Suitability of different soil test methods for available P and its critical limits in green gram (Vigna Radiata) under temperate conditions

A pot culture experiment was conducted with green gram on the soil of two agro climatic zones of Kashmir during kharif 2005 and 2006 at Shalimar campus for selecting the most suitable chemical extractant for available phosphorus and determining critical limit of available P in these soils. Among different indices of P availability, Olsen's and Hunter's methods were found to be significantly and positively correlated with yield and P uptake of green gram. Critical concentration of phosphorus was 14.40 and 14.80 ppm P₂O₅ for Olsen's and Hunter's method, respectively. The critical concentration in grain and straw of green gram were 0.34 and 0.13 per cent, respectively.