Long-term Forage Yields of Five Tropical Grasses on an Extremely Sodic Soil and the Resultant Soil Amelioration

Abstract

SUMMARYA long-term field study was conducted from 1979 to 1985 in the Karnal district of Haryana, India to evaluate the effect of three rates of gypsum (0, 5.2 and 10.4 kg ha−1) on the performance of five grasses (Diplachne fusca, Panicum laevifolium, P. antidotale, Chloris gayana and Cynodon maritimus) on an extremely sodic soil with an initial pH of 10.6 and an exchangeable sodium percentage (ESP) of 94. Diplachne, Chloris and Cynodon usually gave their maximum yield in the second year of planting, P. antidotale in the third year and P. laevifolium in the fourth year. The results showed that Chloris can be recommended for such situations as it maintains a higher productivity over a longer period than the other grasses. Alternatively P. antidotale and P. laevifolium can be planted in association with Diplachne to provide a steady forage supply for a long time. Increasing doses of gypsum resulted in decreases in soil pH, exchangeable sodium and ESP and increases in calcium, magnesium, organic carbon and the infiltration rate of soil.