Direct and residual effects of lime on soil characteristics, yield and nutrient uptake of maize (Zea mays) and soybean (Glycine max) in an acid hill soil of Manipur

Abstract

A field experiment was conductcd during the rainy season of 1994 and 1995 on maize (Zea mays L.) succeeded by soybean [Glycine max (L.) Merr.] during 1996 and 1997, to study the direct and residual effects of lime in an acid hill Ultisol of Manipur. Liming increascd the base saturation and reduced the exchangeable aluminium content to nil. All the forms of potassium, viz water-soluble, exchangeable, non-exchangeable and step K, declined with increasing doses of lime (0.25, 0.50 and 0.75 lime requirement levels). The maize yielded maximum (2.83 and 2.70 tonnes/ha during 1994 and 1995 respectively) with 0.25 lime requirement level, beyond which its yield decreased significantly to 1.70 and 1.80 tonnes/ha during 1994 and 1995 respectively with 0.75 lime requirement level. The residual effcct of lime @ 0.50 lime requirement increased the yield of soybean to 1.00 and 0.99 tonnes/ha (maximum) during third and fourth year of the lime applied. The potassium concentration of both the crops decreased with increasing lime levels. The nutrient uptake, viz N, P and K, by grains of both the crops showed similar trend as that of their respective grain yield.