Tomato Production, Nutritional Value and Its Health Benefits

 Introduction: 

The tomato (Lycopersicon esculentum) belongs to the night shade (solanaceae) family. It is a native of Mexico and was called as tomati. It is believed that from Mexico, tomato found its way to Europe and then to Asia. Tomato is universally a popular vegetable. It can be eaten in fresh or processed form. Tomato is a good source of vitamin A and C, which can help alleviate these deficiencies in the human body. In Pakistan, it is one of the leading and popular vegetables grown. It is used in many forms; fresh as salad and cooked almost with every dish to add taste.  It is cultivated throughout the country. This crop fits in most crop rotations. Cherry tomatoes, plum tomatoes, pear tomatoes, and beefsteak tomatoes are all from the same family. They differ by the shape but also by the color. We can find them red, yellow or orange.

Climate:

Tomato is a frost susceptible crop and loves warm season to grow. Tomato thrives under a wide range of environmental conditions but needs plenty of sunshine, comparatively cool nights with 15⁰C-20⁰C temperatures and warm day temperatures between 25⁰C-30⁰C for optimum production. Optimum nights temperatures exceed 25⁰C and 35⁰C, respectively.

Soil and land preparation:

Tomato can be grown on almost all types of soils, from sandy to heavy clay with a P^H range between 5.5 to 7.5. For early crop, sandy loam is considered and ideal one. Loamy, clay-loam, silt-loam soils containing adequate organic matter are best for high yields. It is essential that soil should be well drained and have good moisture retaining property. Poorly drained heavy soils are not good for cultivation of tomatoes.  If the soil is heavier, special care must be exercised not to work the soil when it is wet, otherwise big clods will be formed.

Seed rate:

Quality seed and true to type cultivar have important bearing upon the yield and uniformity of the crop. Therefore, no pains should be spared in getting the best and pure seed. About 200 grams seed (locally produced) would be enough to produce desired quantity of seedlings for planting one acre of land.

Time and method of nursery sowing:

The time of seed growing is largely determined by the time it is desired to transplant the crop in the field. Plants are usually started in specially prepared seedbeds for raising nursery, several weeks ahead of transplanting time. In the Pakistan, the times of seeding for raising nursery and transplanting seedlings in the field are as under:

Area	Time of Seeding	Time of transplantation
Plains
1.      Open field	February-March	March-April
2.      Under plastic	December-January	January-March
Hills	March-April	April- May
Frost free areas	June-July	July-August

Transplantation/sowing

When the seedlings are 10-15 cm in height, they are ready for transplantation. Transplantation of seedlings in the field should be done late in the afternoon to curtail transpiration of the seedlings, because the heat at that time is less intense. This also allows the seedlings to recover faster. Before transplanting, they should be thoroughly irrigated to minimize root damage. To avoid high mortality of seedlings, they should not be transplanted in a field which is too dry. It is better to irrigate the field just before transplanting the seedlings to improve their chances of survival, recovery from wilting and faster growth. During transplanting, plant to plant distance of 100cm and row to row distance of 20-25 cm should be kept. These distances will allow easy cultural practices throughout the growing period.

Fertilizers requirements:

Animal manure and green manures are very good for improving soil structure and increasing the aeration and water holding capacity. Where well rotten animal manure is available, it should be applied at the rate of 8-12 tons per acre. In case, it is not available, green manuring should be done by growing suitable crop in the year, the land is kept fallow. In order to get high yields and good quality of tomatoes, the soil must be well fertilized. Therefore, before planting the crop, it would be appropriate to have the soil tested to ensure adequate and properly balanced fertilization of the crop. General recommendation for chemical fertilizers application through broadcast before planting is; 100 kg N, 150 kg P₂O₅, 60 kg K₂O per hectare. For better results, full quantity of P₂O₅ and half N and K₂O should be applied before transplanting the seedlings. Remaining half of N and K₂O should be applied 4-6 weeks after transplantation.

Irrigation:

Water requirement of tomato crop for good growth and development is large enough. It would not be possible to grow them without irrigation. Irrigation may be needed as often as every 6-7 days in plains and in hills every 7-10 days on sandy soils during warmer season and at 10-12 days intervals on heavier soils.

Weed control:

Weeds are an important factor in reducing yields of tomatoes. They also serve as potential hosts and breeding sites for many insects and diseases, which attack tomato crop. In a weed-free field harvesting is much easier. All weeds must be eradicated before they become well established. Early hoeing should be fairly deep and close to the plant but the latter ones should be shallow and away from plants to avoid injury to plants roots. Early 2-3 hoeing can give effective controls of weeds.

Disease and insects pests management:

Diseases: The major diseases that cause considerable reduction in tomato yield are Early Blight, Late Blight, Fusarium Wilt and Viruses (Leaf Curl, Lear Roll, TMV). It is necessary to adhere to a strict spray programme to keep the diseases under control in order to get higher production for good quality tomatoes. Once the disease becomes established, it is very difficult to control. Therefore, disease control measures must be adopted from early stages of the crop. Applications must be repeated at 7-10 days intervals. The tomato crop attacked by Early and Late Blights should be sprayed with any of the available fungicides like ‘Dithane-M45/Ridomil Gold/Curzate/Acrobate M-Z/Entrocol at the rate of 2.5-3 gms/litre of water. Fusarium Wilt is a soil born fungal disease. There is no effective chemical control method. Therefore, long crop rotation (4-5 years) with cereals, is recommended. For viruses control, the control of virus vector, like aphids and white fly, is necessary.

Insects: The principal insects attacking tomatoes are aphids, white fly, tomato fruit worm, cut worms and root know nematodes. However, their impact on yield is less serious than that of diseases. The crop should be checked after every 7-8 days carefully to find the signs of insect infestation such as damaged leaves. In this way, attack by most kinds of insects can be discovered in time to take control measures immediately. Proper timing of spray application and complete coverage of plants are the most important factors for effective chemical control. The crop should be sprayed at regular intervals of 10 days.

Aphids and white flies can be controlled by spraying Confidor, Immidachloprid @ 1.5-2 ml/litre, Actara @ 2.5 gms/10litre, of water can be controlled the application. Tomato cut worm and fruit worm can be controlled with the application of Match 1.5 ml/Tracer/Steward 2-2.5 ml/Emamectin Benzuate 2.5-3 ml/litre in the filed or with sprays of the above insecticides. For better management of cutworm, pyrethroid group especially Ripcard/Arrive should be applied @ 60-70 ml/1.5 litre of water with irrigation water as first infestation is observed.

Rot-Knot nematodes (RKN) also attack tomato crop. They cause malformation with the attack on plant roots and the plant becomes stunted. To control them, 5-10 years rotation with cereal crops should be followed. Furadon 3G @ 1Kg gives satisfactory control against RKN at earthing up stage.

Postharvest handling:

Postharvest handling has been discussed in detail in a separate blog “POSTHARVEST MANAGEMENT OF TOMATOES IN PAKISTAN” published on July 31, 2022 on my website “agriproductionmarketing.blogspot.com”

 Nutritional value:

The status of nutritional value of tomato fruit including skin is given in the table below:

S.NO	Items	Value
1	Water	94 ml
2	Protein	1 g
3	Fat	Negligible
4	Carbohydrate	4 g
5	Fiber	0.6 g
6	Calcium	5 mg
7	Iron	0.4 mg
8	Vitamin A potency	Variable (150-1200 IU)
9	Thiamine	0.06 mg
10	Riboflavin	0.04 mg
11	Nicotinamide	0.7 mg
12	Ascorbic Acid	25 mg

Source: Tindall, H.D. (1979). Commercial vegetable growing, Oxford tropical handbooks.

Health benefits:

Tomatoes are not as high in nutrients as other vegetables. But tomato is the leading one in vitamin C. A medium tomato (120 g) contains about 23 mg of vitamin C, which  enhances the iron absorption. This vegetable is poor in calories, only 21 calories per 100 g. On the contrary, it is the perfect vegetable for a diet. Rich in water (more than 90 %), tomato is a diuretic. It will help you eliminate toxins while you are on a diet. Another reason to add tomatoes to your diet is that they have an alkali power. Acidosis is quite common in our society leading to many ailments such as headaches, fatigue, sleeplessness, absorption problems, arteriosclerosis, muscular aches, loss of calcium from the bones etc. Many people rely on anti-acid but many food items would to the same and tomatoes are one of them.

In addition, tomatoes contain lycopene. It is the one responsible for the red color of tomatoes. Lycopene is a phytochemicals on which many studies have been done. With their actual knowledge, researchers agree that this compound have powerful anticancer properties, especially prostate cancer. Bioavailability of lycopene is greater from heated or homogenized tomatoes (sauce, soup) than from raw tomatoes.