ilkari Conservation Group   est.1990     last update 13-8-3

 

GUIDELINES FOR FIELD RELEASES OF THE BRIDAL CREEPER RUST

USING WHOLE PLANTS:

 

(First attempted by Ilkari November 2000)

 

The bridal creeper rust fungus, Puccinia myrsiphylli, has been thoroughly

tested in CSIRO quarantine facilities in Canberra, has been scrutinised by

21 organisations nation wide and is proven to be safe for release in

Australia. It is absolutely specific to bridal creeper . This project was

funded by the CRC for Weed Management Systems, ANZECC and CSIRO Entomology.

 

contact    Rick Roush (08 8303 6590)  rick.roush@adelaide.edu.au

 

… Releases are most effective when made on a rainy/overcast day or at the

end of the day (4-5 pm) to avoid hot temperatures if site is exposed to

full sun. If the site is in the shade, releases could be made in the middle

of the day to take advantage of the warmer winter temperatures. Infection

of plants by the rust is optimum at cool temperatures (16-20oC) in a humid

environment for about 16 h.

 

… The infected plants in pots used for inoculation can be used to release

at other sites, or can be left in the field, as they will continue to

produce spores for a few weeks. We have had successful inoculations in

Adelaide just by leaving the potted plants entwined with uninfected plants

in the field. Please keep the potted plants from drying out. 

 

… Most efficient (but time consuming) inoculation of plants is performed by

'rubbing' the foliage of infected plants onto healthy foliage in the field.

This is achieved by sliding back and forth the infected foliage within the

foliage of plants in the field to dislodge spores from pustules and allow

their deposition on the under surface of leaves. It is important to realise

that the rust infects via stomata which are located on the under surface of

leaves and stems, so rubbing the underside of infected leaves onto the

underside of the uninfected leaves is likely to be most effective. 

… If it is not a rainy day, mist inoculated field plants with water and

cover the area with a sheet of clear plastic held in place with a few rocks

or pegs to provide a humid environment for 16-24 h or overnight. If the

site is in full sun, the plastic sheet should be removed the next morning

to prevent plants heating up.

Under optimum temperature (approx. 20oC), the first signs of infection on

plants appear as tiny yellow flecking at about 15 days after inoculation.

It is possible that in the field the first signs of infection will take

slightly longer to appear (up to 3-4 weeks).  These tiny flecks develop

into rust pustules in about 7-15 days.