Chlorophyll Stability and Photosynthesis Efficiency as Indicators of Drought-Tolerant Brown Rice Rice Selection

Abstract

Drought stress is one of the major limiting factors in rice production, particularly for red rice varieties that are commonly cultivated in dryland areas. Water deficiency leads to a reduction in chlorophyll content, disruptions in the photosynthetic system, and an increase in the formation of reactive oxygen species (ROS) that damage chloroplast structures. Drought-tolerant plants are able to maintain the stability of photosynthetic pigments through enhanced antioxidant activity, the accumulation of osmotic compounds, and improved water-use efficiency. This paper discusses the role of chlorophyll content and photosynthetic efficiency as key physiological indicators for assessing plant drought tolerance. Findings indicate that plants with higher chlorophyll content, stable chlorophyll fluorescence values (Fv/Fm), and good photosynthetic efficiency exhibit greater adaptive capacity under water deficit conditions. Therefore, these physiological parameters can be used as selection criteria in breeding programs for drought-tolerant red rice to support sustainable productivity in suboptimal lands.