternative method to avoid straw burning before land preparation. The experiment was conducted at Pathum Thani Rice Research Center and Suphan Buri Rice Research Center during 2006-2007. It was comprised of 3 trials, i.e., effect of amount of straw incorporated into soils to rice growth and yield, effect of straw management methods to rice growth and yield, and effect of straw incorporation period to rice growth and yield. The results showed that straw incorporation rate of 0-800 kg/rai did not affect early growth stage (number of plants/m² at 15 days after planting) and yield. Number of plants/m² at 15 days after planting was decreased by straw incorporation at the rate of 1,200-1,600 kg/rai whereas both the number of plants/m² at 15 days after planting and yield were decreased by straw incorporation at the rate of 2,000-2,400 kg/rai. The 3 methods of straw management, i.e., straw burning before land preparation, straw removing before land preparation, straw incorporation before land preparation, and minimum tillage did not affect rice growth and yield. Straw incorporation period of 0, 7, 14 and 21 days before planting in case of 800 kg/rai of straw did not affect yield of Suphanburi 1 but afffected the rice root growth. At the period of 0 and 7 days the roots appeared clumsy with brown and black color. Little young root was emerged. However, at the period of 14 and 21 days, the rice root was longer, bigger than those of 7 and 14 days. Root color was white. In the case of 1,200-1,800 kg/rai of straw incorporation, rice yield at the straw incorporation period of 0-14 days was lower than at the straw incorporation period of 21-28 days.