Response of Maize (Zea mays) to VAM Inoculation as Affected by Different Levels of Rock Phosphate Application

Abstract

To test the effects of rock phosphate levels (0, 100, 200, 300 and 400 kg/ha) and VAM inoculation on maize, the greenhouse experiments were carried out in sandy soil. The results revealed that the maize positively responded to the rock phosphate levels and VAM inoculation. The total root length, total dry matter, P and K uptake of most plants were increased as P increased in both non VAM and VAM plants but VAM colonization were decreased as P increased. The maximum VAM colonization on the maize root, 31.80%, was found in the plants inoculated with VAM but no P application. Positive effect of VAM on maize growth in most treatments were shown at 10 weeks but not at 6 weeks. The VAM plants applied with 200 kg/ha of rock phosphate had maximum total dry matter, P uptake and K uptake (136.65 g/plant, 45.93 mg P/plant and 406.63 mg K/plant, respectively) which were higher than both non-inoculated plant at the same rock phosphate application level (10.00, 31.64 and 26.85%, respectively) and those of non-inoculated plant without rock phosphate application (286.72, 591.72 and 66.71%, respectively).