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2016 - 201912020 - 20221
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Subject: Plant Physiology × Author: Yadav, Ritika × Start date: 2015 × Type: Thesis ×
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    ThesisItemOpen Access
    Elucidating the effect of potassium silicate and salicylic acid on morphological, physiological and biochemical aspects of mango (Mangifera indica L.) malformation
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2022-01) Yadav, Ritika; Bains, Gurdeep
    Malformation is a one of the most threatening malady of mango (Mangifera indica L.) and responsible for great economic loss in mango growing regions. Present investigation was carried out at Horticulture Research Centre, Patharchatta and Department of Plant Physiology, College of Basic Sciences & Humanities, GBPUA&T, Pantnagar, to study the effect of foliar application of potassium silicate (KSi) and salicylic acid (SA) on malformation in two mango cultivars Amrapali (moderately susceptible) and Dashehari (moderately resistant) during the year 2018 and 2019. The experimental design was factorial randomized block design (RBD) with three replications. Nine different concentrations of potassium silicate and salicylic acid {0% (water spray), 0.25% KSi, 0.50% KSi, 1% KSi, 2% KSi, 5% KSi, 0.25% SA, 0.50% SA and 0.75% SA)} were sprayed at three different stages i.e., prior to panicle emergence, pre bloom and full bloom in the month of February to March. The effect of KSi and SA on malformation was evaluated with respect to morphological, physiological and biochemical characters. Fusarium was isolated from malformed floral tissues and characterized on the basis of purple orange colour on potato dextrose agar (PDA) media. It was observed that potassium silicate and salicylic acid treatment significantly reduces mycelial growth of Fusarium. It was also reported that foliar application of KSi and SA significantly reduces the occurrence of floral malformation as compared to control. Panicle length, flowering percentage, physiological and biochemical characteristics viz. chlorophyll fluorescence, chlorophyll content, total phenol, and total protein content significantly increased under 1% KSi followed by 0.50% SA treatments with respect to control. Several reactive oxygen species (ROS) are continuously produced in plants as by product of aerobic metabolism. Some are highly toxic and detoxified by various cellular enzymatic and non-enzymatic mechanisms. Under stress condition MDA is produced and it serves as an index of lipid peroxidation. SA and KSi treatments significantly decreased the MDA content while proline content, SOD, ascorbate peroxidase, catalase, glutathione reductase and guaiacol peroxidase activity increases in dose dependent manner. Overall findings of the present investigation suggested that pre-treatment of potassium silicate or salicylic acid at both 1% KSi and 0.50% SA could help in maintaining vital physiological and biochemical processes and induces defence response either by eliminating the active oxygen species, inhibiting the infection of Fusarium in host tissue and strengthening plant defence mechanism.
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    ThesisItemOpen Access
    Evaluation of drought tolerance in different genotypes of rice (Oryza sativa L.) under laboratory and field condition
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Yadav, Ritika; Bains, Gurdeep