Determination of effects on solid and liquid humic substances to plant growth and soil micronutrient availability

Abstract

Two experiments were conducted to determine the optimum application levels of solid and liquid humic substances. First experiment comprised effects of humic substances on dry weight with some nutrient element uptake of plant. Second experiment comprised five rates of solid and liquid humic substances were added to the soil at four incubation periods. At the end of the first experiments, dry weight, N, P, K, Cu and Zn uptake were relatively affected by solid humic substance application. Moreover, dry weight, K, Zn and Fe uptake were relatively affected by liquid humic substance application. However, N and P uptake of plant was not affected by humic acid treatments. The available micronutrients contents of the soil were found higher at first incubation period than in other periods. Most suitable application dose of solid humus was 0.5-1 g kg(-1). However, most of suitable liquid humic acid application dose must be determinated.