This study is the first time report of utilization of Trichoderma spp. isolated from different tree bark from Odisha state of India for rice crop health management and higher productivity. Six isolates of Trichoderma spp. were identified based on the morphological characteristics and species determination was performed by molecular assays. One of the isolated strains determined as Trichoderma erinaceum outperformed others. Trichoderma erinaceum controlled three soil borne plant pathogens i.e. Rhizoctonia solani, Sclerotium rolfsii and Sclerotium oryzae effectively under controlled condition and R. solani and Helminthosporium oryzae under filed condition. Seed treatments with the formulated isolates improved the germination rate of rice and enhanced vigour. These parameters along with higher chlorophyll content could be related to higher yield observed in two rice varieties; Karuna and Sahabhagidhan. Among the six isolates tested, Trichoderma erinaceum treatment recorded highest yield. Significantly higher expression of some stress related enzymes was observed in Trichoderma treated plants which helped in better crop growth both under biotic and abiotic stresses. These isolates helped both the varieties to accumulate more nutrients. This study proves that Trichoderma erinaceum obtained from tree bark may be incorporated in integrated rice crop management both as biocontrol agent and biofertilizer.

Withania somnifera (L.) Dunal (family: Solanaceae), commonly known as "Indian Ginseng", is a medicinally and industrially important plant of the Indian subcontinent and other warmer parts of the world. The plant has multi-use medicinal potential and has been listed among 36 important cultivated medicinal plants of India that are in high demand for trade due to its pharmaceutical uses. The medicinal importance of this plant is mainly due to the presence of different types of steroidal lactones- withanolides in the roots and leaves. Owing to low seed viability and poor germination, the conventional propagation of W. somnifera falls short to cater its commercial demands particularly for secondary metabolite production. Therefore, there is a great need to develop different biotechnological approaches through tissue and organ culture for seasonal independent production of plants in large scale which will provide sufficient raw materials of uniform quality for pharmaceutical purposes. During past years, a number of in vitro plant regeneration protocols via organogenesis and somatic embryogenesis and in vitro conservation through synthetic seed based encapsulation technology have been developed for W. somnifera. Several attempts have also been made to standardize the protocol of secondary metabolite production via tissue/organ cultures, cell suspension cultures, and Agrobacterium rhizogenes-mediated transformed hairy root cultures. Employment of plant tissue culture based techniques would provide means for rapid propagation and conservation of this plant species and also provide scope for enhanced production of different bioactive secondary metabolites. The present review provides a comprehensive report on research activities conducted in the area of tissue culture and secondary metabolite production in W. somnifera during the past years. It also discusses the unexplored areas which might be taken into consideration for future research so that the medicinal properties and the secondary metabolites produced by this plant can be exploited further for the benefit of human health in a sustainable way.

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Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (Xoo) is a major threat to rice production as it accounts for loss up to 50% of annual rice grain yield. Xoo causes leaf tissue necrosis and as a result there is downregulation of the photosynthetic mechanisms of plant. Measurement of chl a fluorescence is an easy, fast, non-invasive and highly sensitive technique that can be used to understand plant health by measuring alterations in PSII activity, in response to different biotic and abiotic stresses. In the present investigation, rice seeds were bio-primed with two bacterial spp. (e.g. Bacillus subtilis and B. megaterium) and one fungal strain (i.e. Trichoderma erinaceum). The induction of defence against BB disease by bio-priming with biotic agents, was studied as response in alteration of PSII and defence enzymes activity. Field experiment was conducted with the best biotic agent; i.e. B. subtilis obtained from all experiments to study whether defence induction by it have any side effect on rice yield and biomass. Net house and field experiments have suggested that among all the biotic agents studied, bio-priming of rice seeds with B. subtilis has protected the photosynthetic machinery of plants from being damaged by BB without having any detrimental effect on rice grain yield.

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Bacterial leaf blight (BLB) is a serious threat for rice (Oryza sativa L.) cultivation caused by the bacterial pathogen Xanthomonas oryzae pv. oryzae. The pathogen mainly damages the leaf chlorophyllous tissue, resulting in poor photosynthesis and causing up to 50% reductions in grain yield. In the present work, we have compared the structural and functional ability of the chloroplast of three varieties of rice with different degrees of susceptibility (TN1, highly susceptible; IR-20, moderately resistant; DV-85, resistant to BLB) treated with riboflavin (1 and 2 mM) and infected with BLB, with chlorophyll fluorescence as a tool. As indicated by the chlorophyll fluorescence technique, the disease progress curve and yield data, riboflavin acted as an effective vitamin for inducing resistance against BLB. Plants treated with riboflavin showed improved PSII activity, more chlorophyll content and higher yield than the diseased plants.