**8.3 Irrigation**

Ghanaian farmers traditionally rely on rainfed cultivation to grow their crops. However, between the 1960s and the year 1980, growth of irrigation started

and a total of approximately 19,000 ha of irrigated land had been developed and in 2007 the area in irrigation had expanded to 33,800 ha. Irrigation systems observed in Ghana are mainly initiated and developed by the Ghanaian government or various nongovernmental organizations (NGOs), and emerging systems, which are initiated and developed by private entrepreneurs and farmers. Ghana Irrigation Development Authority (GIDA), controlled by the Ministry of Food and Agriculture manages irritation and is the only public organization connected directly to irrigation development and management in the country. GIDA has developed 22 irrigation project districts of varying sizes covering a total area of 8,800 ha across the country. Since its establishment, GIDA has developed and managed public irrigation systems utilizing government subsidies, and public funds to cover staff costs. As part of structural adjustment, GIDA's budget was dramatically reduced and that resulted in difficulties in managing all the 22 public irrigation districts sustainably [65]. However, in order to maintain irrigation activities, a "Participatory Irrigation Management (PIM)" was introduced, whereby beneficiary farmers and others could manage the irrigation facilities during their vegetable and other crop production. Generally, the watering cans, buckets, motorized pumps with hosepipe, surface, and sprinkler irrigation methods, are mostly being used by farmers in the vegetable production areas in the country [7, 66]

## **8.4 Organic farming technology**

The Ghana Government accepts the premise that national food security can only be realized through the wide-scale introduction of modern commercial agriculture and that such modernization will spearhead the development of the economy [67]. Health concerns with respect to vegetable production have meant that organic farming is gaining popularity in many countries, including Ghana. The factors influencing the adoption of organic vegetable technology in the country are based on extension contacts and farmers' engagement in training workshops, formation of farmer-based organizations (FBO), and farming experience over the past years. Organic vegetable farming can be used as a strategy to improve food production and reduce poverty in the country.

#### **8.5 Pest management**

The advent of synthetic insecticides revolutionized how insect pests were managed through a leap from suppression to "kill them all". Increasing reports of insect pests building resistance to these insecticides prompted the adoption and promotion of all available management measures through careful planning. These complementary options include natural enemies, microbials, botanicals, cultural practices, and synthetic insecticides. Similarly, the management of diseases solely based on synthetic chemicals has shifted to the adoption of complementary approaches. Thus, current pests and diseases management strategies involve the adoption of a multifaceted approach; integrated management. The high vulnerability of vegetables to pests and diseases makes this aspect of the production very critical. For this reason, developing new complementary pests and diseases management technologies is crucial for the sustainable yield of vegetables. Some of these technologies accessible to the Ghanaian vegetable farmer are discussed below:

*Microbial pesticides*: They contain one or more microorganisms (e.g., fungus, bacterium, virus, nematode, or protozoan) as active ingredients. They may be target-specific or broad-spectrum and tend to be environmentally friendly since they are naturally occurring. Common microbial pesticide formulations available for vegetables include *Bacillus thuringiensis, Metarhizium anisopliae, Beauveria bassiana*. Plant-incorporated protectants which involve incorporating genetic material

*Harnessing Technologies for Vegetable Cultivation: A Panacea for Food and Nutrition Insecurity… DOI: http://dx.doi.org/10.5772/intechopen.101877*

into a plant (i.e. Genetically Modified Organism) to offer insecticidal property are not yet approved for use in Ghana.

*Botanical pesticides*: A number of plants-derived products have exhibited insecticidal activity against a number of pests of vegetables. The most popular are the neem products with Azadirachtin as the active ingredients. [68] Provided an exhaustive list of plants with insecticidal properties, including those suitable for vegetables.

*Natural enemies:* Pests are normally perceived by many as inimical organisms that just increase in number without any natural check. On the contrary, pests are not completely immune from the adverse effects of other animals. There are a good number of animals, predators and parasitoids, that attack and kill pests in every vegetable production system. Predators seize and kill pests while parasitoids normally inoculate their immature forms into different developmental stages (eggs, larvae, pupae, or adult) of pests. All these help suppress pest populations below the economic threshold to maintain a balanced production system. Although naturally, pest populations may surge up irrespective of the natural enemies, anthropogenic disturbances such as the use of synthetic insecticides, monocropping, etc. are the main sources of pest outbreaks. Strategies to boost natural enemy populations and their attendant services include intercropping, mixed cropping, crop rotation, and leaving strips of flowering or natural vegetation along boundaries of vegetable fields.

*Pheromone lures*: This employs the use of pests' own chemical communication against them. The most commonly communication chemicals used in agriculture are sex pheromones. Although a wide array has been developed, particularly for monitoring and decision making, only a few are available in Ghana. The common pheromone lures for vegetables in Ghana, mostly used at the research level are that of a tomato leaf miner (*Tuta absoluta*) and diamondback moth for tomato and cabbage respectively. Nevertheless, there is a great prospect for mass adoption.

*Sticky traps:* These are color, mainly yellow, flexible plastic cards with the sticky surface to trap flight-capable insect pests. They are relatively costly since they are scarce locally. However, homemade sticky traps can easily be created by cutting yellow plastic strips (10 × 25cm) smeared with grease or petroleum jelly. Traps are hung on a pole just above the height of the crop. Traps can be reused by scrapping off trapped insects when the surface is almost filled up. A number of the above strategies can be combined to suppress pests in vegetables, and the inclusion of synthetic insecticides is always considered as the last resort.

#### **8.6 Diseases management**

Many vegetables are prone to diseases and their impact on production can be dire. Causative agents of diseases range from fungi, bacteria, and viruses. Understanding of disease triangle which consists of the host, the pathogen, and the environmental condition is important in managing these problems. A break in the link of the triangle truncates the perpetuation of the disease [69]. Thus, effective management of diseases in vegetables involves the use of disease-free seeds and varieties that are tolerant/resistant to the major diseases that are prevalent in the production enclave. Although general climatic factors are beyond the control of the vegetable grower, a micro climate that reduces the survival of the causative pathogen can be provided. An example is using well-drained soil and avoiding weed growth on the cropped field. In situations where a vector is involved in the transmission of the disease, it is important to manage the pest. A typical example is white flies, which transmit viral diseases.

Other intervention, which has also become popular among growers is the use of pesticides such as fungicides, bactericides, etc. These may be applied as preventative or curative depending on the active ingredient and thus the time of application is very crucial.
