| dc.description.abstract | Application of humic substances has not been well-implemented in horticultural cultivation. In the other hand, methods on application of humic substances need to be examined due to their solubility in water and little amount required on application. The research was conducted in order to study the effect of various methods of application of humic substances on production of Ipomoea reptans Poir. in several growing seasons and also to describe their mechanism in increasing plant and soil properties. Results show that the application of humic substances carried by zeolite was the best method in increasing plant yields especially at first two planting times. This increasing was supported by stimulation in plant height, number of leaves and length of leaf. After the third planting time, there was no change in soil chemical properties affected by the treatments. The application of humic substances carried by zeolite gave more profit compared to other methods. The mechanism of increasing plant yield by the ameliorants especially resulted by enhancements in rhizosphere i.e. root biomass can uptake nutrients such as N, P, and Fe were better than in other methods. | en |
