Physiological mechanisms associated with the development of internal necrotic disorders of potato

Physiological disorders such as Brown Center and Internal Brown Spot affect the quality of potato tubers destined for fresh and processing markets. Cultural and environmental factors giving rise to such disorders have been studied extensively. Considerably less information is available on the underpinning physiological, molecular and biochemical mechanisms. However, the cell's calcium status clearly plays an important role in resistance responses. Whilst extreme genotypic susceptibility to these disorders exist such variation has not been exploited fully to dissect the genetics and biochemistry of the key processes. This is central to the selection of resistant germplasm or to the manipulation of existing genotypes for improved tolerance.