Induction of defense-related enzymes, such as phenylalanine ammonia lyase (PAL), peroxidase (PO), polyphenol oxidase (PPO), superoxide dismutase (SOD) and catalase (CAT) due to bacterial antagonists viz., Pseudomonas fluorescens (Pf1) and Bacillus subtilis (EPCO16) and plant-derived lipoxygenase volatile compound hexanal, were studied in mango fruits against Lasiodiplodia theobromae causing stem-end rot disease. The results showed increased induction of all the defense-related enzymes in mango fruits 3-5 days after dipping treatment with combination of bacterial antagonists and hexanal when compared to untreated control treatment and treatment with fungicide carbendazim in storage condition. The increased activity was observed up to 3 days after treatment and thereafter declined. Further, increased expression of specific isoforms of PO, PPO, SOD and CAT were also observed in the treatment effect of P. fluorescens (0.5%) + hexanal (0.02%) treated fruits against L. theobromae. From the results obtained, it is inferred that due to the enhancement of defense-related enzymes via the phenylpropanoid pathway and due to secretion of secondary metabolites that would play significant role in hindering the pathogen quiescence and further invasion in mango fruits and thereby prevent the fruit rot.ARTICLE HISTORY

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The global COVID-19 pandemic has hit the agriculture sector hard around the world. A study was conducted to assess the impact of the pandemic on cropping patterns, crop management, usage of chemical inputs and their organic alternatives, harvesting, and marketing avenues through a survey approach in the two states of Kerala and Tamil Nadu in India. A total of 250 farmers participated in the study, the data was analyzed by Chi-square test and Kruskal–Wallis test. The assessment of the impact of COVID-19 on some aspects was undertaken by dividing the study period into three phases. Though a smaller number of people were infected with COVID-19 in the initial phase of the pandemic compared to the later phases, farm operations and the procurement of inputs were significantly affected at this phase as there was a sudden disruption in transportation due to COVID-19-induced movement restrictions. During the entire study period, commodities such as rice, bananas, vegetables, coconuts, and flowers suffered maximum crop loss compared to pulses, groundnuts, cotton, and rubber. Among fertilizers, the maximum shortage was observed for chemical fertilizers (46%) and biofertilizers (30%) compared to cow dung (18%) and poultry manure (6%), indicating that farmers tended to use more local materials that could be easily procured and accessed compared to shop-based inputs. A rise in the cost of cultivation, scarcity of farm workforce, and difficulty in hiring farm machinery all have contributed to the loss of profit during the pandemic period. As a response to COVID-19, growers initiated post-harvest processing of commodities, and cropping systems remained the same during the period. The paper also discusses some remedial measures to be adopted by households in the future, to minimize the impacts of such pandemics in the agrarian sector.

Antagonist and organic amendments based bioconsortia (seri bed waste+Pf1+Bs4+Th1+neem cake) was found to lead the restriction of Fusarium solani pathogen in mulberry roots mainly by inducing inherent defense enzymes. Induction of defense enzymes such as peroxidase, polyphenoloxidase, phenylalanine ammonia lyase, phenols, catalase and superoxide dismutase, was studied in mulberry plants pretreated with bioconsortia and comparative fungicides challenged inoculation with Fusarium solani in glasshouse condition. There was increased expression of defense enzymes in mulberry plants treated with bioconsortia, when compared to control. The bio-chemical reaction of the above defense enzymes started to increase at the 3rd day, reached maximum on the 5th day and thereafter declined gradually. The native polyacrylamide gel electrophoresis (PAGE) experiment showed that one to four isoforms of the defense enzymes each with greater intensity were expressed in these treatments. This is indicating that the restriction of F. solani in mulberry plants was mainly due to application of microbial bio-consortia.

Purpose: There is a particular paucity of information emanating from Tamil Nadu state, where organic farming appears to have a promising future. Some of the constraints revealed from primary sources suggest to the importance for a comprehensive study that would resulting in a strategic model framework for sustainable organic farming in Tamil Nadu.Research Method: Precisely, 180 organic farming practitioners from the Coimbatore, Erode, and Tiruppur districts in Tamil Nadu were selected through purposive random sampling method. A semi-structured questionnaire and a personnel interview style were used to collect data. To determine significant contributing independent variables that determine the impact of organic farming, a step-down regression approach was employed. Findings:The majorities of participants were old-aged, had undergone collegiate to secondary education, had received organic farming training, and owned low livestock. Though there was a moderate level of media exposure, extension personal interaction, risk and scientific orientation among the respondents were apparent. Farmers' perceptions about environmentally friendly conservation practices, the use of organic manures, the profitability of organic farming, and environmental degradation ranged from moderate to high levels. Independent variables accounted for 77.30 percent of the variation in organic farming's impact on farmer livelihood security. Based on these observations, a model has been proposed for designing a future strategy. Originality/ Value:The proposed model will serve as a wake-up call for policymakers and concerned officials in framing new programs from the standpoint of organic farming.