The first record of a serotype IV tospovirus in Australia

A serotype IV tospovirus was identified from capsicum, tomato and chilli plants in south-east Queensland. This is the first record of a serotype other than serotype I (Tomato spotted wilt virus) from Australia

Detection of Peanut stripe virus in post-entry quarantine in Queensland

Peanut stripe virus was detected by electron microscopy and serology in peanut plants growing in post-entry quarantine from seed imported from the USA. The virus was detected in 3.8% of plants and these had mottling on new growth leaves. The plants were destroyed

Sequence diversity in the coat protein coding region of the genome RNA of Johnsongrass mosaic virus in Australia

Sequence diversity in the coat protein coding region of Australian strains of Johnsongrass mosaic virus (JGMV) was investigated. Field isolates were sampled during a seven year period from Johnsongrass, sorghum and corn across the northern grain growing region. The 23 isolates were found to have greater than 94% nucleotide and amino acid sequence identity. The Australian isolates and two strains from the U.S.A. had about 90% nucleotide sequence identity and were between 19 and 30% different in the N-terminus of the coat protein. Two amino acid residues were found in the core region of the coat protein in isolates obtained from sorghum having the Krish gene for JGMV resistance that differed from those found in isolates from other hosts which did not have this single dominant resistance gene. These amino acid changes may have been responsible for overcoming the resistance conferred by the Krish gene for JGMV resistance in sorghum. The identification of these variable regions was essential for the development of durable pathogen-derived resistance to JGMV in sorghum