Hypovirulent Microbes: Prospective Controllers of Banana Wilt

Hypovirulent Microbes: Prospective Controllers of Banana Wilt        

By: I Ketut Suada

             Barriers to banana cultivation are the attacks of Fusarium oxysporum f.sp. cubense (Focub) causes fusarium wilt. All existing banana cultivars are not resistant to this wilting disease. This change in resistant is due to the formation of a new strain (Fusarium strain-4) that breaks the resistance of all banana cultivars (Ploetz, 2015; Widinugraheni, 2018).

         Environmentally friendly control with Trichoderma spp. and Pseudomonas fluorescens are ineffective because the pathogen is already at the site of the attack, the plant xylem vessels. Biological agents that can be present at the site of the attack are very prospective to be a pathogen control agent. Such microbes are hypovirulent microbes obtained from the mutated pathogen. So, if the hypovirulent is applied to the original niche, then the hypovirulent will defeat the pathogen through competition for space, food, and even antibiosis (Ghoul and Mitri, 2016; Greulich et al., 2012). For this reason, pathogenic mutations to obtain hypovirulent are very important to do because the mechanism of inhibition is very promising, namely competition by replacing pathogens (Lloyd and Allen, 2015; Venegas-Ortiz et al., 2014).        Various mutation studies have been successful for various purposes. For example: mutations to oyster mushrooms (Pleurotus spp.), resulted mutants with better nutritional content than the original one (Djajanegara et al., 2007); the mutation of Trichoderma harzianum to increase its antagonistic power against Rhizoctonia solani, found 3 mutants (Abbasi et al., 2016); Grant et al., 2014), mutations to increase secondary metabolites from Penicillium have been successful (Iftikar et al., 2010). Meanwhile the mutation of Fusarium oxysporum f.sp. cubense for the manufacture of hypovirulent to control the pathogenic F. oxysporum f.sp. cubense wilt of banana fusariums has not been done.