Tomato belongs to solanaceae family. It is one of the very popular vegetables in Pakistan. It is widely used in salad as well as for culinary purposes. The popularity of tomato and its products continue to rise as it contains significant amount of vitamin A and C.
Trends, area, production and yield
There has been a progressive increase in area and production of tomato in Pakistan. In 2004-05, the area increased to 41.4 thousand hectares, production 426.2 thousand tons and yield was 10.3 tons / ha. The data since 1999-00 are as follows.
Table 1. Area, production and yield of tomato in Pakistan (1999-00 to 2004-05)
|Year||Area (000 ha)||Production (000 tonnes)||Yield (t/ha)|
The average shares of the provinces in the over all area and production of tomato, based on the data of 2004-05, are given in the following table.
Table 2. Shares of provinces in area and production of tomato (2004-05)
|000,ha||percent share||000, tonnes||Percent Share|
Time of sowing
Due to varying climatic conditions, there is a wide range of sowing time of tomato in Pakistan. There are three main crops that are as under.
For early crop, nursery is sown in July-August, transplanted in the field in August-September and the harvesting of the crop starts in November.
Mid season crop
Nursery is sown in September, which is transplanted in October and harvested in December/January.
Main season crop
Nursery is sown in mid-November, transplanted in February and the crop is harvested in May-June.
Seed Rate and Nursery Raising
300-350 g seed is required to prepare nursery for one hectare. Seed is sown in raised beds prepared with a growing media of farm yard manure, soil and sand with the ratio of 1:1:1 and covered with thin polyethylene sheet. The seeds will germinate in 7-14 days.
Remove polyethylene sheet after seed germination.
The seedlings should be harvested to withstand the out-door conditions with as little shock as possible. The hardening may be accomplished by lessening water supply. The process may require 7 to 10 days. The seedlings are transplanted on the both sides of 1.5 meter wide beds with a distance of 50 cm on the rows.
The plants are irrigated just after transplanting. Irrigation with an interval of 7-8 days is recommended. The irrigation interval can be decreased from 5-6 days when weather is too hot. Irrigation water should be given with care so that beds should not be submerged into water.
Manure and Fertilizers
In tomato crop, high yield can be obtained only if well balanced fertilizers and manure are supplied to the plants in time. Well rotten farm yard manure should be applied at the rate of 25-30 tons per hectare, at the time of land preparation for maintaining proper physical conditions and fertility status of the soil. General recommendation for chemical fertilizers is 75 kg of nitrogen, 60 kg of phosphorus and 60 kg of potassium. Half amount of all fertilizers and full amount of farm yard manure are incorporated into the soil at time of land preparation. Remaining half amount of fertilizers is split into two doses and applied as side dressing to the plants one month after transplanting and after first picking of fruit.
The stage of ripeness at which the tomatoes are harvested depends upon the purpose for which they are grown. For canning and processing, the fruit is harvested when it is fully ripened on the vines. For local markets, it is harvested in the hard ripe and pink stages. For the distant markets, the fruit is picked in the mature green or turning pink stage. For the home use, tomato may be left on the plants until they are fully colored.
Tomatoes can be kept for storage for only a short period of 7-10 days. Fruits picked at semi-ripe stage and placed in well ventilated store with low humidity and at 1.1-2.2 °C will remain fit for human consumption for about three weeks.
It is caused by the fungus Fusarium oxysporium f. lycopercici. It is characterized by a yellowing and drying of the leaves progressively from the base upward, and by discoloration of the vascular tissue. It is controlled by the use of diseased resistant cultivars and disease free seed. The planting should be done on disease free beds. The crop rotation should be followed and diseased plants should be disposed of.
It is caused by Pseudomonas solanacearum. The diseased plants wilt during the day and partially recover at night. Freshly cut stems exude a gummy, yellow mass of bacteria. It can be controlled by planting disease free plants, removal of diseased plants and following crop rotation.
Early blight is caused by Alternaria solani, the fungus that causes early blight in potatoes. To control it, sow only treated seed from disease free plants, practice sanitation by deep ploughing and follow crop rotation.
It attacks nursery seedlings at the surface of the soil, causing the stems to shrivel and the plants to topple over. Treat the seed with thiram and avoid over irrigation.
The important viral diseases of tomatoes are tobacco mosaic virus and cucumber mosaic virus. The diseases are highly infectious and readily spread by insects and cultural operations. Sanitation and control of vectors can reduce the spread of viruses.
Ref. Various sources