Preliminary Trials for the Response of Guatemala Corn to Sulfur and Trace Elements in Red Brown Earth Soil of Thailand1

บทคัดย่อ

Thailand is located in the general area where soil are highly weathered, for the region is tropical and relatively humid. Soils are quite low in many essential nutrient elements. The newly opened land, when cultivated for some years, tends to become depleted in fertility rather rapidly. Nitrogen, phosphorus and potassium have been reported elsewhere to be the first elements to become limiting in crop production on most soil. Consequently the majority of research concerning the crop production improvement in Thailand is concentrated primarily on the problems of raising the levels of nitrogen, phosphorus and potassium.