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TOMATO (Lycopersicon esculentum)
Tomato is a vegetable crop commonly grown by peasant farmers in West Africa. The fruit called berry when ripe can be eaten raw, used for soup or stew preparation, or in preparing vegetable salad and other food.
Land preparation
Land is cleared with cutlass and ridges are made with local hoe, or land can be prepared by ploughing, harrowing and ridging.
Varieties/Cultivars: These include money-maker, valiant, pork, dwarf gem, marglobe, Ife plum, bonita, roma, local varieties.
Climatic and Soil Requirements
Tomato requires a temperature of 20°C – 25°C, rainfall of 50 – 125cm, high level of sunshine and a well-drained loamy soil, rich in organic matter.
Method of propagation: These are seeds which can be propagated by drilling or broadcasting.
Planting Date: Tomato is planted in early September and October.
Seedrate: 5 – 10kg of seeds/ha.
Nursery Practices
- It is done on ground, beds or seed boxes/trays with top soil, thoroughly mixed and watered.
- Seeds are sown in drills, 5cm apart and 2.5cm deep.
- Shading, mulching, weeding and watering are done.
- Nursery lasts for three weeks when the plants are at the three-leaved stage.
Spacing
- 60cm x 60cm without staking.
- 50cm x 30cm with staking.
Transplanting: Seedlings with four to five leaves, 15cm – 20cm tall and about 25-30 days old are transplanted with ball-of-earth. Holes measuring 5cm deep are dug and seedlings are transplanted to the field either in the morning or evening.
Cultural Practices
- Weeding: This should be done at regular intervals.
- Watering: Soon after transplanting, seedlings should be watered every morning and evening till the plants are able to stand on their own.
- Fertilizer Application: Apply N.P.K. 15:15:15 fertilizer to each plant three weeks after transplanting at 250kg/hectare; or apply any organic manure like compost or farmyard manure at 3040 metric tonnes per hectare.
- Staking: Provide stakes to enable plants to stand erect and prevent lodging. Stems are tied or trained to the stakes. Staking allows for good fruiting and keeps fruits from disease attack, arising from contact with soil. Staking should be done before flowering.
Maturity period: This occurs between two to four months after planting.
Harvesting: Matured or ripe fruits are harvested by handpicking and stored in dry, cool place. Harvesting starts as from two months.
Processing: Tomato is either used or consumed after harvesting, or it can be processed into tomato juice or paste.
Storage: It can be stored as canned paste.
Pests of Tomato
1) Cricket and Beetle: These eat up leaves or cut off young seedlings and cause damage to crops.
Control
- Spray with insecticides, e.g Vetox 85.
Diseases of Tomato
1) Fusarium Wilt (root rot): It is a fungal disease (Fusarium oxysporium) which is spread by wind.
Symptoms: These include gradual dropping of leaves followed by wilting and drying up of leaves of the whole plant.
Control
- Treat soil with copper fungicide.
- Practise crop rotation.
2) Root knot disease: It is caused by a nematode. Roots develop galls or knots with yellow, curled leaves and dwarf plants.
Control
- Treat soil with nematicide.
- Plant resistant varieties.
- Practise crop rotation.
3) Bacterial wilt: This is caused by a bacterium called Pseudomonas solaraceurium. It is transmitted through the soil and it attacks roots.
Symptoms: Symptoms include wilting of the leaf, death of the affected plant, and slimy exudation from the stem.
Control
- Practise crop rotation.
- Avoid infected soil.
4) Leaf spot disease: This disease is caused by a fungus called Chadosporium spp. It is an air-borne disease whose spores are deposited on leaves.
Symptoms
- Symptoms include circular white patches which appear on the leaves.
- Dead spots also appear on the leaves.
Control
- Use copper fungicides like Perenox and Bordeaux mixture.
- Practise crop rotation.
- Use resistant varieties.