Tomato (Lycopersicum esculentum) is widely grown as the source of income and also consumed vegetables in Kenya. They believed to have originated from Peru, domesticated in Mexico and introduced by Spanish explorers in Europe at around 1544.Here in Kenya, tomatoes were first introduced by European explorers at the sun rise of 20th Century.
Tomatoes are short-lived perennials’ cropped as annuals in the tropics.They are warm season crops of the solanaceae family. Tomatoes can be determinate variety (non-staking) or indertminate variety (staking) or semi indeterminate.
Randah F1
Randah F1 is an early maturing tomato variety that matures 75 days from transplanting. It has excellent canopy to protect the fruits against sunburns and has a good fruit set even under hot conditions. It Produces deep red oval shaped grade one fruits weighing 130-160gms with good storage ability. It is a very vigorous and hardy variety making it ideal for hot growing conditions, with good shelf life. It has high disease resistance package especially fusarium wilt, verticillium wilt and Tomato Yellow Leaf Curl Virus (TYLV).
Optimal Growing Conditions
- Topology-The land should be gently sloping to facilitate drainage during rainy seasons
- Soil Type-The soil should be deep well drained fertile loam soils, it should be well prepared, loosened and broken down well. Test the soil to determine your soil fertility.
- Soil PH-Tomato Randah F1 performs better within a PH of 6.0-7.5.If the PH is low- lime to increase it and if it’s high apply gypsum to lower it.
- Seed Rate-35-40grams of hybrid seed is enough for one acre.
- Site History-Tomatoes should not be planted immediately after potatoes, pepper or brinjals, a 3 month break should be observed to reduce the risk of diseases and the cost of managing the diseases.
Why Grow Tomato Randah F1
- Early maturing variety 75 days from transplanting
- It has excellent canopy to protect the fruits against sunburns
- It has a good fruit set even under hot conditions
- Produces deep red oval shaped grade one fruits weighing 130-160gms
- Very vigorous and hardy variety which makes it ideal for hot growing conditions
- Has firm and big fruits with good storage ability
- It has high disease resistance package especially fusarium wilt, verticillium wilt and Tomato Yellow Leaf Curl Virus (TYLV)
- Has excellent shelf life and high production
- It’s a determinate plum tomato variety
Nursery Preparation
- Make raised beds in rainy seasons and sunken beds in dry seasons of 1m width and of any desired length
- Apply well decomposed manure at the rate of 5kgs per square meter-mix and apply D.A.P at 0.5kgs/square meter
- Make shallow furrows of 15cm apart and 1-2cm deep
- Plant the seeds and cover lightly with the soil and apply mulch
- After sowing irrigate the nursery bed to improve on moisture and then continue watering regularly.
- Germination takes about 7 days, remove mulch and erect the shade above the tender seedlings.
NB: For health seedlings, use Pyramid 700wp-against soil borne diseases plus Loyalty 700WDG-against soil borne pests and Optimizer-helps in breaking the seed dormancy & as stress manager. Apply the three as soil drench during nursery establisbment. Spray Goldchance Super Start NPK 14:28:18+MgO+TE boost health growth of root system of young plants.
Transplanting
- Transplant of seedlings takes 4 weeks after sowing
- Transplant when seedlings have 4-5 well formed true leaves
- Two weeks before transplanting reduce the shade to improve seedling survival rate in the field (hardening off)
- Ensure the seedlings have a ball of soil around the roots when transplanting
Spacing
Tomatoes are spaced at 60cm by 45cm or 60cm by 60cm
NB: Spacing vary according to plant canopy/ variety, nutrients availability in the soil and the nature of crop husbandry practices. Also note that greenhouse spacing is different from open field cultivation, always adhere to recommended spacing by the seed supply.
Fertilizer Application
Apply 2-3 tonnes of well decomposed farm yard manure in an acre at the time of final land preparation.
Apply 75kgs of D.A.P when transplanting, 75kgs of CAN as top dress (30 days after transplant)-5cm below the seedling and 2cm to the sides gives the plant efficient use of fertilizer, 50kgs of N.P.K at the start of flowering and repeat NPK after the first harvest.
Vegetative stage:-Apply Goldchance Super Growth NPK 23:12:12+MgO+TE
Flowering Stage:-Apply Goldchance Super Flowers NPK 21:7:21+MgO+TE
Fruit setting:-Apply Goldchance Super fruits NPK 15:5:35+MgO+TE
Management Practices
- Stake to support the weight of many fruits per each tomato plant
- Weeding-keep the tomato fields weeds free
- Mulch to improve moisture content in the soil
- Prune (if necessary) to reduce vegetative growth that can harbor pests and diseases
Maturity
Tomatoes take 75 days to full maturity
Harvesting
Tomatoes are ready to harvest when the colour of the fruits changes from green to orange or red .Harvest only ripe fruits. When harvesting ensure the highest standards of hygiene-this will ensure a long productive harvesting period. Use bread crates when picking to avoid unnecessary damages on the fruits. After harvesting remove the field heat by cooling the tomatoes under shade.
Health Benefits
- They are good source of antioxidants (carotenoids) which prevents many diseases such as cancer
- They are rich in fibres for digestion purposes
- Tomatoes are rich source of estrogen
- They are low in calories and are excellent source of potassium, Vitamin A & C
TOMATO DISEASES
Early Blight-Alternaria Solani
It is a seed borne disease that results in poor germination of seedlings, its favoured by warm wet conditions.Tomatoes infected with early blight develops small dark brown to black spots on lower shaded leaves, stems and fruits, leaf spots are boarded by a concentric leathery tissue. Spots in fruits often occur near calyx end of the fruits. In seedbed the small plants wilt and die eventually.in older crops, stems death occurs while leaves fall off the crop and fruits drop prematurely.
Solution: Spray Cadilac 800WP to control the disease from spreading
Late Blight-Phytophthora infestans
It’s a minor disease during the dry season however it is most serious during cool moist conditions.spores of plant can transfer the disease from plant to another. The disease forms irregular greenish or water soaked lesions on the leaves, stems and fruits, leaves develop bluish grey patches, turn brown, wither but stay attached to the plant. Fruits develop watery spots on the upper half of fruit. The disease leads to rapid death of entire plant.
Solution: Spray Tower 720WP to cure the disease.
Damping Off-Pythium Sp, Rhizoctonia solani
The fungus is common in moist soils and may survive for several seasons. Infection is through the roots or leaves which are touching the soil or have been splashed by water or rain. Overcrowding, poor drainage, compacted soil and inadequate ventilation increase the chances of seedlings getting infected. Infected seedlings fail to sprout and if they do they have ‘wire-stem’ charateristics.The greatest loss is death of seedlings in the seedbed. Attacked plants are less vigorous.
Solution: Spray Pyramid 700WP or Green cop to control damping off.
Target spot
Description: Brown to black spots first appears on lower leaves, eventually spreading. Spots generally have a series of concentric circles.
Solution: Disease can be carried on seed so only sow disease-free seed. Remove and destroy infected material. Spray remaining foliage and fruit with copper oxychloride.
Fusarium wilt-Fusaruim oxysporum f.sp.lycopersici
Identification: Begins with yellowing on the bottom leaves and works its way up the vine. The vines eventually brown and wilt and may die. Common in hot weather.
Remedy: To confirm infection, split open the stems. If they reveal pink to brown discolouration, fusarium will is present. Maintain a pH of 6.5–6.8 unfavorable for the disease. Keep plants mulched to cool the soil and slow symptoms. Use chariot as soil drench or as foliar spray to control the disease.
Verticillium wilt-Verticillium dahliae
Description: Symptoms are similar to fusarium wilt. Lower leaves dry out and wilt first. The whole plant may die.
Solution: Remove and destroy infected plants. If symptoms persist, grow in pots of fresh potting mix, which is a solution for most wilts. Alternatively spray chariot it works best against the disease.
Bacterial wilt-Pseudomonas solanacearum or Ralstonia solanacearum
Symptoms: Young leaves wilt in hot weather, despite adequate soil moisture. The plant remains green but rapidly wilts and dies.
Solution: To confirm infection, cut the stem at the base of the plant and suspend in water. If bacterial wilt is present, a white slimy substance will be released. There is no cure. Lift and destroy immediately OR Use Chariot and Green Cop to help in sustaining the crop till you complete harvesting.
Septoria leaf spot-Septoria lycopersici
Description: Affects lower leaves first then moves up the plant. Key signs are small yellow spots that turn brown with a black spot in the centre. In an advanced state, the leaves yellow then brown and fall off.
Solution: Regularly remove and destroy infected material. Protect remaining foliage by spraying with copper oxychloride (Green Cop)
Anthracnose-Colletotrichum spp
Signs: Affects ripe or ripening fruit. Shows up as small soft, sunken waterlogged spots. Common in fruit near the ground and spread by splashing water.
Solution: Keep staked with fruit clear of the ground. Remove diseased fruit from plants and soil surface. Spray remaining fruit with copper oxychroxide (Green cop) as ripening begins. Use crop rotation. Seed in diseased fruit will be infected so use healthy seed for new crops.
Tomato Yellow Leaf Curl Virus (TYLCV)
Signs: The disease is neither seed borne nor mechanically transimitted but its spread by whiteflies. It’s also favoured by high temperatures and low rainfall which whitefly populations. Infected plants become stunted and branched, leaves are chlorotic and curl upwards, and plants have very few flowers hence few fruits.
Solution: There is no cure. Lift and destroy affected plants. Avoid replanting in same patch. Sterilise tools and wash hands. Plant disease-resistant varieties such as tomato Randa F1.Control whiteflies by spraying Taurus 500SP
Common Nutrient Deficiencies in Tomatoes
Nitrogen
Symptoms: Stunted growth. Older leaves are yellow. Younger leaves turn pale green.
Remedy: Spray Goldchance Super Growth NPK 23:12:12. Add well-aged compost or manure. Also diluted fish emulsion or small amounts of dry chicken manure. Don’t overdo it. Too much nitrogen encourages lush leaves with little fruit.
Phosphorus
Signs: Stunted growth. Purpling leaves, particularly the undersides.
Solution: Check your soil pH – phosphorus is unavailable when pH is too high or too low. Treat accordingly rock phosphate. Spray Goldchance Super start NPK 14:28:18 to correct the deficiency.
Potassium
Description: Brown scorching on the leaf margins and chlorosis (yellowing) between the leaf veins. Blotchy ripening in fruit.
Solution: Use Goldchance Super fruits NPK 15:5:35 foliar spray and lightly sprinkle rock potash or wood ash around the plant. Water in. Add well-aged manure and compost.
Iron
Symptoms: Pale yellow leaves, or interveinal chlorosis, particularly of the younger leaves.
Solution: Check your soil pH as it may be a sign of alkaline soil. An application of sulphur may assist. A foliar spray of iron chelates will help green up the leaves within a couple of weeks.
Calcium
Signs: Blossom-end rot or darkening at the base of the fruit. Browning around the base of the leaves.
Solution: Spread agricultural lime and water well to correct the deficiency. Spray Ferrari Gold as foliar for quick correctional results.
TOMATO INSECT PESTS
Cutworm-Agrotis SSP, Peridroma saucia
They chew through stems of seedlings overnight, killing them. it’s a greyish,hairless worm of waxy appearance.it curls up into a little ring when held in the hand, it’s found in the vicinity of cut plant, it a caterpillar of the noctuid moth. They hide in the soil during the knight and only emerge at night to feed on the young plants.
Solution: Use Loyalty 700wp as soil drench.
Aphids-Myzus persicae, Aphis gossypii
Clusters of small sap-sucking insects, usually under leaves. Will reduce plant vigour and can spread plant diseases. They are delicate pear shaped soft bodied insects with long legs and antennae. They are usually green, yellow, dark or black in colour with or without transparent wings. Heavy infestation causes yield losses and sunburn.
Solution: Spray Pentagon 50EC to control Aphids
Whitefly-Bemisia tabaci
Tiny white-winged sap-sucking insects that congregate on the undersides of leaves, reducing plant vigour. Adults fly from plants when disturbed but quickly resettle.They are small insects about 1-2mm long, they hold their wings somewhat roof-like over the body,wings don’t meet over the back but have a small space separating them
Solution: Sticky yellow traps hung amongst crops will attract and control large numbers. Covering plants early with fruit fly netting will reduce attack. Spray Taurus 500sp plus Integra (sticker) to control Whiteflies.
African Bollworm-Helicoverpa amigera
They enter fruit at a young stage. Fruit continues to grow with the caterpillar developing inside. Rot occurs as fruit ripens. Adults are brown moths which fly at night laying eggs about 0.5mm on plants parts. At hatching the larvae are creamy white caterpillars with a black head. They vary in colour from yellowish to green to black with white lines on the back.
Solution: Spray plants with Baciguard 16000 WDG or cover crops with fruit fly netting to keep adult moths from laying eggs on plant material.
Leaf miners–Liriomyza spp
The adults are small black and yellow flies about 2mm long.They lay eggs which hatch into small larvae that feed by mining between the upper and lower epidermis of the leaves making a tunnel as they move a long.The act of laying eggs and feeding on leaves can kill seedlings and in older plants allows fungal diseases to enter.Leafminers have the ability to develop chemical resistance very fast.
Remedy: Spray Alonze 50EC to kill the pests.
Spider Mites –Tetranychus ssp
They are minute reddish brown “spiders” with four pairs of legs of equal length and with an oval body.Their legs are creamy usually on the leaf surface.They protect themselves from predation by webs on the underside of the leaves.
Solution: Spray Alonze 50 EC alternate with Profile 440EC to control mites.
Root-knot Nematode –Meloidogyne ssp
They are pear-shaped thread like worms about 0.01inches long,They live in the soil and get food from sucking root sap causing root knots also called galls.They can be seen by hand lens when the galls are cut open.The galls interfere with movement of water and nutrients effectively,Infected plants are less vigorous,stunted and respond poorly to fertilizers.Nematode infection makes it easier for diseases to infect the tomato plant.
Solution: Use Adventure 0.5GR at rate of 5gms per hole/plant.
Thrips – Frankliniella ssp
These are minute insects less than 1mm long in length with four long, narrow fringed wings.The immature stages are yellow in colour.Adults are usually dark with a habit of turning up the tip of the abdomen.They feed by rasping plant surface causing small silverfish blotches, they feed on lower leaf surface, buds flowers and fruits. When flower buds are attacked floral abortion occurs and the affected fruits are of poor quality. They are vectors of viruses like tomato spotted wilt virus.
Solution: Spray profile 440 EC alternating with Alonze 50EC to control thrips.
PHYSIOLOGICAL DISORDERS IN TOMATOES
Blossom End Rot
The problem is caused by calcium deficiency, any rapid change in water and poor root development, Use of nitrate fertilizers and high humidity can worsen the problem. It begins as tiny water soaked area at the blossom end of the fruits; it later enlarges and become sunken. The sunken part of the fruit turns black turning the bottom of the fruit brown.
Solution: Apply calcium lime-stone or dolomitic limestone, Spray Ferrari Gold which has Ca 17%, N 10% Mg 4%, Bo-0.1% as faster remedy of the problem.
Catface
This condition is associated with faulty pollination and cold weather. High nitrogen levels and pruning can increase this problem. It’s characterized by deep cavities into blossom end of the fruits. It manifests itself as kidney shaped with elongated blossom scars.
Solution: Plant cultivars that are not susceptical to the problem, water tomatoes frequently, avoid planting tomatoes in cold seasons/periods and avoid applying nitrogen in excess.
Growth Cracking
These are cracks that appear when the fruits are developing. They occur mainly when the fruits are approaching maturity. They are either radial or concentric. Cracks are caused by fast growth in high temperatures and high moisture levels, dry periods followed by heavy rain or irrigation during ripening.
Concentric or radial cracks form at the stem end of the fruit, cracks reduce the market value and provide entry point for pathogens.
Solution: Manage irrigation programs to avoid fluctuations in temperatures, grow varieties that resists cracking and avoid over-use of nitrogen fertilizers.
