RESEARCH PAPER Role of stressed mango host conditions in attraction of and colonization by the mango bark beetle Hypocryphalus mangiferae Stebbing (Coleoptera: Curculionidae: Scolytinae) and in the symptom development of quick decline of mango trees in Pakistan Asad MASOOD 1 , Shafqat SAEED 1 , Nadir ERBILGIN 2 and Yong JUNG KWON 3 1 University College of Agriculture, Bahauddin Zakariya University, Multan, Pakistan 2 Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada 3 School of Applied Biology and Chemistry, Kyungpook National University, Daegu, Korea Correspondence Shafqat Saeed, University College of Agriculture, Bahauddin Zakariya University, Multan 60000, Pakistan. Email: bumblebeepak@gmail.com Received 13 July 2010; accepted 31 August 2010. doi: 10.1111/j.1748-5967.2010.00304.x Abstract The mango sudden death syndrome has become a serious threat to the mango industry and caused significant decline in mango production worldwide. The bark beetle Hypocryphalus mangiferae (Stebbing) (Coleoptera: Curculionidae: Scoly- tinae) has been suggested as a potential vector of the disease based primarily on field observations with little or no supporting empirical data. In this study, we investigated the role of infected mango trees in host attraction and colonization by H. mangiferae to determine if beetle attack and colonization contributes to the disease progression on mango trees. Initially, the role of various stress factors on beetle attraction and disease progression was assessed under lathe house conditions from 2008 to 2009. Results suggest that symptomatic or recently inoculated mango trees (without any obvious symptoms) are preferentially colonized by H. mangiferae. Although not significant, high numbers of beetles attacked stressed or wounded mango trees, compared to healthy or dead mango trees. Disease symp- toms after beetle colonization, such as bark splitting, wilting and oozing, were further evaluated. These symptoms showed positive correlation with the degree of disease severity and host plant condition. Furthermore, two fungi, Ceratocystis fimbriata and Lasiodiplodia theobromae, were frequently isolated from the beetle and beetle-colonized trees. Based on these findings, they suggests that H. mangiferae can vector multiple fungi associated with mango sudden decline disease and play a significant role in outbreaks of this disease. Key words: bark beetle, disease-associated fungi, host preference, Hypocryphalus mangiferae, mango sudden decline disease. Introduction Introduced insect pests and diseases have affected a large number of native plant biota and caused significant eco- logical and economic effects worldwide (Vitousek et al. 1996). For example, the recent appearance of an exotic pathogen complex on mango trees Mangifera indica L. (Anacardiaceae) in Pakistan and Oman has become a serious threat to the mango industry and these pathogens have caused significant decline in mango production worldwide (Al-Subhi et al. 2006; Van Wyk et al. 2007). The origin of the pathogen complex is not known; however, it has been suggested that the pathogen complex might have been introduced via a planting stock into Oman from South America and then to Pakistan (Van Wyk et al. 2005, 2007). Entomological Research 40 (2010) 316–327 © 2010 The Authors Entomological Research © 2010 The Entomological Society of Korea and Blackwell Publishing Asia Pty Ltd