Pineapple plant affected by the wilt disease
Pineapple is one of the most important fruit crops cultivated in Guyana for both domestic and export purposes. However, the fruit can encounter many obstacles during its cultivation. The National Agricultural Research and Extension Institute (NAREI) is recommending that farmers take preventative measures to protect their crops.
Pineapple is being targeted as a crop for further expansion under the Ministry of Agriculture’s Agricultural Diversification Programme (ADP).
Pest control/ management
Dr. Oudho Homenauth, NAREI’s Chief Executive Officer (CEO), pointed out that ants and mealy bugs pose a serious threat to pineapple cultivation; a combination of the two can be a big problem. According to NAREI, mealy bug colonies are tended by ants, which protect them by making shelters of soil around the mealy bug. Initial control should be directed against the ants to ensure success. When the ants are controlled the shelters collapse and control measures can be directed towards the mealy bug. Ants can be controlled either by drenching their nests with insecticide or by applying bait.
Dr Homenauth explained that spraying the plants in the field after the ants have been eliminated can control the mealy bugs. Insecticide application is recommended throughout the plant growing cycle to keep the pest under control. The frequency of these applications depends largely on the level of pest infestation, but is particularly important at the early plant growth stage during the fruiting season.
Information put together by NAREI’s experts also shows that pineapple can be also be attacked by a specific butterfly resulting in the gummosis disease. This disease follows the attack on the fruit by the Thecla butterfly and is characterised by the exudation of an amber coloured sticky material or gum from the wound. Control of the disease is directed at controlling the Thecla butterfly. The control of the pest is achieved by the application at the time of flowering and during the blooming period, of the same chemicals used to control the mealy bug. As such the timing of application could be so coordinated to control both pests simultaneously.
Disease management
Meanwhile, the Scarlet Tip’ condition is also a common disease that affects pineapple plants. There are four stages of this disease. Dr. Homenauth noted that symptoms include a pale pinkish colouration of mainly the middle of the plant leaves. This discolouration spreads outwards towards the leaf margin and upwards towards the leaf tip. Eventually such leaves curl downwards at the margin while the tip remains erect. Irregular spots are sometimes observed on the leaves. The method recommended for the control of this disease is burning all diseased plants as soon as they are spotted in the field.
Wilt, another disease is caused by a virus/toxin associated with the mealy bug. The most visible symptom is a bright bronze to red colouration of the leaves of the young plant or a pinkish and/or yellowish colouration of older plants. Any fruit produced by these plants is usually small and/or distorted.
Additionally, Internal browning is a common post-harvest disorder affecting pineapples in Guyana. The symptoms begin with grayish translucent areas at the base of the fruit near the core, which eventually darken and in severe cases causes the entire internal flesh to turn brown or black in colour. This can be controlled by waxing the fruit.
Mealy bug
In Guyana the major pineapple producing areas are Regions 3 and 4. According to NAREI, yields range between 15.0—18.0 tons per hectare (ha). The institution believes that with improved technology, yields can be as high as 30 tons/ha.
Farmers are advised to invest in this type of cultivation because it can be very economical, with profitable markets in the Caribbean.
Pineapples are used for in many different ways; it can be consumed as chunks, slices, juices, jams, and syrups. Also the waste from processing the fruit can be further converted to sugar, wines, vinegar, and animal feed.
Regale Male Scarlet Tip Butterfly