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Sclerotium rolfsii Sacc causes serious yield loss of Pippali (Piper longum Linn.). Catkin, the fruit of Pippali is directly used in medicinal industry so, use of chemical fungicides is not encourages for the cultivation of Pippali. The present study was carried out to bring orgnaic management strategy of the crop. Six native isolates of fungal and bacterial antagonists were tested against S. rolfsii and found T. harzianum was found as the best agents. In in vitro studies, sclerotial production was found drastically reduced when exposed to biocontrol agents. Result on field experiment showed that soil application of mustard oil cake (MOC) @ 1 kg/2X2 m2 plot fortified with T. harzianum @ 5 ml/m2 found effective in managing the basal rot with disease reduction upto 10.65% with increased plant growth parameters. This was followed by soil application of T. harzianum @ 5 ml/m2 with disease incidence of 14.98%.

Biological control of plant pathogens has become increasingly possible with the use of fungi, which have a high reproductive rate (both sexually and asexually) and a short generation time and are very specific to their target. Trichoderma species are found in diverse habitats and experience various interactions with other organisms. They are used as bio-fungicides owing to their plant-protecting abilities, and they produce a large number of secondary metabolites (SMs) accompanied by enrichment in secondary metabolism-associated genes. This article aims to review and discuss the SMs produced by Trichoderma species, including their physiology, mode of action, mass production, and industrial and field applications for the control of plant diseases. We also discuss the evolutionary history, taxonomical gradient, classification, and ecology of Trichoderma species, as well as indirect and direct mechanisms used as plant protectors with gene improvement strategies. Aside from the bioactivity of SMs derived from Trichoderma species, compatibility with fungicides, mass formulation techniques, and industrial applications of Trichoderma species, the review focuses on its advent and progress as a global research pioneer.

Beauveria bassiana (Balsamo) Vuillemin, a white muscardine fungus has widely drawn attention of crop protection practitioners as potential biocontrol agent against insect-pests since decades. In the present study, antagonistic potential of 22 native of B. bassiana isolates were evaluated against damping-off disease of tomato caused by Pythium sp. Results showed that all B. bassiana isolates were able to inhibit mycelial growth of P. myriotylum to the extent of 68–82%. Further studies were conducted to understand the ability of screened B. bassiana isolates to produce cell wall degrading enzymes (CWDEs) viz., amylase, caesinase, chitinase, cellulase, lipase and protease respectively. The potential B. bassiana isolates showed dynamic colonization efficiency in tomato plants with colonization percentage (%) as high as 72–80% through seed inoculation. Eventually, potential isolate BP1.1 has showed wide pH tolerance ability ranging from pH 6–10. Further, potential isolate B. bassiana BP1.1 was evaluated for their efficacy against damping off of tomato under in vitro condition yielding higher germination percentage of 87.34% of and lower disease incidence up to 33.45% under treatment combinations. These findings provide substantial evidences on multifarious potential of B. bassiana as antagonist as well as plant growth promoter in addition to a potential entomopathogen, thus paves the way of a newer domain in the arena of crop protection.

In the present study, chitosan nanoparticles were synthesized from four different fungal sources viz., Fusarium oxysporum, Metarhizium anisopliae, Beauveria bassiana and Trichoderma viride and from one commercial source of chitosan.UV–VIS spectroscopy study of synthesized nanoparticles showed absorption peaks at the range of 310.02 to 342.00 nm. Functional groups of chitosan nanoparticle as OH, N–H, C–H, C=O, C–O, C–N and P=O were confirmed by FTIR study. Surface properties of the synthesized nanoparticles were found to be positively charged and were found stable in nature. Electron microscopy study showed that synthesized nanoparticles are nearly spherical in shape. DLS analysis showed the average size of the chitosan nanoparticles synthesized from F. oxysporum, M. anisopliae, B. bassiana, T. viride and commercial products as 273.20, 172.50, 78.36, 89.03 and 300.10 nm respectively. Compatibility study of chitosan nanoparticles with T. asperellum showed highly compatible reaction with chitosan nanoparticles at the tested concentration. In vitro assay against Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii showed combination of T. asperellum and chitosan nanoparticle as superior in suppression of mycelial growth of the pathogens as compared to Trichoderma alone and carbendazim @0.1%.

In this experiment an effort was made to synthesize silver nanoparticle biologically from Trichoderma asperellum, a potential indigenous biocontrol agent. Silver nitrate was added as precursor for the synthesis of silver nanoparticle. The biosynthesized silver nanoparticle was characterized by UV–Vis spectrophotometer, dynamic light scattering (DLS), X-ray diffraction (XRD), zeta potential and transmission electron microscope (TEM). UV Vis spectrum of aqueous medium containing silver ion showed peak at a wavelength of 420 nm corresponding Plasmon Absortion of silver nanoparticle. DLS study showed that the biosynthesized silver nanoparticles have a size of 27.64 nm with polydispersity index (PDI) of 0.409. The charge of silver nanoparticle was determined by zeta sizer and found to have negative potential value of − 1.34. It indicates that the biosynthesized nanoparticle are stable on dispersion. TEM study revealed the formation well dispersed silver nanoparticle in the range of 9–41 nm with roughly spherical in shape. Fungicidal activity of silver nanoparticle at different concentration (100 ppm, 50 ppm, 30 ppm, and 10 ppm) tested against four soil borne plant pathogens viz., Rhizoctonia solani, Fusarium oxysporum, Sclerotinia sclerotiorum, and Sclerotium rolfsii and comparison was made with Carbendazim @3000 ppm. The result showed that the silver nanoparticle at 100 ppm showed significantly higher efficacy in inhibiting mycelial growth of the pathogens as compared to the Carbendazim at 3000 ppm.

Morphological changes in Metarhizuim anisopliae (Metschnikoff) Sorokin infected cow pea aphid, Aphis craccivora Koch were studied by scanning electron microscope (SEM). Aphids were caged on paired lantern chimney over cowpea twigs dipped in conical flasks with water infected and inoculated with fungal propagules of M. anisopliae at the concentration of 1X106 spores /ml of water. Infected aphids were observed under SEM and it showed severe cuticular damage, abnormalities in sensory systems as well as deformation of all the body parts. The hydrophobic conidia of M. anisopliae were found to attach to all body regions. It was evident that mycelial growth and conidiophores with conidia of M. anisopliae covered the body surface and penetrates inside the body of infested aphid causing damage to the pest by disturbing its major physiological activities leading to its death.

Metarhizium anisopliae is among the ubiquitous members of the soil rhizosphere which also survives as an endophyte in a wide range of plants. The extent of colonization depends on the plant part evaluated and inoculation method used. Current research reveals that foliar spray favours leaf colonization, whereas soil drenching favours root colonization. Besides M. anisopliae, many other fungal isolates were recovered as endophyte which was found to be endosymbiont with each other. Infestation of aphid, Toxoptera aurantii; tea mosquito bug, Helopeltis theivora; termite, Odontotermes obesus; red spider mite, Oligonychus coffeae and carpenter worm, Prionoxystus robiniae was found less in the treated plot as compared to the untreated control. System season long endophytic colonization with the plants suggests a novel approach of biological control of these pests via foliar spray with M. anisopliae for aerial pests and soil drench for soil arthropods. The same entomopathogen was also further confirmed by light and electron microscopic techniques inside the host plant. Molecular study showed that the original culture and endophytic reisolated culture of M. anisopliae were 100% identical to each other.