Research

Our research aims to increase our understanding of the biology and ecology of the branched broomrape infestation in South Australia.  We have been able to assess the potential impacts of the weed by identifying host plants that can be parasitised by the strain of broomrape present in South Australia. Our applied research focuses on the development of effective, scientifically sound control strategies that are based on a thorough understanding of the broomrape life cycle. Our research results directly inform management decisions and program protocols.

Literature Review

Broomrapes are an important economic weed throughout the world and this literature review PDF (168.0 KB) provides a summary of the international research.

Potential hosts of branched broomrape

Branched broomrape has a large host range, although hosts are confined to broad-leaf plants. Our host testing PDF (1.4 MB) has defined hosts in broad-acre crops, vegetables, weeds, ornamental plants and native species.

Host list October 2009

Dispersal

Branched broomrape seeds are dust-sized and are dispersed by wind, water, livestock and other animals, and as contaminants of soil, fodder or seed. Our “traceback” project PDF (192.4 KB) identified potential vectors for broomrape spread so we could target areas for searches for new infestations. Farm machinery that has direct engagement with the soil or for harvesting of hay or cereal seed were the most frequently identified vectors.

Survey

The annual discovery survey provides data for evaluating the success of the eradication program. It is also a rich data source that is used for risk assessment purposes and defining the boundaries of the containment area.

Sampling for detection of branched broomrape PDF (1.8 MB)

Control options

Branched broomrape has a long-lived soil seed bank and must re-establish from seed each year.  Our research focuses on evaluating control options for directly destroying the soil seed bank or preventing the addition of seeds to the seed bank by killing broomrape before it emerges and fruits.

Sampling challenges in detecting branched broomrape seed bank decline PDF (135.2 KB)

Potential use of isothiocyanates in branched broomrape eradication PDF (152.6 KB)

Understanding the behaviour of dazomet in dryland farming soils PDF(1.8 MB)

Native vegetation monitoring

A low rate of Ally herbicide is aerially sprayed over native vegetation to control broomrape. We have been monitoring the effects of the herbicide spraying on several native perennial species and plots of annual plants.

Aerial spraying of herbicide in native vegetation