Available Copper, Boron and Iron Status of Rajasthan soils

Available micronutrient elements (Cu, B & Fe) were determined in representative soils of seven soil groups, covering fifteen districts of Rajasthan. Available copper, boron and iron content in these soils ranged from 0 05 ppm to 5.6 ppm, 0.02 ppm to 2.0 ppm and 0.3 ppm to 15.7 ppm respectively. On an average, maximum available copper was found in undifferentiated alluvium soils and minimum in desert soils. Available boron and iron were found maximum in desert and mixed red and black soils respectively, while grey brown soils contained minimum amount of both the elements among all the soil groups. Most of these soils seem to possess adequate quantity of these elements for normal crop growth. No consistent relationship in different soil groups was observed between available contents of these elements and pH as well as calcium carbonate content of soils. With increase in organic matter content of soils, available nutrients increased although such increases were significant in some of the soil groups only.