Growth and development in plants are regulated through a cascade of signalling processes operating between source and sink via carbohydrate uptake, allocation and partitioning. Overall productivity in plants is regulated by the interplay between activity of source and sink strength, mediated through intricate signalling pathways. The importance of source - sink balance becomes particularly evident when either process is disrupted. Various factors, including phytohormones, nutrient availability and environmental conditions, modulate sink strength and source activity. Crop yield depends not only on photosynthetic capacity at the source but also on the efficient transport of assimilates and the ability of sink organs to utilize and store these resources. Although considerable research has focused on enhancing photosynthesis, comparatively less attention has been given to improving assimilate transport and sink strength. Therefore, integrating molecular approaches with physiological strategies to manipulate source-sink relationships offers significant potential for increasing crop productivity and yield.
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