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Maize is an important cereal crop which is severely affected by Spodoptera frugiperda . The study aims to identify endophytic bacteria of maize root and leaf apoplastic fluid with bioprotective traits against S. frugiperda and plant growth promoting properties. Among 15 bacterial endophytic isolates, two strains-namely, RAF5 and LAF5-were selected and identified as Alcaligenes sp. MZ895490 and Bacillus amyloliquefaciens MZ895491, respectively. The bioprotective potential of B. amyloliquefaciens was evaluated through bioassays. In a no-choice bioassay, second instar larvae of S. frugiperda fed on B. amyloliquefaciens treated leaves (B+) recorded comparatively lesser growth (1.10 ± 0.19 mg mg -1 day -1 ) and consumptive (7.16 ± 3.48 mg mg -1 day -1 ) rates. In larval dip and choice bioassay, the same trend was observed. In detached leaf experiment, leaf feeding deterrence of S. frugiperda was found to be greater due to inoculation with B . amyloliquefaciens than Alcaligenes sp. The phenolics content of B. amyloliquefaciens inoculated plant was also found to be greater (3.06 ± 0.09 mg gallic acid g -1 ). However, plant biomass production was more in Alcaligenes sp inoculated treatment. The study thus demonstrates the potential utility of Alcaligenes sp. and B. amyloliquefaciens for improving growth and biotic ( S. frugiperda ) stress tolerance in maize.

An endophytic fungal antagonist Trichoderma longibrachiatum EF5 exhibited biocontrol activity against a soil-borne fungal pathogen Macrophomina phaseolina. Under dual co-culture, T. longibrachiatum EF5 showed 58% inhibition against M. phaseolina. Crude soluble metabolites (SMs) extracted from EF5 exhibited biocontrol activity (61%), which is more significant than the cell-free extract. Dual culture of both T. longibrachiatum EF5 and M. phaseolina displayed entangled mycelial structures and retarded hyphal growth. The metabolites responsible for antibiosis and pathogenic activity profiled through GC-MS revealed a total of 131 SMs from axenic culture and upon the interaction of T. longibrachiatum EF5 and M. phaseolina. Interestingly, potential plant-growth-promoting and antimicrobial compounds such as 1- pentanol, 1-hexanol, myristonyl pantothenate, bisabolol, d-Alanine, and diethyl trisulphide were unique with T. longibrachiatum EF5. Few compounds that were not observed or produced minimally under axenic culture were increased during their interaction (e.g., 1,6-anhydro-á-d-Glucopyranose and 5-heptyl dihydro-2(3H)-Furanone), suggesting antimicrobial action against the pathogen. This study also unraveled the induction of amino sugar metabolism when T. longibrachiatum EF5 interacts with M. phaseolina, which is responsible for colonization and counterfeiting the pathogen. Hence T. longibrachiatum EF5 could be a potential biocontrol agent employed for defense priming and plant growth promotion., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Today, many researchers are focusing on research for alternative promising energy sources and sustainable technology for bioethanol production to meet the increasing global energy demand. Here, we develop a novel one-pot pretreatment technology by co-immobilizing laccase, cellulase and β-glucosidase to act as a tri-enzyme biocatalyst for evaluating the bioethanol production potential of four sustainable lignocellulosic biomasses viz., Typha angustifolia, Arundo donax, Saccharum arundinaceum, and Ipomoea carnea. The co-immobilized enzyme system was more stable at different temperatures and at longer storage, compared to free enzyme. During enzymatic saccharification, Saccharum arundinaceum showed higher total reducing sugar of 205 ± 3.73 mg/g when compared to other biomass. The highest percentage of bioethanol yield of 63.43 ± 9.35% was obtained with Ipomoea carnea. The effects of co-immobilized tri-enzyme biocatalyst on the biomasses were evaluated. The results revealed that the co-immobilized tri-enzyme biocatalyst could act as effective one-pot pretreatment for the production of bioethanol from lignocellulosic biomass., (Copyright © 2018 Elsevier Ltd. All rights reserved.)