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Abstract

In 1983, a trial was carried out at the Alanje Experiment Station of the Panamanian Agricultural Research Institute to determine what changes occur in the physico-chemical characteristics of the soil as a result of soil tillage and what effects this may have on yields of upland rice. Two tillage practices, conventional and minimum, were compared under three different insect controls: no control, soil pest control and foliar pest control. Soil penetrability and available water were determined at two depths during the most important crop growth phases, and samples were taken to determine nutrient availability, water content and bulk density. With the sole exception of soil penetrability which was greater under conventional tillage none of the valiables measured were significantly changed by tillage method. Insect control type and date and depth of sampling produced significant differences in these variables. However, the similar behavior of the soil under both tillage methods resulted in there being no significant defferences in yields.