Post-harvest Survey of Fungal Diseases Associated with Soursop (Annona muricata L.) Fruits

Annona muricata L. (soursop) fruit, consumed globally, is highly susceptible to attack by fungal organisms. Fungal fruit rots' impact on Annona muricata is gradually increasing globally, with distribution in tropical areas, including southern Nigeria, resulting in reducing market availability and fruit quality. This study was aimed at surveying the post-harvest disease symptoms associated with Annona muricata fruits displayed for sales and the disease incidence-severity, which indicates the extent of the damage caused by the symptoms. Soursop fruit samples in Port Harcourt Local Government Area (PHALGA) and Obio-Apkor Local Government Area in Rivers State, Nigeria, were surveyed. Each fruit was scored on a disease severity scale of 0–4 (0% no disease), (1–25% trace of disease), (25–50% light disease), (50–75% moderate disease) and (75–100% severe disease). The data obtained were subjected to Analysis of Variance (ANOVA) and Duncan’s Multiple Range Test (DMRT) at 5% level of probability using LSD (Least Significant Difference). The study revealed that Annona muricata fruits were dominated by fungal disease symptoms of dry rot, soft rot, anthracnose, powdery mildew and diplodia fruit rot. There was no significant difference between location pairs for all disease symptoms of incidence and severity of Annona muricata, respectively. Fungal diseases at the post-harvest stage pose a threat to storage durability, distribution and market availability of fruits.