PHOTOSYNTHESIS EFFICIENCY AND GENETIC AND ENVIRONMENTAL INFLUENCES ON PLANT GROWTH

Photosynthetic efficiency is a fundamental determinant of plant growth, biomass accumulation, crop productivity, and terrestrial ecosystem functioning. As the primary biological mechanism through which solar energy is converted into chemical energy, photosynthesis regulates carbon assimilation and provides the metabolic foundation for plant growth and development. However, photosynthetic performance is not governed by a single physiological process; rather, it emerges from the complex interactions among genetic architecture, biochemical regulation, plant physiological characteristics, and environmental conditions. This paper examines the genetic and environmental determinants of photosynthetic efficiency, emphasizing their individual and interactive effects on plant growth, resource-use efficiency, and adaptive capacity under changing environmental conditions.At the genetic level, variation in genes regulating chlorophyll biosynthesis, photosystem assembly, electron transport, stomatal conductance, and carbon fixation contributes to differences in photosynthetic capacity among plant species and genotypes. The activity and regulation of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), together with the efficiency of photosystem I and photosystem II, influence the conversion of absorbed light energy into assimilated carbon. Genetic variation in these processes can consequently affect leaf-level carbon assimilation, intrinsic water-use efficiency, and biomass production. Environmental factors, including photosynthetically active radiation, temperature, atmospheric carbon dioxide concentration, water availability, soil nutrient status, and salinity, further regulate photosynthetic performance by modifying stomatal behaviour, enzymatic activity, photochemical efficiency, and carbon metabolism. Suboptimal conditions may induce photoinhibition, oxidative stress, and metabolic limitations, thereby reducing carbon assimilation and restricting plant growth.Importantly, genetic and environmental influences operate through interconnected physiological and molecular pathways, resulting in genotype-specific responses to environmental variability. Understanding these interactions is therefore essential for identifying traits associated with photosynthetic resilience and for developing crop improvement strategies suited to diverse agroclimatic conditions. Integrating molecular breeding, functional genomics, advanced phenotyping, remote sensing, and precision crop management can facilitate the identification and optimization of photosynthetic traits while accounting for resource limitations and environmental stress. Overall, this paper highlights the importance of a multidisciplinary approach to understanding photosynthetic regulation and its implications for plant productivity. Improved knowledge of genotype–environment interactions can support the development of climate-resilient crop varieties, enhance resource-use efficiency, and contribute to sustainable agricultural intensification and long-term food security under global environmental change.