A total of 137 actinomycetes, isolated from 25 different herbal vermicomposts, were characterized for their antagonistic potential against Macrophomina phaseolina by dual-culture assay. Of them, eight most promising isolates (CAI-17, CAI-21, CAI-26, CAI-68, CAI-78, KAI-26, KAI-27 and MMA-32) were characterized for the production of siderophore, chitinase, protease, hydrocyanic acid (HCN), indole acetic acid (IAA) and further evaluated for their antagonistic potential against M. phaseolina by blotterpaper assay and in greenhouse. All the eight isolates produced HCN and IAA, seven produced siderophore (except CAI-78) and protease (except KAI-27) and four produced chitinase (CAI-26, KAI-26, KAI-27 and MMA-32). In the blotter-paper assay, no charcoal-rot infection was observed in KAI-26 and KAI-27-treated sorghum roots, indicating complete inhibition of the pathogen, while the other isolates showed 47 to 88% lesser charcoal-rot infection compared to the control. In the antifungal activity test against M. phaseolina (in greenhouse on sorghum), all the isolates increased in shoot dry mass by 28 to 53% and root dry mass by 5 to 21%, over the control. In order to confirm the plant growth promoting (PGP) traits of the isolates, the green house experiment was repeated, but in the absence of M. phaseolina. The results further confirmed the PGP traits of the isolates as evidenced by 15 to 34% increase in shoot dry mass on six isolates (except CAI-26 and KAI-27), 14 to 57% increase in root dry mass on five isolates (except CAI-68, KAI-26 and KAI-27), 17 to 60% increase in root length on five isolates (except CAI-17, CAI-21 and CAI-68) and 10 to 64% increase in root volume on six isolates (except CAI-17 and CAI-68). Culture filtrate of three potential actinomycetes (CAI-21, CAI-26 and MMA-32) at 0.5% inhibited the growth of M. phaseolina, indicating that the metabolites of these actinomycetes were responsible for the inhibition. The sequences of 16S rDNA gene of the isolates matched with Streptomyces but with different species in BLAST analysis. This study indicates that the selected actinomycetes have the potential for PGP and control of charcoal-rot disease in sorghum.

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Helminths infections are also among the most common infections in human, affecting a large proportion of the world's population in developing countries and produce a global burden of disease. Pherithema posthuma a helminthes is commonly known as earth-worms, Leucas aspera herb is distributed throughout India. the anthelminthic property of Leucas aspera was evaluated using Pherithema posthuma as an experimental model. Piperazine citrate was used as the standard reference. earthworm belonging to control group showed paralysis time as 64.33 min and death time as 200 min. Among the various concentrations of aqueous extract tested, concenration at 250 mg/ml showed efficient anthelminthic activity and among all the concentrations ethanol extract tested, concentration at 250 mg/ml gave significant results. This investigation revealed that ethanol extract of Leucas aspera showed significant anthelminthic activity against Pheretima posthuma when compared aqueous extract. Ethanol extract also proved to be efficient than the standard drug. this investigation supported the ethnomedical claims of Leucas aspera as anthelminthic plant.

Stem rot of groundnut caused by the soilborne pathogen Sclerotium rolfsii can cause significant yield losses. Biological control of stem rot using actinomycetes is a viable alternative to existing fungicidal management. Though actinomycetes are prolific antibiotic producers, reports pertaining to their use in groundnut disease management are limited. Here, actinomycetes were isolated from groundnut rhizospheric soils and screened for antagonism against S. rolfsii through a dual culture assay. Culture filtrates and crude extracts of the potential candidates were screened further for extracellular antifungal activity and characterized for biocontrol and plant-growth-promoting traits. A promising candidate was tested under greenhouse conditions as whole organism as well as crude extracts. Isolate RP1A-12 exhibited high antagonism against S. rolfsii in dual culture assay (69 % inhibition), culture filtrate assay (78-100 % inhibition at various concentrations) and crude extract assay (100 % inhibition with 1 % crude extracts). Moreover, germination of sclerotia of the test pathogen was inhibited with 1 % crude extracts. Strain RP1A-12 produced hydrogen cyanide, lipase, siderophores and indole acetic acid. Oxalic acid production by S. rolfsii was also inhibited by crude extracts of RP1A-12. In greenhouse studies, RP1A-12 reduced stem rot severity. Overall, our results suggest that isolate RP1A-12 has potential biocontrol capabilities against stem rot pathogen. Molecular characterization based on 16S rRNA gene sequencing of RP1A-12 identified it as a species of Streptomyces, closely related to S. flocculus.