The effect of some organic substances and the concentration of dayizone pesticide on the composition and microbial activity of soils

Abstract

The present study has been conducted to investigate the effect of organic substance of klkoz and the clover added to the soil on the decomposition of dayizon pesticide in the soil , and the effect of this on the microbial activity of microorganisms in addition of the organic Carbon ,Nitrogen and Phosphorus in the soil –A type of mixed soil was used in the study – It was brought from an agricultural field in the city of Ramadi in which no type of pesticides had been used for a period of more than ten years . The organic substance of klkoz and the dry clover remaining had been added and cultivated well in the soil at a ratio of %1 for all treatments. Three concentrations(0, 250,500) ML.100L. Donam had been added to the soil according to the treatment. All these treatment had been incubated at a tempreture%28 for(20,40,60)days. Then, the total number of microbe, fungi, Actinomycetes ,Bacteria solvent for phosphate ,cellulose decomposing Bacteria, Aozossberellim Bacteria , and the Azutobkatr Bacteria were estimated in the soil .Besides, the Nitrogen, the organic carbon, and phosphor , were also estimated in the soil under study .The results revealed that the addition of the organic substance has a great role in the increase of different races of microorganism in the soil and in the decrease in the inhibitory effect of pesticide under study . It was indicated that there was a differentiated effect of adding an organic substance to the soil at %1. This led to an increase in the total numbers of the treatment that used a pesticide . The numbers reached the higher level after a period of incubation of (60) days on the other hand , when the pesticide used without an organic substance , the effect was higher that the total numbers of microbe decreased differently according to the difference in the concentration used and the period of incubation , so that difference between the treatment of comparison and au treatments of the pesticide was significant from the period of incubation (20) days until the end of the experiment (60) days . This recorded the less effect of the recommended dose of the used pesticide on the other hand the effect was inhibitory , signification and clean when using a double dose of pesticide recommended in the field. The decrease in the numbers as a result of using the pesticide with the existence of the or organic substance was little ,and this indicates that using the organic substance kolkhoz and clover led to a decrease in the effect inhibited to the pesticiot on the total number of microbe especially used in the case of uling a double close of pesticide used in the study . At the end of the experiment ,it was showed that the inhibitory effect, during a period of incubation and to days, was clearly least at using the organic substance with the three concentrations of pesticide. The result, also rescaled that the Nitrogen .and phosphorus in the soil reached the higest value after a period and (60)days and incubation in the treatment in the which the organic substance was used without wing the pesticide. But when the pesticide was used without the existence y the organic substance, the effect on the Nitrogen and phosphor was higher. The fixed effect was little especially at using the organic substance on the pesticide with all its three concentrations. whilst ,it is found that the organic carbon in the soil decreased gradually with the increase of the in cubation .Period. This is due to activity of the microbe in the soil