Calcium Route in the Plant and Blossom-End Rot Incidence

Calcium (Ca2+) is a macro-mineral essential for the growth, development, yield, and quality of vegetables and fruits. It performs structural, enzymatic, and signaling functions in plants. This review outlines Ca2+ translocation from soil to fruit via the plant xylem network, emphasizing the importance of Ca2+ compartmentalization within fruit cell organelles in developing the Ca2+-deficiency disorder, blossom-end rot (BER). The causes and possible control measures of BER are also discussed. Soil available Ca2+ enters the root apoplast with the water flow and moves towards the xylem via apoplastic or symplastic routes. The transpiration force and growth of organs determine the movement of Ca2+-containing xylem sap to aerial plant parts, including fruits. The final step of fruit-Ca2+ regulation is the partitioning among cellular compartments, which determines susceptibility to Ca2+-deficiency disorders such as BER. Depleting cytosolic and apoplastic Ca2+ due to excessive deposition in organelles such as the vacuole may lead to disintegration of the plasma membrane, resulting in BER, even at high Ca2+ availability at the blossom end of the fruit. BER management requires cultural and physiological practices that ensure Ca2+ translocation to the fruit and proper Ca2+ compartmentalization. The use of BER-resistant and Ca2+-efficient cultivars may also help in BER management. Therefore, a comprehensive understanding of Ca2+ dynamics in plants is crucial for managing BER, reducing production costs, minimizing environmental impact, and enhancing crop productivity.