SEEDLING GROWTH AND STORAGE CHARACTERISTICS OF SEEDER AND RESPROUTER SPECIES OF MEDITERRANEAN-TYPE ECOSYSTEMS OF SW AUSTRALIA

Juvenile (2-4 years old) plants of a taxonomically diverse range of dicotyledonous species were examined following recruitment from seed in recently burnt habitats in S.W. Australia. Obligate seeder species (those succumbing to fire) had on average, an almost threefold greater total plant d. wt and more than a fourfold greater shoot: root d. wt ratio than comparably-aged, cohabiting, resprouter species (those capable of surviving fire). Starch was generally much more concentrated in root dry matter of resprouters than seeders, and both categories exhibited greater starch storage capacity in roots than shoots. Members of the Myrtaccae were exceptional in not showing a greater root starch reserve in resprouter than in seeder species. and in carrying as high, or higher, starch levels in shoots as in roots. Anatomical investigations on roots provided instances of zero starch storage, storage, only in rays or in cortex, in rays and in xylem parenchyma, in rays and in cortex, or in all three locations. High starch ratings of resprouter roots related mostly to higher starch grain packing density at storage sites, but in certain instances these also reflected proportionally greater areas of tissue specifically devoted to storage. Dry matter of shoots of both seeders and resprouters generally contained higher levels of N, P, K, Ca and Mg than that of roots, but there was no significant evidence of elements being more concentrated in resprouters than in seeders. © 1990 Annals of Botany Company.