Short Communication: First report of Nectria haematococca causing a moler disease on shallots in West Nusa Tenggara, Indonesia

Abstract

Moler disease caused by Nectria haematococca is the main disease of shallots in West Nusa Tenggara, Indonesia. Moler disease caused significant yield loss and even crop failure. The purpose of this study was to isolate and identify the pathogen causing moler disease on shallots. This research was conducted from February 2018 to November 2019. Survey was conducted at 13 shallot planting locations in West Nusa Tenggara, namely: Ngali, Ncera, Cenggu, Renda, Sajang, Rensing, Dasan Baru, Batu Layar, Anyar, Sembalun, Jerowaru, Batujai and Sakuru Village. Ten infected plants were taken, at each observation point, then put in a labeled plastic bag and brought to the laboratory for isolation purposes. The results showed that pathogen causing moler disease on shallot was isolated NTB2018. On PDA isolate NTB2018 produced white color colony, the mycelium growth direction was sideways with smooth mycelium structure, sideways growth direction of mycelium and fine structure mycelium. The fungus produced insulated mycelium consisting of macroconidia and microconidia as asexual spores and ascospores as sexual spores. Based on analysis of 18S rRNA gene, isolate NTB2018 DNA fragment of ±569 bp.