Previous studies have described the development of control methods against bacterial wilt diseases caused by Ralstonia solanacearum. This review focused on recent advances in control measures, such as biological, physical, chemical, cultural, and integral measures, as well as biocontrol efficacy and suppression mechanisms. Biological control agents (BCAs) have been dominated by bacteria (90%) and fungi (10%). Avirulent strains of R. solanacearum, Pseudomonas spp., Bacillus spp., and Streptomyces spp. are well-known BCAs. New or uncommon BCAs have also been identified such as Acinetobacter sp., Burkholderia sp., and Paenibacillus sp. Inoculation methods for BCAs affect biocontrol efficacy, such as pouring or drenching soil, dipping of roots, and seed coatings. The amendment of different organic matter, such as plant residue, animal waste, and simple organic compounds, have frequently been reported to suppress bacterial wilt diseases. The combined application of BCAs and their substrates was shown to more effectively suppress bacterial wilt in the tomato. Suppression mechanisms are typically attributed to the antibacterial metabolites produced by BCAs or those present in natural products; however, the number of studies related to host resistance to the pathogen is increasing. Enhanced/modified soil microbial communities are also indirectly involved in disease suppression. New promising types of control measures include biological soil disinfection using substrates that release volatile compounds. This review described recent advances in different control measures. We focused on the importance of integrated pest management (IPM) for bacterial wilt diseases.

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Isolation of endophytic fungi was done to find alternative microorganisms as biocontrol agents against Rhizoctonia solani Kuhn, a soil borne pathogen on many agriculturalcrops. The research objectives were 1) to isolate and identify endophytic fungi colonize plants growing on agricultural and Mount Salak supporting forest lands in the Villages of Parakan Salak and Cimalati, Sukabumi; and 2) to screen for their biocontrol agent activity againt R. solani. Diameter of R. solani was measured on day 2 after inoculation, and its percent inhibition of growth by endophytic fungi is calculated using the formula Skidmore & Dickinson (1976). The results indicated that 214 isolates of endophytic fungi were isolated from 96 plant species that growing in both places. Endophytic fungi isolated including in the group of Aspergillus, Cladosporium, Colletotrichum, Curvularia, Drechslera, Fusarium, Guignardia, Mucor, Nigrospora, Paecilomyces, Penicillium, Pestalotiopsis, Phoma, Phomopsis, Rhizoctonia, and endophytic fungi that have not been identified. Of the 214 fungal isolates tested, 39 isolates (18.22 %) could inhibit the growth of R. solani from 10.18 % to 58.99 % with a percent inhibition. The highest growth inhibition of R. solani were shown respectively by an unidentified fungus isolatedfrom Hyptis capitata Jack (58.99%), Cladosporium sp. isolated from jeruk bali (Citrus grandis (L.) Osbeck) (55.42%), Pestalotiopsis sp. isolated from pine apple (Ananas comosus (L.) Merr.) (53.85 %), and Paecilomyces lilacinus (Thom) Samson isolated from banyan (Ficus benyamina L.) (51.81%)

Biocontrol activity of Enterobacter cloacae alone and in combination with copper and mangan on the suppression of tomato damping off was assessed. Rhizoctonia solani damping-off is difficult to control, since its dorman organ sclerotia survive for long periods under various environmental condition. The availability of micronutrients copper and mangan may play important roles in controlling of plant diseases. Results showed that the application of E. cloacae alone decreased damping-off of tomato significantly (P<0.05) by 85%. Combination application of E. clocae with 10μg ml−1 of CuSO4 showed the highest suppression of the disease, followed by the treatment of E. cloacae with 5μg ml−1, as high as 95% and 90% respectively, although the differences was not significant compared to other treatments. Degree of the disease suppression did not differ between application of E. cloacae alone and in combination with both concentration of MnSO4 (μg ml−1 and10μg ml−1), the disease decreased about 85%. Inoculation of R. solani alone into soil resulted significantly highest (P<0.05) of fungal population, it was about 33.7 x 103 CFU g−1 soil, and inoculation of R. solani and E. cloacae reduced significantly fungal population to about 19.0 x103 CFU g−1 soil. E. cloacae produced chitinase and protease, its chitinolytic index was about 0.84, and proteolytic index was 0.61.