Oxylipin levels during stolon to tuber transition in potato

CENZANO A, VIGLIOCCO A, ABDALA G.

Villa Carlos Paz, Córdoba

Congreso; XXXVIII Reunión Nacional Anual Sociedad Argentina de Investigación Bioquímica y Biología Molecular; 2002

Sociedad Argentina de Investigación Bioquímica y Biología Molecular.

Various substances related to jasmonic acid (JA) have been identified in potato plant leaves. However, there is no report about the isolation of the hydroxylated forms in stolons or tubers. We investigated the variations in endogenous jasmonates in the apical tips and stolons of Solanum tuberosum cv. Spunta, during the transition of stolons into tubers. Stolon with hooked apical tip, swelling stolon initiation, advanced swelling stolon and tuber were collected from plants of 8 weeks of age. The Asignatural was split in apical region and stolon. We identified JA, methyl jasmonate (Me-JA), 11-OH-JA and 12-OH-JA. The content of 12-OH-JA was higher than that of 11-OH-JA in the four stages, both in the apical tips and stolons. However, both compounds showed a different time-course in the apical tips, while 11-OH-JA increased, 12-OH-JA content decreased. The changes in JA and 12-OH-JA content during the transition of stolon into tuber were similar. The maintenance of a high level of both compounds in the stolons together with a decrease in the apical tips, suggests that the tips might be sites of metabolization and stolons could act as supplier pathways of JAs to the tips. Thus, JA from leaves or roots could be transported as 12-OH-JA to the apical tips, stimulating the tuber formation by cell expansion and vascular tissue differentiation. It is not yet known if there is a casual relation between presence of JA-hydroxylated forms and tuber formation; however, it is reasonable to assume that these compounds are also involved in storage organ formation.