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Endophytic microbes including bacteria and fungi inhabiting in seed tissues have recently gained significant importance owing to a diversity of roles that they play and eventually resulting in improved plant growth as well as plant fitness. Some of the major roles played by seed endophytic microbes include plant growth promotion by enhanced nutrient acquisition or production of growth hormones, nitrogen fixation, phosphate solubilisation, and protection against pathogens as well as abiotic stresses. Since, rice is one of the important staple crop across the globe, there is a great need to explore and decipher the roles of the endophytic community present inside it. This chapter focuses on the diversity and distribution of rice seed endophytes, their transmission along with the various functional roles that they play inside the plants with an aim to provide deep insights on rice seed endophytes as plant growth promoting and biocontrol agents. more...

This chapter discusses the roles of seed-vectored microbes in modulating seedling development and increasing fitness of plants in terms of increased biotic and abiotic stress tolerance. Particular emphasis is placed on microbes that function in the rhizophagy cycle. These microbes have been shown to enter into root cells and stimulate root growth. In some cases microbe entry into root cells results in root growth repression. The term ‘endobiome interference’ has been applied to the phenomenon of plant growth repression due to intracellular microbes. The potential application of endobiome interference to produce bioherbicides that selectively enhance growth of target crops but inhibit competitor weeds is discussed. more...

Endophytic microbes colonize plants growing in diverse habitats and play important roles in modulating development and improving fitness of host plants. Endophytes may be major components of undiscovered microbial diversity. Further, endophytes may have applications in growth promotion of crop plants and protectors of plants from biotic and abiotic stresses. Endophytes have been a source of bioactive molecules of pharmaceutical importance. Major focus areas in the investigation of endophytes include (1) assessment of endophyte diversity, (2) determining the roles played by endophytes in modulation of host plant development and (3) assessing the biotechnological potentials of endophytes. The study of endophytes is particularly challenging because endophytic microbes often go unobserved in plants, many endophytes cannot be isolated, and plants free of endophytes sometimes cannot be obtained, making it difficult to conduct experiments. In this chapter we discuss some of the methodologies that are being used to overcome challenges to the study of endophytic microbes. more...

Recent advancement in the fungal molecular genetics has established that fungi have numerous genes or gene clusters that remain silent or unexpressed under the normal conditions. These genes can be activated through epigenetic modifiers to produce a wide range of potential bioactive metabolites of agricultural and pharmaceutical values. In this study one DNA methyltransferase inhibitor (5-azacytidine) and one histone deacetylase inhibitor (sodium butyrate) were used for the epigenetic treatment to the Colletotrichum gloeosporioides isolated from the surface-sterilized leaves of S. cumini. The crude compounds isolated from the epigenetically treated C. gloeosporioides were observed to exhibit increased antibacterial activity against human bacterial pathogens (Aeromonas hydrophila, Enterococcus faecalis, Escherichia coli, Salmonella typhi, Shigella boydii, and Staphylococcus aureus). In terms of antibacterial efficacy, the secondary metabolites extracted from the culture treated with 5-azacytidine were found to be the most effective against all the tested bacterial pathogens followed by cultures treated with sodium butyrate and the combined treatment of both 5-azacytidine and sodium butyrate compared to control except against the S. typhi. The HPLC profiling showed that fungal crude metabolite compounds from different treatments of epigenetic modulators activated the production of additional metabolites compared to the untreated control. Further, the total amount of secondary metabolites extracted with ethyl acetate from treated cultures showed severalfold increase. This indicates toward the change in the expression of some cryptic genes or gene cluster through epigenetic modification by 5-azacytidine and/or sodium butyrate treatment(s). more...