Login | Create Account (DAF staff only)

Dynamics of plant populations in Heteropogon contortus(black speargrass) pastures on a granite landscape in southern Queensland. 2. Seed production and soil seed banks of H. contortus

Orr, D.M. and Paton, C.J. and Playford, C. (2004) Dynamics of plant populations in Heteropogon contortus(black speargrass) pastures on a granite landscape in southern Queensland. 2. Seed production and soil seed banks of H. contortus. Tropical Grasslands, 38 . pp. 31-41.

Full text not currently attached. Access may be available via the Publisher's website or OpenAccess link.

Publisher URL: http://www.tropicalgrasslands.asn.au

Abstract

Seed production and soil seed hanks of H. contortus were studied in a subset of treatments within an extensive grazing study conducted in H. contortus pasture in southern Queensland between 1990 and 1996.

Seed production of H. contortus in autumn ranged from 260 to 1800 seeds/m2 with much of this variation due to differences in rainfall between years. Seed production was generally higher in the silver-leaved ironbark than in the narrow-leaved ironbark land class and was also influenced by a consistent stocking rate x pasture type interaction.

Inflorescence density was the main factor contributing to the variable seed production and was related to the rainfall received during February. The number of seeds per inflorescence was unaffected by seasonal rainfall, landscape position, stocking rate or legume oversowing. Seed viability was related to the rainfall received during March.

Soil seed banks in spring varied from 130 to 520 seeds/m2 between 1990 and 1995 with generally more seed present in the silver-leaved ironbark than in the narrow-leaved ironbark land class. There were poor relationships between viable seed production and the size of the soil seed bank, and between the size of the soil seed bank and seedling recruitment.

This study indicates that H. contortus has the potential to produce relatively large amounts of seed and showed that the seasonal pattern of rainfall plays a major role in achieving this potential

Item Type:Article
Corporate Creators:Department of Employment, Economic Development and Innovation (DEEDI), Agri-Science, Crop and Food Science
Business groups:Agri-Science, Crop and Food Science
Additional Information:© The Tropical Grassland Society of Australia Inc. Access to published version may be available via Publisher’s website.
Keywords:Heteropogon contortus; black speargrass; grazing; seed viability; inflorescence.
Subjects:Plant culture > Seeds. Seed technology
Animal culture > Rangelands. Range management. Grazing
Deposited On:28 Jun 2004
Last Modified:25 Oct 2011 23:18

Repository Staff Only: item control page