ABSTRACT
Potato soft rot, caused by Bacillus pumilus Od23, greatly affect potato tuber quality in storage and cultivars of Mali and indicated that it can affect all potato cultivars. Bacteria isolated from soil rhizosphere samples of healthy Malian indigenous trees were screened for their antagonistic effect against this pathogen. Three actinomycetes isolates (RoN, G1P, and N1F) were the most effective microbioagents in suppressing the growth of the pathogen. The biological control essay showed the possibility of controlling potato soft rot by these three actinomycetes isolates under conservation conditions. These treatments significantly decreased soft rot compared with the untreated potato tuber slices. The microbiological control results of this study suggest that the actinomycetes isolates RoN, G1P and and J1N are effective microbioagents in controlling soft rot of potato and could be considered as promising alternative to chemical products.
ABSTRACT
The bacteria Thiobacillus thioparus, Thiobacillus thiooxidans and Thiobacillus ferooxidans are known to be able to oxidize elemental sulfur in soils and influence phosphorus solubilization. These bacteria can solubilize the phosphorus of apatite rock by producing sulfuric acid from the oxidation of elemental sulfur and some sulphide. We think that the capacity of these bacteria can be exploited to set up a biophosphate from Tilemsi natural rock phosphate exploited in Mali. This work aims to identify, isolate and characterize Tilemsi rock phosphate (TRP) solubilizing Thiobacillus strains in various agricultural soils. Obtained results showed that the analyzed soils are poor in Thiobacillus and that the quantity of acid produced and TRP solubilized is directly proportional to the growth of these bacteria.