Pakistan J. Zool., vol. 44(1), pp. 101-108, 2012. In Search of the Best Hot Water Treatments for Sindhri and Chaunsa Variety of Mango Muhammad Faheem, 1 Shafqat Saeed, 1 Asif Sajjad, 1 Abdul Rehman 2 and Muhammad Farooq 3 1 Department of Plant Protection, University College of Agriculture, Bahauddin Zakariya University, Multan 2 CABI South Asia, Rawalpindi, Pakistan 3 Directorate of Quality Enhancement, Bahauddin Zakariya University Multan, Pakistan Abstract.- Pakistan produces world’s best quality mangoes and its growers and entrepreneurs would like to exploit new markets. Although hot water treatments of exportable mangoes effectively kill the fruit flies but can significantly deteriorate the fruit quality during post-storage period. In the present study, we tested the mango varieties Sindhri and Chaunsa on recommended i.e. 48°C for 60 minutes and two proposed hot water treatments i.e. 46°C for 60 minutes and 50°C for 60 minutes. All the three hot water treatments killed all the fruit fly eggs and larvae in both varieties of mango. Yet the fruit quality was affected during post-storage period of 9 days in terms of weight loss in Sindhri while stem end rot or brown rot and physical injury in Chaunsa. Based on the findings of current study, we recommend hot water treatment of Sindhri at 50 o C for 60 minutes and Chaunsa at 48 o C for 60 minutes. Key words: Hot water treatment, mango, Sindhri, Chaunsa, post storage quality. INTRODUCTION Mango ranks second in cultivated area and production among the fruits of Pakistan which is the fifth largest mango producer in the world (FAO, 2006). The bulk production of good quality mangoes is usually undermined by certain pre- harvest factors, like insect pests and diseases (Ishaq et al., 2004; Iqbal et al., 2004). Among insect pests, fruit flies are of great economic importance since they bring about huge loss through direct fruit damage and fruit drop (Ghafoor et al., 2010). Two of the fruit fly species attacking mangoes in Pakistan are known as oriental fruit fly, Bactrocera dorsalis and peach fruit fly B. zonota (Stonehouse et al., 2002). These two species are hindering the export of mangoes due to impaired quality and quantity (Stonehouse et al., 1998). Annual losses of fruits and vegetables in Pakistan caused by fruit flies are reported to be more than 144.6 million US dollars (Stonehouse et al., 2002). The emanating idea of improved quality and increased quantity of exportable mango through on- farm integrated management of orchards is quite young in Pakistan. Additionally the postharvest ___________________________ * Corresponding author: bumblebeepak@gmail.com 0030-9923/2012/0001-0101 $ 8.00/0 Copyright 2012 Zoological Society of Pakistan. technology lacks on commercial scale. Nevertheless, the importer countries necessitate some post harvest treatments like hot water, vapor heat and irradiation treatments, which ensure complete disinfestation of fruit flies (GuangQin et al., 1999; Corcoran et al., 2002; Collin et al., 2007). As a disinfestation treatment, hot water has earned fame and adoption at a large scale because of its high efficacy in reducing the post -harvest diseases (e.g. anthracnose and stem end rot) as well as its low cost (Jacobi et al., 1995; Esguerra et al., 2004; Sopee and Sangchote, 2005). For example, hot water immersion of mangoes at 45.9°C and 46.3°C for 39.7 and 68.5 minutes, respectively can induce 99.99 percent egg and larval mortality in South American fruit fly Anastrepha fraterculus (Nascimento, 1992). In 2005, Pakistan signed a protocol with Iran and China regarding export of mangoes which necessitates hot water treatment i.e. Iran: 45°C for 75 minutes; China: 48°C for 60 minutes (Anonymous, 2005b), but the consequences of such treatments on different mango varieties regarding fruit fly disinfestations, post-harvest diseases, shelf life and quality traits (Anwar and Malik, 2007) are yet to be tested. Heat involves both insecticidal and fungicidal action, but the treatment conditions optimized for insect control may not be optimal for disease control and, in some cases may even be detrimental for fruit (Coates and Johson, 1993). So