Vegetable crop improvement and management : A Pakistan perspective

Vegetable growers are generally small-scale, poor and marginal farmers in Pakistan. Work of agricultural research organizations rarely reaches the farmers due to weak extension services and absence of any coordination between the entities. Therefore, vegetable production technology should be developed keeping the needs of these farmers in view, while meeting the requirements of quality and taste of middle-class society those are major consumers of vegetables. Latest research work stresses, development of technologies for increasing yield, and never kept in view the limitations of the growers. The technologies developed cannot reach the farmers unless effective transfer technology system is available. Therefore, close contact between research and extension scientists should be established. Extension programs on improved technology of vegetables have to be strengthened. Extension workers need to be fully trained in vegetable production technology. Vegetable production programs should also be linked with other rural development programs.

Vegetable crop production in Pakistan is not according to the international standards and internationally demanded varieties. It may be better if national agriculture research organizations move to develop varieties that would be capable to meet the needs of the global market. Development of varieties, rich in nutrients and having resistance against diseases, insect pests, drought, heat and frost will need more emphasis and concerted efforts. Seed of hopeful varieties of vegetables should be produced to ensure regular supply of good quality. It is need for improving and strengthening the seed-producing agencies for better quality seed production and supply.

Emerging areas of science such as biotechnology, bioengineering and tissue culture should be given due importance in research and multiplication of planting materials. Hybrid seed production at lower cost should be encouraged. Vegetable research policies should be focus on solving chronic production problems through development of disease and pest resistant varieties for fitting into various cropping systems in different agro ecological situations. Future strategies in vegetable production must consider increasing demand for export. This has to be supplemented through crop improvement and better management practices that can increase the production to meet domestic requirements and the potential increases in exports.

Vegetables are usually high users of moisture and draw a large share of irrigation resources. The need for high-yielding, short-duration varieties for water use efficiency is much more than low-yielding ones. Water-saving devices like drip trickle or sprinkler irrigation should be encouraged for growing different vegetable crops. Rain fed and riverbed vegetable production should be promoted. Therefore, it is necessary to conduct research on efficient irrigation system under our climatic conditions and to make these technologies available to farmers.

Increasing awareness and sensitivity to environmental pollution and health hazards due to the excessive use of pesticides has stimulated integrated pest management methods in vegetable production which should be pursued. A number of diseases and insect pests seriously affect vegetable production. Cole crops like cabbage and cauliflower are attacked by diamondback moth, cabbage butterfly, cabbage semi-looper and aphids. Aphids are the main pests on root vegetables. Thrips are important in onion.  Fruit and shoot borer is a widely distributed pest mainly on eggplant (brinjal) and is a very serious one. Red pumpkin beetle is a common pest of cucurbits. Melon fruit fly is active throughout the year in various parts of the country. Spotted boll worm and jassids are serious pests of okra. Tomato fruit borer is quite serious throughout the country. Root knot nematodes seriously affect most vegetables, particularly in light soils, and cause considerable damage.

Insecticides dominate in the strategy of vegetable pest management in Pakistan. However, care is required in selecting safe pesticides because residues left on the plants may cause health hazards to people and animals. Integrated management of disease and insect pests in different vegetable crops needs to be developed systematically. Since there is an overuse of hazardous insecticides, research on integrated pest management with minimum use of insecticides has to be undertaken as a priority.

Weed menace in vegetables is worse than for other crops because they are grown mostly on fertile soils with frequent irrigation and heavy manure application. The summer and rainy season vegetables suffer more due to weeds as compared to winter vegetables. Therefore, research with special emphasis on weed control through organic mean is required.

Quality is a combination of agronomic practices, variety characteristics, grading, processing and finally packaging. The absence of even a single factor makes the product inferior in quality or outlook and thus may become less acceptable in international markets. Improper handling of the produce results in a reduction of the market value, keeping quality and food value.

Vegetables are highly unpreserved in nature and have a very limited shelf life. They cannot be stored for a longer period unless they are properly harvested and kept in a temperature-controlled environment. Cold storage facilities are not available in the country that results in very high post harvest losses ranging from 25 to 40 per cent depending on the type of vegetable. Internationally accepted standards of processing and packing are required to be established. All vegetables being exported are either unprocessed or have undergone sub-standard processing and packaging. Research on post harvest value addition of different vegetables has to be undertaken. There may be an increased demand for processed vegetables in the coming years. Technology for proper handling, packing, transporting and storing vegetables to preserve quality needs to be developed locally or introduced.

Unless the productivity is substantially increased, there will be a shortfall in production to meet domestic requirements. Increasing productivity will not be rewarding unless technologies are developed for processing of vegetables, and the establishment of industries at the village level to generate employment and increase incomes of the rural people. Endeavour should be made to initiate research to develop simple agro-based industries that can be established in farming communities. Post harvest technology development of value-added products needs considerable improvement. There is still an increasing demand for both fresh and processed vegetables especially in the Middle East and European markets.