Mapping Current Micronutrients Deficiencies in Soils of Uttarakhand for Precise Micronutrient Management

Abstract

Content of micronutrients and their ability to supply to crop vary widely depending upon soil types, nature of crops grown, ecology and agro climatic variability. Total levels of micronutrient s are rarely indicative of plant availability, hence, rational management of micronutrient fertility and toxicity requires an understanding of how plant-available soil micronutrients vary across the soils. Soils deficient in their ability to supply micronutrients to crops are alarmingly widespread across the Uttarakhand State, and this problem is aggravated by the fact that many modern cultivars of major crops are highly sensitive to low micronutrient levels. Although micronutrient deficiencies (Zn-9.6, Mn-4.7, Fe-1.4, Cu-1.4, B-7.0 and Mo-0.9%) in Uttarakhand are much lower than the national average due to low pH, high organic carbon and favorable climate. However, frequency distribution of micronutrients into various category showed that large area in the state has potential to be deficient in future, which may respond to micronutrient applications. In order to understand the geographic distribution of available micronutrient content in soil of the state, soil micronutrient maps have been developed using GPS and GIS to improve our understanding regarding nature and extent of micronutrient deficiencies and their response to crop growth and development. The maps revealed that soils deficient in zinc, boron and manganese also exhibited crop response from 3.0 to 36%. However, deficiency of Fe, Cu and Mo is negligible. These maps and frequency distribution of available micronutrient content in soils will be highly useful in assessing fields’ scale variability for developing site-specific precision micronutrients management for better human and livestock health of Uttarakhand.