Glycine betaine mediated disease resistance against Sclerospora graminicola in Pearl Millet

Abstract

The present findings on Glycine betaine provides significant perception on the dynamics of pearl millet by activating the host defense responses during its interaction with the pathogen. Glycine betaine treatment to seeds at 30 mg ml -1 concentration for 6 h significantly enhanced the seed germination and seedling vigor of pearl millet in comparison with the control. Significant inhibition of sporangial sporulation, zoospore release and motility was observed at 30 mg ml -1 , even though it failed to exhibit complete inhibition in all the concentrations tested. TTC assay confirmed the declined release of sporangiospores from sporangia by inhibiting the viability of sporangiospores. Inducer treated seedlings recorded an early and increased hypersensitive response as a reaction to Sclerospora graminicola inoculation compared to untreated. The effect of Glycine betaine was tested by seed treatment alone, seed treatment + foliar application and foliar application alone. Significant inhibition of disease control was noticed in seed treatment followed by foliar application with 19.2% disease incidence at 30 mg ml -1 . Spatio-temporal studies indicated that seed treatment with Glycine betaine increased disease protection three days after inoculation. With these results, Glycine betaine has been shown to be an effective compound for the control of downy mildew disease in pearl millet.

Improving Regulation of Enzymatic and Non-Enzymatic Antioxidants and Stress-Related Gene Stimulation in Cucumber mosaic cucumovirus-Infected Cucumber Plants Treated with Glycine Betaine, Chitosan and Combination

“…LOX also increased after CMV infection and treatment with GB and CHT. Similar results reported by Lavanya and Amruthesh [42] found that exogenous application of GB against Sclerospora graminicola in Pearl Millet inducing LOX expressions for protecting pathogen which could lead to desaturation of lipid peroxidation products by increasing membrane stability and genes involved in stress defense mechanism via the octadecanoid pathway.…”

“…In general, plants can tolerate the diseases infection through a wide range of cellular processes; (i) up-or down-regulation of different genes; (ii) changes in pathway levels of various compounds, like reactive oxygen species (ROS); (iii) stimulation of various transcription factors activity, regulation of defense genes and pathogenesis related proteins, (iv) stimulation of protective signaling enzymes and phytohormones such as SA, JA, auxins, cytokinins, abscisic acid and gibberellic acid [40,41]. The present findings show that GB and CHT can protect cucumber plants against CMV not only by the reduction of symptom and disease severity, but also by decreasing viral titer [42].…”

“…The antiviral effect of GB and CHT appears to involve direct inhibition of virus replication or indirectly through inducing systemic resistance of the host plant against the virus [27]. One consequence of application of GB and CHT is an increase in plant growth under control (Figure 2), even in plants under stress, indirectly because of their high anti-pathogenic activity and directly through the (i) stimulation phytohormones biosynthesis, (ii) stimulation of absorption and solubilization of soil nutrients, (iii) stimulation the hardness of roots and their growth, (iv) improvement the carbohydrate metabolism levels and photosynthesis [28,42].…”