Separation of a Mycoplasmalike Organism from the Likubin Complex in Citrus. Chiou- Hsiung Huang, Plant Pathologist, Department of Plant Pathology, Taiwan Agricultural Research Institute, Wufeng, Taichung, Taiwan. Moj-Jih Chen, Professor of Plant Pathology, National Chung-hsing University, Taichung; and Ren-Jong Chiu, Senior Specialist, Joint Commission on Rural Reconstruction, Taipei, Taiwan. Plant Dis. 64:564-566. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-564.

Likubin mycoplasmalike organisms (MLOs) were separated from the likubin causal complex by using trifoliate orange seedlings to filter out tristeza virus. When Ponkan budsticks carrying the likubin MLO were grafted onto lime rootstocks, characteristic symptoms of likubin developed in 3–4 mo. The trees did not carry tristeza, according to the Mexican lime index test. Leaves from diseased plants contained MLOs in sieve tubes but not tristeza virus. Likubin MLOs and the likubin causal complex induced similar symptoms in tristeza-tolerant scion-stock combination citrus plants but dissimilar symptoms in tristeza-susceptible plants. Presence of tristeza virus seemed to suppress the yellowing symptom of MLOs, but the disease was more severe in plants infected with the causal complex than in plants infected with likubin MLO alone.