ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Epidemiological aspects of citrus huanglongbing (greening) disease in Thailand.

Koizumi, M.; Prommintara, M.; Linwattana, G.; Kaisuwan, T.;

JARQ, Japan Agricultural Research Quarterly Year: 1997 Vol: 31 Issue: 3 Pages: 205-211 Ref: 8 ref.

1997

บทคัดย่อ

During 1992-93, citrus huanglongbing (HGB, greening) disease, caused by insect-borne Liberobacter, was investigated in the field in Thailand. The disease and its vector, Diaphorina citri, were present in all the citrus orchards surveyed in 12 districts. Electron microscopy confirmed the presence of Liberobacter in sieve cells of leaves with symptoms. Many viruliferous psyllids that transmitted the pathogen to young citrus seedlings were collected in HGB-infected fields. Although many orchards had been destroyed by the disease, some pummelo (Citrus maxima) orchards were still productive. HGB disease spread from infected trees to healthy C. maxima trees. Sour lime, C. aurantifolia, was the major HGB-carrier and inoculum source. Circulation of infected nurseries or bud-sticks through growers promoted inter-field transmission of the disease. The disease was more prevalent in flat or plain fields than in those surrounded by hills or wind breakers. Rough lemon, Calamondin, Som-pan and Ladu mandarins w

ere tolerant, while large numbers of sweet orange, mandarin and tangelo trees were susceptible. The tree growth and yields were markedly reduced by the disease when the trees were infected when young. Grapefruit, some tangelos and Som-pan mandarin trees were highly productive, while large numbers of mandarin and sweet orange trees showed low productivity.