Phenology, Reproductive-Biology and Seed Development in Four Rush and Sedge Species From Western Australia

Abstract

Four species of Restionaceae and Cyperaceae from the Mediterranean-type climate region of Western Australia were studied to determine factor(s) limiting their reproductive performance. Ecdeiocolea monostachya (Ecdeiocoleaceae), Lepidobolus chaetocephalus (Restionaceae), Restio aff. sphacelatus (Restionaceae) and Mesomelaena pseudostygia (Cyperaceae) differed in the pattern of dry matter partitioning and phenological patterns. All species were moderately efficient at remobilising dry matter from senescing vegetative organs, maintaining constant tissue water to dry matter content in mature organs over the study period regardless of soil moisture availability. In situ nutrient and water supplements of study species did not elicit improved seed production or significant increases in dry matter accumulation (except for current and old culms of E. monostachya and spikelets of L. chaetocephalus). For all study species except L. chaetocephalus, seed production was low, while herbivore activity, insect predation andlor infection by a smut (Tolyposporium lepidiboli) reduced seed production potential in L. chaetocephalus and E. monostachya. Attempts at seed germination for all study species were not successful. Extracted embryos from mature seed of all species cultured in vitro grew rapidly, providing a reliable method for propagation of study species.