Research at UAF - Management of citrus leaf miner (Phyllocnistis citrella Stainton) to suppress citrus canker
Name of Principal Investigator: Dr. Sohail Ahmed
Phone: 041-9200161-169 (2903)
Fax: 041-9201083
Name of Co-Principal Investigator: Dr. Shahbaz Talib Sahi
Phone: 041-9200161-169
Fax: 041-9201083
Duration: 36 months
Cost: Rs. 1.555,709 millions
Funding agency HEC

Progress Reports

The project addresses the importance of leaf miner in nursery and groves.  A relationship between lea miner and citrus canker is being studied leading to management of leaf miner to reduce citrus canker.
Problem statement:
The occurrence of canker lesions on leaves with leaf miner damage is often noticed. The nature of relationship is yet to be shown in Pakistan. In plants where canker is severe, heavy defoliation will occur if the leaf-miner infestation is strong. Current research efforts are directed at finding the best treatment combination for both problems.
The integrated management of citrus leaf miner will help to reduce the incidence of citrus canker and to promote the export quality of citrus fruits from the areas where CLM is a danger to citrus production.

Ecology of CLM: Field biology, populations’ pattern, habitat preference. Performance of CLM in relation to citrus cultivars. Characterization of distribution of citrus canker and leaf miners; Correlation of climatic variables (temperature, rainfall, wind, relative humidity, and foliar wetting) with diseases progress, host growth (age of leaf) and leaf miner activities; Comparison of the effects of artificially produced lesions and lesions produced by Phyllocnistis citrella in the monocycle components of citrus canker; Assessment of bio-pesticides such as microbials, oils, and others (azadiractin etc.); Monitoring and assessment of indigenous natural enemies of CLM; Rearing of natural enemies and impact of CLM population regulation; Susceptibility of natural enemies to pesticides used in CLM control; Action threshold; Bio control of citrus canker and effect on citrus leaf miner; Integration of control measures for CLM and its impact on citrus canker.
Results                                   -
The year 2009 was unusual as there was unprecedented low rainfall and temperature was high so the changes in population of CLM are have not matched with previously recorded in the reports of Directorate of Pest Warning and Quality Control of Pesticides, Sargodha, however, temperatures plays an important role in producing peak of activity of CLM along with relative humidity. Rainfall may be important for spreading of canker. Plant contents are influenced by environments and affect CLM Infestation. The relationship between TPC and CLM infestation in Kinnow was significant, therefore, can be important factors in regulation of population. Citrus canker was severe on Kinnow and was associated with CLM galleries on this host plant. Lime had the same in month of August only. Weeds removal exposes soil to sunlight that may have increased temperature of environment that has affected development of leaf miner adversely. Leaf miner kept at high than 35°C died before reaching to margin of leaves. Weeds removal may have affected resting places for adults of leaf miner. Data are being taken to sweep nets on weeds to find adults on them. The application of botanical and microbes has not affected the leaf miner infestation in plants of citrus nursery and groves.