- Narrow distribution. Philippines (taro vein chlorosis), Oceania (taro vein chlorosis and Colocasia bobone disease). The viruses causing these diseases are:
- CBDV - infects all taro. Virus causes: i) dark green distorted patches in leaves that then recover, ii) alomae with other (unknown) viruses - plants (called ‘male’ taro in Solomon Islands) die. In a few alomae resistant varieties (called ‘female’ taro in Solomon Islands) CBDV causes bobone - stunted, thickened, green twisted leaves that eventually recover and appear healthy.
- TaVCV - infects all taro. Virus causes bright yellow, feather-like patterns, often above the veins at margins of leaves. The veins turn brown with age.
- Spread of CBDV by planthoppers; spread of TaVCV presumed to be planthoppers. TaVCV exists as at least two strains, Fiji and Vanuatu.
- Natural enemies: egg-sucking bug, Cyrtorhinus.
- Cultural control: remove plants with alomae as soon as seen (cover plant with e.g., rice bag, pull out capturing planthoppers) and burn; avoid growing varieties susceptible to alomae; grow ‘female’ taro if varieties available; avoid planting near plots with alomae.
- Chemical control: use synthetic pyrethroids against planthoppers, but they will likely kill natural enemies. Test Derris (fish poison).
Pacific Pests, Pathogens and Weeds - Online edition
Pacific Pests, Pathogens, Weeds & Pesticides
Taro rhabdovirus diseases (089)
Bobone and taro vein chlorosis.
Viruses assoicated with these two rhabdoviruses are: i) bobone = Colocasia bobone rhabdovirus (CBDV) and ii) taro vein chlorosis = Taro vein chlorosis virus (TaVCV). There is evidence that TaVCV in Fiji and Samoa are different strains.
AUTHORS Helen Tsatsia & Grahame Jackson
Information from Lethal taro viruses - still unresolved. (https://www2.pestnet.org/other-pacific-plant-protection-stories/); and Carmichael A, et al. (2008) TaroPest: an illustrated guide to pests and diseases of taro in the South Pacific. ACIAR Monograph No. 132, 76 pp. (https://lrd.spc.int/about-lrd/lrd-project-partners/taropest); and Revill RA, et al. 2005) Incidence and distribution of viruses of Taro (Colocasia esculenta) in Pacific island countries. Australasian Plant Pathology 34: 327-331; and Shaw DE, et al. (1979) Virus diseases of taro (Colocasia esculenta) and Xanthosoma sp. in Papua New Guinea. Papua New Guinea Agricultural Journal 30: 71–97; and from Macanawai AR, et al. (2005) Investigations into the seed and mealybug transmission of the Taro bacilliform virus. Australasian Plant Pathology 34: 73-76. Photo 6 Rothamsted Research, Harpenden, UK.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.