Physiological and anatomical adaptations of rice (Oryza sativa L.) grown under drought stress

Abstract

Drought stress can affect significant productivity and quality attributes in rice. This research assessed the impact of drought stress on the physiological and anatomical adaptations of ‘Tubtim Chumphae’ rice. Seedlings were cultivated for 45 days in soil before being subjected to drought stress. The seedlings were divided into two groups as full water capacity treatment and drought stress treatment for 21 days before rewatering for 10 days. Dehydration from drought stress reduced rice seedling plant height, tiller number, leaf size, and fresh and dry weight while leaf rolling score increased. The recovery process from drought stress impacted the physiological characteristics. Relative water content and chlorophyll fluorescence decreased while green intensity (SPAD value), chlorophyll content, electrolyte leakage percentage, and malondialdehyde (MDA) content increased. Anatomical studies using free-hand section and peeling techniques revealed that water deficit reduced vascular bundle size, bulliform cell size, stomatal size, and epidermal cell (short cell) size while leaf thickness, cuticle and cell wall thickness and bulliform cell number increased. Our results provide useful information on rice seedling adaptation and response to drought for use in further studies of ‘Tubtim Chumphae’ rice and other cultivars.