Characterisation of a carlavirus of French bean (VG15073)
What’s it all about?
This investment is characterising a new carlavirus found infecting Fabaceae crops in South East Queensland, and is set to identify potential distribution and incidence of the virus in other French bean production regions of Australia. Importantly, the project will develop and help growers adopt management strategies for the virus, resulting in improved pack-out, increased marketable yield and a reduction in the impact of the disease.
The project team has discovered that a disease in Queensland French bean crops in 2016 was caused by an infection of a Carlavirus in the Cowpea mild mottle group (CPMMV). This was the first record of this virus group from legumes in Australia.
Surveys of other French bean crops have been carried out, and CPMMV was found in several perennial legume species, including Siratro, in the Fassifern and elsewhere. They concluded that the virus is well established at several locations.
The effects of CPMMV were tested in 18 bean varieties in two field trials, which revealed that varieties currently used for commercial green bean production are highly susceptible to the disease.
The team identified several varieties that seem to have some resistance to CPMMV, and these will be tested further. They hope to find varieties that can be planted in locations where CPMMV is prevalent.
Research was carried out to find out how the disease is transmitted. Although work overseas has found CPMMV to be seed transmitted in several host species, the team has not been able to demonstrate seed transmission in their trials with beans and soybean. It seems likely that silver leaf whitefly might be transmitting the virus.
The team is also sequencing the virus to provide a greater understanding of the disease, which is known to affect mainly legumes including beans, soybeans, mung beans, cowpea, adzuki beans, siratro, and phasey bean.
This project is a strategic levy investment in the Hort Innovation Vegetable Fund