Tree dieback in Punjab, Pakistan.
Arshad Javaid, Rukhsana Bajwa, Tehmina Anjum
Author Affiliation: Department of Mycology and Plant Pathology, University of the Punjab, Lahore 54590, Pakistan.
Mycopath 2 : 1-5
Abstract : Survey of 10 districts of Punjab, namely Sialkot, Gujranwala, Lahore, Faisalabad, Sheikhupura, Gujrat, Jehlem, Rawalpindi, Sargodha and Hafizabad, were undertaken from March 2003 to March 2004 to study the present status of tree dieback incidence in these areas. A total of 21 tree species were infected with the dieback disease. The disease incidence, however, varied in different tree species. Furthermore, there was also difference in disease severity in different surveyed districts of the province. Dalbergia sissoo and Acacia nilotica were the most affected species in all the districts. Among the commonly grown trees, Mangifera indica, Eucalyptus citriodora, E. camaldulensis, Populus hybrida, Ficus religiosa, F. benghalensis, Bombax ceiba, Syzygium cumini, Psidium guajava and Albizia lebbeck were found affected with dieback. The less commonly cultivated species like Toona ciliata, Heterophragma adenophyllum [Haplophragma adenophyllum], Ficus glomerata [F. racemosa], Mimusops elengi, Terminalia arjuna, Grevillea robusta, Ehretia acuminata, Platanus orientalis and Barringtonia acutangula were also found victims of the dieback. Termites and fungi, especially Phytophthora sp., were the most common biotic factors responsible for the disease. Among the abiotic factors, generally drought and environmental pollution seemed to be the main causes for dieback initiation and severity.