Effect of mushroom (Pleurotus tuber-regium) inoculums on crude oil polluted soils on stover and grain yields of maize (Zea mays l.) In Niger-delta, Nigeria
Pollution of soils by crude oil in Niger-Delta of Nigeria has brought untold hardship to the inhabitants of the region. This study was carried out in 2010/2011 and 2011/2012 to determine the effect of Pleurotus tuber-regium (mushroom) inoculums on crude oil polluted soil on stover and grain yields and as well as cob length and circumference of maize in Emu - Ebendo, Nigeria. The soils were polluted with crude oil at different levels (0 %, 3.0 %, 6.0 % and 9.0 %) by weight of the soil (20 kg) at 0, 2 and 4 weeks duration in the soil. The soils were inoculated with mushroom at 0 g, 150 g, 300 g and 450 g and were incubated for 6 months. The experiment was a 4 x 3 x 4 factorial in a randomized complete randomized design with four replicates. Two (2) seeds of maize were planted. At maturity the maize stalk (stover), cob and grain yield were harvested for stover yield, cob length and circumference and dry grain yield. The results obtained revealed the higher the crude oil application to the soil, the lower the stover yield, grain yields, cob length and cob circumference of maize in the order of 0 % > 3 % > 6 % > 9 %. The application of crude oil at 9% on 0 – 4 weeks of oil duration in the soil, resulted in no stover yield, grain yield, and cob length and cob circumference of maize. The application of different weights of mushroom inoculum to varying levels of crude oil polluted soil significantly (P < 0.05) increased the stover yields, cob’s length, cob’s circumference and grain yields of maize except at 150 g of mushroom application on 9 % level of crude oil pollution at 4 weeks of oil duration in the soil. Conclusively, the application of mushroom at varying levels in crude oil polluted soil increased the stover and grain yields and as well as of cob length and circumference of maize.
Keywords: Crude oil, soil, mushroom, performance characteristics