Physiological disorders in tomato and some methods to avoid them

Tomato can be injured by two very important physiological disorders, namely blossom end rot (BER) and fruit cracking (FC). The purpose of this review is to describe these physiological disorders and to assess whether cultivar and cropping system can minimise their symptoms. Physiological Ca deficiency is usually related to the inability of the plant to translocate adequate Ca to the affected plant part, rather than to insufficient Ca levels in the growing medium. The first visible symptom of BER is a small darkened or water-soaked area around the blossom end of the fruit, appearing about the time the fruit begins to ripen. The spot darkens, enlarges, and becomes sunken as the fruit matures. Large lesions may show in concentric rings. FC is the splitting of the epidermis around the calyx or stem scar. FC is a physiological disorder, which mainly occurs when there is a rapid net influx of solutes and especially water into the fruit, while at the same time ripening or other factors reduce the strength and elasticity of the tomato skin. This review article gives an overview of the causes of BER and FC and summarizes growing methods aimed at reducing these physiological disorders of tomatoes.