Effect of Soil Texture and Precipitation on Phosphorus Leaching in Alfisols of Meghalaya

Lysimeter study was conducted in 1987 and 1988 on three soils of Meghalaya, varying in texture, to quantify the leaching loss of P due to precipitation. There was no leaching of P from two soils having 23.8 and 18.4% claycontent. However, P was found to leach from the soil having 8.4% of clay. Maximwn leaching of Pfrom this soil was 3.84 kg ha⁻¹ in 1987 and 4.20 kg ha⁻¹ in 1988. Leaching of P was found to be associated, besides clay content and composition of the soil, with the amount of rainfall received and the applied phosphorus. Leaching of P increased from 0.88 to 3.84 kg ha⁻¹ in 1987 and 0.98 to 420 kg ha⁻¹ in 1988 without P and with the application of P @ 60kgP ha⁻¹ along with 10 t ha⁻¹ FYM, respectively. Loss of P was higher by 10.9% in 1987 and 9.3% in 1988 when FYM (10 t ha⁻¹) was applied along with P (60 kg ha⁻¹) as against P applied alone. Dry matter yield of potato and P uptake increased significantly with applied P. Application of FYM along with P increased the dry matter yield by 13.0% and P uptake by 14.0% over P applied alone.