PHYSICO-CHEMICAL AND BIOLOGICAL CHARACTERIZATION OF THE COMPOST E2 AND THEIR POTENTIAL FOR SUPPRESSING PLANT DISEASES

Abstract

Composting is a natural degradation process of organic matter. Thus, this practice is promising in terms of economy and environment. Another intriguing aspect of this practice is the protection of plants from fungal diseases. The ultimate goal of this study is to check the efficacy of the compost and their potential for suppressing plant diseases. Our product (E2) has been produced by the mixing of 50% of green waste and 50 % of sheep manure. In addition, Trichoderma sp was supplemented to improve the value of this biological alternative in agriculture. On the other hand, we have also produced the compost extract for two main purposes; the former is to evaluate the physicochemical and biological proprieties, the latter is to examine their effect in controlling pathogenic fungi (Fusarium solani, Fusarium acuminatum, Alternaria sp) in vitro and in vivo. The biological analysis of our compost has clearly demonstated different genres of microbial population in our compost. In physicochemical test, we have also recorded a good biodegradation of organic matter, an alcaline value of pH and a richness of humic and fulvic acids. Then the presence of fertilizing elements has followed. The mediums were prepared from the compost extract with glucose autoclave and without glucose autoclave-free at 120°C and 80°C. After that, they were tested on biological characters in vitro of the fungi tested. Both medias have depicted significant results in inhibiting the mycelial growth, sporulation and the germination on the tested pathogens. The medium of compost extract without glucose resulted maximum inhibition in mycelial growth by (90%), sporulation and spore germination by (85%).To evaluate the effect of compost and their extract in vivo for the protection of tomato plants from fungal diseases, of 50% from the compost E2 was added to the substrate contaminated by the telluric pathogen (Fusarium solani and Fusarium acuminatum). Such addition has manifested the minimization of the disease incidence up to 25% compared to the control. Similar result has been observed for the leaf disease (Alternaria sp). As a final vital remark, preventive control by compost extract is the best method to reduce the foliar disease incidence compared with the curative control.