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ARS Home » Southeast Area » Fort Pierce, Florida » U.S. Horticultural Research Laboratory » Subtropical Plant Pathology Research » Research » Publications at this Location » Publication #321071

Title: Efficiency of chemotherapy coupled with thermotherapy against citrus HLB

item ZHANG, MUQING - University Of Florida
item YANG, CHUANYU - University Of Florida
item Duan, Ping
item Shatters, Robert - Bob
item POWELL, CHARLES - University Of Florida

Submitted to: International Research Conference on Huanglongbing
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2014
Publication Date: 3/30/2015
Citation: Zhang, M., Yang, C., Duan, Y., Shatters, R.G., Powell, C. 2015. Efficiency of chemotherapy coupled with thermotherapy against citrus HLB. J Cit Pathol. 2(1):48. iocv_journalcitruspathology_30222.

Interpretive Summary:

Technical Abstract: Six independent experiments were carried out to evaluate the effectiveness of the chemotherapy coupled with the thermotherapy on pot-contained HLB-affected plants based on our previous results from graft-based methods. Three-year old potted HLB-affected citrus plants were exposed to 4 thermotherapy regimes in a CMP5000 growth chamber, with fluorescent lamps at 60% intensity, a 12-h photoperiod, and 50 % relative humidity, including i) 12-h @ 40 ºC/12-h @ 30 ºC for one week; ii) 12-h @ 42 ºC/12-h 30 @ ºC for one week; iii) 12-h 45 @ ºC/12-h 30 @ ºC for one week; iv) 12-h 45 @ ºC/12-h 30 @ ºC for shoot, but the root kept at constant temperature of 25 ºC for one week. After heat treatment, the plants were moved to the greenhouse for chemical treatments. Total 18 chemical treatments from 10 compounds or their combinations were applied at once every two weeks. Water was used as chemical control. Following treatments, all trees were tested for Ca. L. asiaticus using qPCR each every two months. The results indicated heat treatments promoted the growth of new flushes and leaves and eliminated the Las bacterium in the new leaves with increase of the treatment temperature. The chemical effectiveness against citrus HLB were subject to the tested compounds and their combinations. Some compound combinations (ACT+ZS and ACT+VA) effectively eliminated the Las bacterium, which resulted the recovered growth of the HLB-affected plants in greenhouse.