Phytohormone-Mediated Regulation of Sprouting in Tuber and Storage Root Crops

Abstract

AbstractTuber and storage root crops are staple food in several tropical countries. Potato and yam are the two widely cultivated tuber crops, and sweet potato is the most important storage root crop after cassava. The belowground storage organs of these crops are delicious, nutritionally rich and have medicinal applications. Potato and yam tubers as well as sweet potato storage roots have unique abilities to sprout under favorable conditions to form new plants. However, the short dormancy period of these storage organs, especially sweet potato, causes significant losses in the quality for human consumption, and is a major limitation for their global cultivation. The sprouting phenomenon is widely studied in potato, and numerous genes related to metabolism, transport and signaling pathways of phytohormones and sugars are identified that could act as crucial regulators of the sprouting process. However, the literature is scarce regarding sprouting of yam tubers and sweet potato storage roots. Despite the enormous importance of the tuber and storage root crops, knowledge about the molecular mechanism governing the sprouting process is limited. In this chapter, the roles of various molecular factors, phytohormones and their signaling crosstalk are discussed during the sprouting of tubers in potato and yam, and sweet potato storage roots.KeywordsPhytohormonesPotatoSproutingSweet potatoStorage rootYam