RESPONSE OF RICE TO NANOSILICA: PHYSIOLOGICAL AND LEAF SURFACE ANATOMICAL CHARACTERS UNDER DROUGHT STRESS

Abstract

The aim of this study was to assess the effects of nanosilica on drought imposed rice plants and to evaluate the impact of different concentrations of nanosilica on growth, anatomical, physio-biochemical parameters and yield characters of rice under drought conditions. The experimentation was carried out during the summer 2020-2021 at the Rice Department of Tamil Nadu Agricultural University (TNAU), Coimbatore. Different concentrations of nanosilica formulation were used as foliar spray in this present experiment viz., 200, 400, 600, 800 and 1000 ppm under drought condition. In this present field experiment, application of 400 ppm nanosilica formulation increased leaf area and specific leaf weight with 14.3 and 15.3 percent under drought stress. Application of 400 ppm nanosilica increased up to 12.5 percent in terms of Menbrane Stability Index (MSI); meanwhile in Chlorophyll Stability Index (CSI) increased up to 20.4 percent. The proline content was decreased up to 26.9 percent by the application of nanosilica (400 ppm) in drought-stressed plants. Trichome length and the length of the silica bodies were significantly increased by about 17.4 and 9.1 percent over the control respectively. Application of 400 ppm nanosilica resulted in a maximum increase of 68.9 percent and 29.4 percent in terms of trichome and silicon bodies’ length over the drought treatment, respectively. Stomatal structures were reduced significantly with a mean reduction of 43.5 percent compared to the control in both the rice varieties. Application of 400 ppm nanosilica increased the mean stomatal size by 65.5 percent in drought stressed plants. Comparing the two varieties, CO54 expressed a greater response to 400 ppm of nanosilica treatments in terms of leaf area, specific leaf weight, Menbrane Stability Index (MSI), Chlorophyll Stability Index (CSI), proline and leaf surface characters under drought.