Characterization of Neopestalotiopsis sp. Causing Scab on Guava (Psidium guajava L. Cultivar Kristal) in Wonogiri Indonesia
Azizah Ridha Ulilalbab(a*), Miftahul Ajri(a), Danar Wicaksono(a), Mofit Eko Poerwanto(a), Aura Dhamira(b), Seto Agung Kuncoro(a)

a) Department of Agrotechnology, Faculty of Agriculture, Universitas Pembangunan Nasional Veteran Yogyakarta, Yogyakarta, Indonesia
*azizah.ridha[at]upnyk.ac.id
b) Department of Agribusiness, Faculty of Agriculture, Universitas Pembangunan Nasional Veteran Yogyakarta, Yogyakarta, Indonesia

Abstract

Crystal guava is one of the most popular fruit with high demand widely grown in the tropics area, especially in Indonesia. However it is affected by pathogen causing scab on guava fruit that could decrease product quality. This study aimed to identify the causal agent of scab on guava crystal fruit in Watulembu District, Wonogiri Indonesia. This method are isolation and identification of scab on guava pathogen through Koch^s Postulate application. The symptoms observed were brown lesions surrounded by dark brown borders, corky, scab on fruits matured. Based on morphological and molecular characterization showed that Neopestalotiopsis sp was causal agent of scab on guava. The morphological colony were shown with white blackish mycelium with granular and velvety colony texture included to fast group of mycelial growth rate. They had fusoid conidia with straight curved at ends. Pathogenicity test showed that incubation period of the fungal was 7 days after inoculation on fruits matured. The DNA amplification results was at 550 bp for Neopestalotiopsis.

Keywords: crystal guava- Neopestalotiopsis sp.- characterization- scab

Topic: Agriculture