Influence of tillage, mulching, weed control methods and butachlor application on certain soil properties, weeds and performance of upland rice [study conducted in the Philippines]
1982
Olofintoye, J.A.
A field experiment was conducted during the 1981 wet season at the UPLB, Central Experiment Station to evaluate the effects of zero and conventional tillage techniques, mulching and weed control methods on some soil properties, performance of an upland rice and weed growth. Another field experiment was designed to study the responses of two upland rice varieties to rate and time of application of butachlor under minimum tillage technique. This was preceeded by a pot experiment to test the tolerance of five upland rice varieties to rate of butachlor and it was followed by another pot experiment to study the responses of the two rice varieties to rate and time of application of butachlor under different moisture distributions. Effects of tillage techniques and mulching on soil moisture content, soil pH, available soil phosphorus, nitrate and ammonium forms of nitrogen and exchangeable calcium were significant. Source and level of organic matter decomposition appreciably affected rice crop establishment, growth and yield under zero tillage. Higher weed growth in zero tillage technique significantly reduced rice yield. The tolerance of five upland rice varieties to butachlor, within the rate of 0-3 kg a.i./ha was not significantly different. Injury to rice seedlings occurred when there was frequent irrigation water supply after application of butachlor, in amount sufficient to leach the herbicide into the zone where rice seeds were germinating
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