Integrated pest and disease management in tree tomato

By Bob Aston

Tree tomato is moderately resistant to pests although minimizing spread of pests and diseases can ensure better returns. Speaking during a Tree Tomato Value Chain Workshop at Sipili Catholic Church Hall, Laikipia West Sub County on September 23-24, 2015, Mrs. Elcy Kigano, Ol-Moran Ward Agribusiness officer said that adopting an integrated pest and disease management could ensure farmers minimize losses due to pest and disease infestation.

“It is always possible to reduce the progress of diseases and keep them at an acceptable level as it is not possible to completely eradicate diseases,” said Mrs. Kigano.

A farmer examining her tree tomato fruits

The two days’ workshop brought together more than 70 farmers drawn from Ol-Moran Ward who had come together to discuss and share best practices on how to enhance farmers production skills on Tree Tomato.

The Arid Lands Information Network (ALIN) through Ng’arua Maarifa Centre organized the workshop in collaboration with Kilimo Biashara Promoters and the Ministry of Agriculture, Livestock and Fisheries (MOALF).

She noted that the fast growing tree tomato or “matunda ya damu” in Kiswahili, prefers sub-tropical climate. She took farmers through control of tree tomato pests and diseases.

Tree tomato pests

Fruit flies are one of the most serious pests in Kenya. They feed on the fruits and other parts of tree tomato. They also lay eggs in fruits. Control is through field sanitation, quarantine and baiting by use of delude mixture of Naturalure with water.

Nematodes are a big problem on sandy soils. They cause serious damage on young trees and can be vectors of viruses. They lead to stunted growth and swelling or knot on roots. Prevention is by removing affected plants, soil fumigation, or soil solarization, keeping the field weed free, planting marigold beside the rows to reduce nematode numbers, practicing crop rotation, rouging, and use of nematicide or extract from neem cake.

Tree tomato worm feeds on the fruits and cause heavy losses. Control is by rigorous spraying and sanitary measures. Biological control is also essential. Green Aphids sac saps on the leaves and flowers. Chemical control can prevent spread of the pest.

Tree tomato diseases

Farmers being taken through tree tomato pests and diseases

A fungus Erysiphe Polygani causes powdery mildew and it results in serious defoliation. A white powdery mould appears on the upper surface of the leaves. The tissue beneath the affected plant becomes reddish brown while leaves turn yellow and eventually fall off. Control is through removing and destroying infected plant parts, spraying 10 percent cow milk, and improving air circulation by thinning and pruning.

Sclerelotinia disease causes black lesions, which girdle stems and cause terminal wilting. Field hygiene and use of fungicide such as Ridomi, Daconil, and Ortiva are ideal ways of controlling the disease.

Ascochyta disease appears as small, round black dead areas on leaves especially mature ones. Black lesions, which girdle stems and cause terminal wilting, are some characteristics of the disease. Field hygiene and use of fungicide such as Thiovit, Ridomil, and Ortiva are ideal ways of controlling the disease.

Tree tomato mosaic virus causes stunted growth, as well as pale mottling on leaves and sometimes fruits. Pulling up and destroying infected plants can prevent spread of the disease.

The farmers were addressing various interventions in Tree Tomato Value Chain that included crop risk mitigation, post-harvest handling, local value addition, linkages to markets, aggregation, and value chain linkages.