PHYTOTOXICITIES OF ALANG-ALANG (COGON GRASS) RESIDUE AND RICE STRAW ON LAMTORO

Abstract

An experiment was conducted to determine the phytotoxicity of rhizome of alang-alang (Imperata cylindrica) and rice straw incorporated into the soil on the dry yields of of Leucaena leucocephala. Oven dried rhizomes of Imperata and sun dried rice straw were cut into small fragment and then incorporated into the clay loam soil at the rates of 0, 2 and 4 % (w/w) Pots of soil – plant residues mixture were incubated in Phytotron room at 25o C and 70 % relative humidity for one, two, three and four months. Residues was tested against Leucaena seeds. Results showed that as increasing plant residues level and decreasing length of decomposition period, shoot dry weight in Leucaena decreased. There was no significant difference (P > 0.05) between effects of decomposing residues of Imperata and rice straw on shoot dry weight in Leucaena.