International Journal of Environmental & Agriculture Research (IJOEAR) ISSN:[2454-1850] [Vol-4, Issue-1, January- 2018] Page | 65 Characterization of antifungal activity of endophytic Penicillium oxalicum T 3.3 for anthracnose biocontrol in dragon fruit (Hylocereus sp) Suhaila Mamat 1 , Umi Kalsom Md Shah 2 , Nurul Atika Mohamad Remli 3 , Khozirah Shaari 4 , Rozeita Laboh 5 , Nor Aini Abdul Rahman 6 1,2,3,6 Department of Bioprocess Technology, Faculty Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia Email: umikalsom@upm.edu.my 4 Faculty of Sciences, Universiti Putra Malaysia 5 Department of Horticulture, Malaysia Agriculture Research and Development Institute, 43400 Serdang, Selangor, Malaysia Abstract— A group of 126 endophytic fungi was isolated from dragon fruit plants in Malaysia. Dual culture and disc diffusion test revealed that seven strains could suppress the growth of Colletotrichum gloeosporioides. Of all the potential strains, strain T3.3 exhibited the best antagonistic activity by producing an inhibition zone of 12±1.0 mm in dual culture test. Disc diffusion test using crude extract produced by this fungus could inhibit the growth of C.gloeosporioides by 33.33±2.89%. The diffused non volatile metabolite produced by this strain suppressed the growth of the pathogen by 97% after 7 days of incubation. Based on morphological characteristics and ITS region sequence, strain T3.3 was identified as Penicillium oxalicum. The carbon utilization profile in Biolog FF Microplate analysis revealed that P.oxalicum T3.3 is a versatile microorganism. P.oxalicum T3.3 was found to produce β-glucanase and chitinase with activity of 3.38 U/mL and 1.19 U/mL respectively. In addition, the ethylacetate extract of P.oxalicum T3.3 could suppress the growth of C.gloeosporioides. Scanning electron microscopy study showed that the release of extracellular antifungal metabolites from the endophytic P.oxalicum T3.3 had caused abnormal hyphal growth of C.gloeosporioides. Treatment with the crude extract from this fungus on dragon fruit could control anthracnose disease in this fruit in vivo. Thus, endophytic Penicillium oxalicum T3.3 is considered as a potential biological control agent of anthracnose disease in dragon fruit. Keywords— Antifungal, dragon fruit, endophytic fungi, Penicilium oxalicum. I. INTRODUCTION Colletotrichum.gloeosporioides is the causal agent of anthracnose disease and an important cosmopolitan fungal pathogen that infects many plant species worldwide (Cannon et al., 2012). This pathogen is present in various regions of the world including tropical to subtropical areas and can be destructive if left uncontrolled. In recent years, the occurrence of anthracnose disease in dragon fruit plant has affected fruit yield tremendously. (Masyahit et al., 2009). The disease occurs when the weather conditions, such as warm weather and frequent rains as well as inoculum were present. The common symptoms that usually observed in infected plants and fruits are sunken necrotic tissues with concentric rings where ascervuli emerge from it. The infected spot will coalesced to rot (Palmateer and Ploetz, 2006). This disease is controlled by a combination of cultural management practices and chemical control. The infected plant parts are pruned out and destroyed by burning them. Fungicides such as Benex, Arimo 23, Maneb and Mancozeb were applied to the farm to eradicate the fungal infection. However, the usage of chemical fungicide in the dragon fruit farm gives detrimental effect to the lives of human and had polluted the environment (Crissman et al., 1994). Apart from that, the development of fungicide resistance pathogen had complicated the disease management (Pimenta et al., 2010). Under such circumstances, there is a need to search for another alternative control method that is considered safe for human health and the environment. Currently, there is growing interest in using endophytic fungi as biological control agent (BCA). The use of endophytic fungi which reside asymptomatically inside host plant without causing any apparent disease as BCA is beneficial as they occupy the same ecological niche as the pathogens and may induce the defense responses of the hosts against the pathogens (Brum et al., 2012). Endophytic fungi also produce an array of secondary metabolites which may be exploited for use in agriculture and industry (Zhang et al., 2006). Many species of endophytic fungi mostly those belonging to the genus Penicillium are identified as biocontrol agents with antifungal activities against a number of plant pathogenic fungi (Xu et al., 2010; Elsharkawy, 2012; Murali, 2012). Penicillium sp. has also been reported to produce lytic enzymes including chitinase and β-glucanase which are involved in