A Portable Deep Learning Based Platform for Passion Fruit Disease Identification
Disease Knowledge Center
Passion fruit plants in Uganda are affected by a range of fungal and viral diseases, which potentially cause high plant and yield losses. Accurate disease diagnosis of passionfruit diseases is essential for effective control. Disease identification is difficult, particularly for farmers that are new to the industry. This page provides information on the most common passion fruit diseases in Uganda.
This is a viral disease. Woodiness virus belongs to the Potty Virus group(PWV). The disease is spread by sap sucking insects such as aphids, mealy bugs, and mites, where they feed on an infected plants and then to healthy plants. Pruning tools can also spread viruses. The viruses are not spread through seeds. The disease affects the plant at all stages from nursery to mature stages. [1]
Chemically, this disease cannot be controlled using fungal chemicals to spray the affected plants. However Husbandry practices can be carried out and these include;
This is a fungal disease caused by Alternaria passifloracea. The disease affects the passionfruit leaves, stems, and fruit. it is triggered by a humid microclimate around the plant, this microclimate could be due to unpruned trees, trees that grow under a shade, fields that are established in the swamplands, congestion in the nursery. [1]
This disease can not be controlled chemically. However, husbandry practices can be used and these include;
This is a soil-borne fungal disease caused by the fungus, Fusarium solani. The rotting of the plant starts at the collar hence the name collar rot. The disease is most common in wet and cold seasons. [1]
Chemically, this disease cannot be controlled using fungal chemicals to spray the affected plants. However other ways can be practiced and these include;
Virus is transmitted by white fly (Bemisia tabaci) from infected passion flower to bean and from the bean to bean but not from the infected bean to passion flower. Virus is not transmitted by sap inoculation or by seeds of infected plants. [1]
Passion fruit Yellow Mosaic Virus (PaYMV) is transmitted by White fly (Bemisia tabaci) from infected passion flower to bean and from the bean to bean but not from the infected bean to passion flower. Virus is not transmitted by sap inoculation or by seeds of infected plants. The virus is not apparently transmitted by seeds. Diabrotics speciosa, a polyphagous beetle, found occasionally in passion flower plantations is the natural vector of PaYMV. [1]
Fusarium wilt is serious fungal disease in Passion fruit particularly the local purple passion fruits. The disease is soil borne, meaning that the fungus lives in the soil from where it attacks the rooting system of the plants. Inside an orchard, it is spread by soil movements by running water or irrigation water. The disease intensity is greater in sandy soils and favoured by high temperatures and relative humidity, spreading upwards along the stem and one can easily recognize brown patches scattered on the stem. [1]
Pathogen Xanthomonas axonopodis pv. passiflorae, an aerobic gram-negative rod which forms bright yellow colonies in the culture medium is the causative agent Infection occurs through natural openings; Disease severity increases with high temperatures and relative humidity. Local dissemination of the bacterium is favoured by wind, rain, irrigation and also through infected seedlings. [1]
The preventive measures that can be adopted to control bacterial spot include;
Optimal disease control involves the prevention of infection, minimizing the inoculum (sources of infection), and breaking the disease cycle. These steps can be achieved by three essential control strategies: (1) canopy management, (2) orchard hygiene, and (3) a fungicide spray program. [1]
Fungal diseases need extended wet periods for sporulation, spore germination, and infection to occur. Prune and open up the canopy to promote rapid drying, make the microclimate unfavorable for fungi, and avoid dense tangled canopies that trap dead leaves, which can be inoculum sources. [1]
Passionfruit plants are subject to infection by a variety of diseases throughout the year and minimizing inoculum sources by proper orchard hygiene is essential for effective control. Reduce sources of inoculum by:
A preventative fungicide program is recommended. It is too late to commence once symptoms appear. Fungicides are applied following the seasonal stages of the crop and the likelihood of infection by pathogens.