Main Article Content

Importance of the onion leaf twister disease in Ghana and the effect of Trichoderma asperellium on the mycelial growth and sporulation of the causal agent


N. Gyempeh
S.K. Offei
E.W. Cornelius
J.O. Honger

Abstract

Abstract
Studies were carried out to determine the disease incidence and severity of the onion leaf twister disease in the Eastern Region of Ghana to confirm the aetiology of the disease in the country. Field survey was carried out in two districts of the Eastern Region and the disease incidence and severity were measured. The causal agent was isolated on media and identified using morphological characteristics, and polymerase chain reaction with the species specific primer CgInt combined with ITS4 primer. The effect of Trichoderma asperellium on the mycelial growth and sporulation of the causal agent of the disease were determined. The results showed that the disease incidence was 43.6 per cent and 62.5 per cent in the Kwahu South and Fanteakwa districts, respectively, with severity of 0.8 and 2.7 respectively, on a scale of 1 – 5. The causal agent was confirmed as Colletotrichum gloeosporioides. The bio-agent, T. asperellium was able to significantly suppress the mycelial growth and sporulation of the pathogen infecting the onions.


Journal Identifiers


eISSN: 0855-1448
print ISSN: 0016-9544