MICRONUTRIENT AVAILABILITY ASSESSMENT OF TOMATO GROWN IN TALUKA BADIN, SINDH

Abstract

This study was conducted to assess the micronutrient status of soils and associated plant tissues in major tomato growing areas of Taluka Badin, Sindh. Composite soil and plant (3rd leaf from top) samples were collected from 32 major growing areas of Taluka Badin and analyzed for copper (Cu), iron (Fe), manganese (Mn), zinc (Zn) and boron (B) along with selected physico-chemical properties of soils. Majority of the soils were clayey in texture (81%), non-saline (80%), alkaline and poor in organic matter. All soils were adequate in AB-DTPA extractable Cu (>0.5 mg kg-1), Fe (>4 mg kg-1), and Mn (>1.8 mg kg-1) contents. Whereas AB-DTPA extractable soil Zn and hot-water soluble B values varied in a different way. Sixty six percent soils were low (<1.0 mg kg-1), 28% marginal (1.0-1.5 mg kg-1), and only 6% were adequate (>1.5 mg kg-1) in soil Zn. Ninety one percent samples were low (<0.5 mg kg-1) and only 9% were adequate (>1.0 mg kg-1) with regard to B. The data regarding plant analysis depicted that all samples were high in Fe (> 200 mg kg-1), whereas Cu was high (> 20 mg kg-1) in 19% samples and sufficient (5-20 mg kg-1) in 81% samples. Manganese was sufficient (40-250 mg kg-1) in 94% samples and low (30-39 mg kg-1) in 6% samples. Plant Zn analysis showed that 53% samples were high (>50), 22% samples sufficient (20-50 mg kg-1) and 25% low (18-19 mg kg-1) in Zn supply. Plant analysis of B showed that 59% samples were low (20-24 mg kg-1) and 41% were sufficient (25-60 mg kg-1). The relationship between soil and plant nutrient status was highly significant with “R2 ” value ranging from 0.57–0.81. It is concluded that micronutrients fertilization along with organic manures may be included in fertilization program. Further research may be conducted on wide range sampling strategy of study area.