Grains and field crops
a) Effect of alfalfa mosaic virus infection on productivity of spaced plants.
Location: South Perth.
Spaced plant trials were done with AMV-EW isolate. Young plants of sub. clover cv. Daliak growing in jiffy pots were inoculated with AMV- containing sap or mock-inoculated with healthy sap and then transplanted onto the South Perth plots in paired rows separated by oat buffer rows.
b) Effect of Bean Yellow Mosaic Virus on productivity of grazed swards. (90MT14).
Location: Mt Barker.
A trial was done to examine the effect of BYMV infection on productivity of grazed subterranean clover swards.
c) Persistence of CMV from year to year in grazed swards (87BA24 and 87MT 50)
Location: Badgingarra and Mt Barker.
A five year trial was set up in 1987 at Badgingarra (87BA24) and Mt Barker (87MT50). In 1990, the plots grew well at both sites.
d) Occurrence of subterranean clover Mottle Virus in subterranean clover pastures.
Location: Albany, Bridgetown, Manjimup, Busselton, Bunbury, Harvey and Esperance.
A survey of old (> 5 years since reseeding) and new pastures in high rainfall zones (> 600 mm/year) was done in October 1990 to determine the incidence of BYMV.
e) Observations on SCMV distribution in infected pastures.
Location: Mt Barker
Pastures at Mt Barker Research Station were found to contain SCMV infected plants. These included cultivar mixtures in which cvs Woogenellup or Esperance were a component.
f) Reactions of resistant or partially resistant subterranean clover cultivars to SCMV infection.
From work by J. Wroth on the systemic reactions of cultivars of sub. clover to SCMV inoculation (see 1988 Experimental Summary), these were divided into resistant, partially-resistant and susceptible groups based on their tendency to develop systemic infection following sap inoculation. However, no information was available on the reactions of inoculated leaves to infection in the resistant and partially-resistant cultivars.
g) Concentration of SCMV in leaves of resistent sub. clover cultivars.
When inoculated leaves were picked from sap inoculated cv. Green Range (partially resistant cultivar) plants 5 weeks after inoculation (6 leaves/plant) and diluted 1/10, 1/100 and 1/1000, ELISA O.D. values were not decreased at all by dilution in any of them.
Number of Pages
Jones, R A. (1990), Virus diseases of subterranean clover.. Department of Agriculture and Food, Western Australia, Perth. Report.