Nutrient status of mulberry soils of sericulturists under varied bivoltine sericultural clusters of Karnataka

The fertility of soil plays key role for the development of any farming crops and mulberry is no exception for it. Demand for essential nutrient supply to the soils ever growing due to intensive cropping systems. Therefore, additional supplementation of required organic and inorganic nutrients to retain the desired levels of soil nutrient status in mulberry is imperative for sustainable leaf production. In the present study a total of 1118 composite soil samples were collected from the traditional sericultural areas of 14 clusters under Cluster Promotion Programme (CPP) to assess the prevailing nutrient status spread over in 13 districts of Karnataka. The soils were subjected for the categorization of their soil types and chemical analysis to determine their soil reaction, salinity and nutrient status viz. pH, EC, OC, available macro (N, P & K) and micro (S, B, Zn, Fe, Mn & Cu) nutrients respectively. The perusal of the results indicated that out of the soils received, loamy soils recorded high (52%) followed by red (28%), black (12%) where as lateritic type in low (8%) among the soils categorised, indicating maximum soils are mulberry friendly. In regard to the soil reaction (pH) 59% soils recorded in desired level (6.5-75), 20% with low (<6.5) where as 21% soils in high pH (>7.5). Most of the cluster soils (97%) showed ideal range of soluble salts (<1.0 dS/m). Organic carbon (OC) was low in 80% soils (<0.65%) whereas 19% medium (0.65-1.0%) and only 1% soils recorded higher OC content (>1.0%). In case of macronutrients, available Nitrogen (N) recorded low in 70% soils (<250kg/ha) whereas Phosphorous (P) and Potassium (K) recorded high (>25kg/ha & >224kg/ha) in 44% and 62% soils, respectively. Micronutrients such as available S, B, Zn, Fe, Mn and Cu, sulphur (S: >15ppm) prevailed high in 71% soils, Boron (B) medium level (0.5-1.0 ppm) in 48%; 49% soils recorded low (<0.6ppm) in Zinc (Zn); Ferrous (Fe) was recorded high in (<4.5ppm) 67% soils; Manganese (Mn) high (>4.0) in 79% soils where as 86% soils recorded with high Copper content (Cu: >0.4%), respectively.