ABSTRACT
Two field experiments were carried out, in two different texture locations at the Agricultural Experimental Station of El-Kharga, New Valley Governorate, during two successive seasons, to study the effect of organic manuring [Multhum] in different doses [0, 2, 4, 8 t/fed.] and two irrigation intervals [14 and 21 days] on the microbiological and enzymatic activities under wheat, and their effects on wheat yield. The results showed that the application of organic manure did not increase the biological activities under wheat after the end of the first year, while its positive effect was clarified at the end of the second year, measured by the noticeable increase in the counts of total bacteria, streptomyces and aerobic cellulose decomposers, as well as the enzymatic activity. The elongation of the irrigation interval had a negative effect on the biological activities under wheat during the course of the experiment and also significantly decreased plant height, leaf area and the yield of wheat in both types of soil under study. It seems that the irrigation interval [14 days] was the most favorite for biological activity in soil