RIYADH, 12 July — A highly destructive AIDS-like disease has struck citrus plantations in Najran in southwestern Saudi Arabia and greatly reduced their yield.
“It is very difficult to diagnose and detect this plant disease,” Dr. Hung-Ji Su, professor of plant pathology and entomology at National Taiwan University in Taipei, told Arab News. He said the only way to control the disease was the establishment of a pathogen-free nursery to breed a new generation of healthy plants.
Prof. Su said he donated diagnostic kit and disease-free saplings to the owner of a disease-stricken orchard. Dr. Eric C. Yang, head of the Republic of China’s Technical Mission in Saudi Arabia, and Younus Ma, press counselor at the Taipei Economic and Cultural Representative Office, were also present.
Prof. Su, who came to Saudi Arabia through the UN’s Food and Agricultural Organization and the ROC Technical Mission, spent four weeks in Najran. His mandate was to identify the greening fastidious bacterium (GFB) that pales the color of citrus fruits and leaves.
The project was undertaken under the overall supervision of the National Coordinator for International Agreement at the Ministry of Agriculture and Water, head of the ROC team in Riyadh and the national project director of Najran Horticulture Development Research Center.
The terms of reference were to undertake a survey of virus and virus-like diseases of citrus with special emphasis on greening and bacterial canker and other virus/virus-like diseases in Najran plantations.
Another objective of the survey was to review the existing infrastructure, equipment and material in the Plant Protection Unit and recommend additional equipment as required. Training of Saudi staff on the detection of virus and virus-like diseases by Elisa and PCR techniques were the other terms of reference. The Taiwanese expert trained 15 Saudis, 13 in Najran and two in Riyadh, to conduct the tests.
Prof. Su said he carried out his research in the plantation of Muhammad Al-Musallam. All the citrus plants affected by the disease lost their green pigmentation and did not yield.
He explained that citrus greening has seriously affected citrus trees in parts of Southeast Asia and Africa. “It causes great damage to the citrus industry by shortening the life span of trees. The greening disease is transmitted mainly through vegetative propagation.” However, Taiwan was making use of biotechnological research in the detection of the disease.
Referring to activities of the ROC Technical Mission here, Dr. Yang said it had been cooperating with the ministry in pest control, water resources management, saline water fish breeding, shrimping and tissue culture.
He said Chinese fishery experts working at the Jeddah Fish Farming had successfully bred 959,500 saltwater tilapia fry.
