Pest control strategy on sweet pepper farm

Pepper is grown on large scale in many parts of the country because of its high market value [Wilberforce Okwiri, Standard]

It is the holidays season and one of the produce that will be consumed alongside the main dish is sweet pepper. Pepper is grown on large scale in many parts of the country because of its high market value. For it to thrive, farmers regularly apply pesticides to protect the crop from insect attack. However, this leads to development of insect resistance, environmental contamination, worker and food safety issues.

The key to any successful pest management programme is to develop a regular scouting plan to gain information on insect pest populations that may be used to determine if insecticide applications are needed. Monitoring can consist of sampling groups of 10 plants which are randomly selected at five to eight different locations in a field. It is critical to properly identify pests to be controlled and determine their potential for damage. The only way to obtain this information is through routine scouting of fields.

Tomato Fruit-worm

Damage consists of small holes in the stem of the fruit when larvae are small but the larvae are cannibalistic, so there is rarely more than one larva per fruit. The tomato fruit-worm has a wide host range and the attractiveness of peppers for egg laying vary with the time of year. Though it may appear that a calendar-based programme is a preventative strategy, it is not cost-effective. A more effective strategy for managing fruit-worm and armyworms is to monitor fields regularly for signs of insects or damage and to apply an insecticide only when necessary. Field trials have demonstrated that use of the insect monitoring programme will reduce pesticide applications and any damage by the pest. Reduced risk chemicals for fruit-worm control include: Avaunt, Confirm, SpinTor and Proclaim. Other chemicals include: Pyrethroids, Renounce and Coragen.

Beet Armyworm

Egg masses are deposited randomly throughout a pepper plant, often on the underside of leaves. Beet armyworm is primarily a foliage feeder, but they will also attack fruit, usually creating single or closely grouped round or irregularly shaped holes. Feeding damage is superficial, and larvae only occasionally develop inside the fruit. Unfortunately, decay organisms enter the feeding-damaged areas and can rot the fruit. Therefore, it is practical to check young plants regularly for beet armyworm egg masses or small larvae. The presence of beet armyworm larvae can also be detected by shaking foliage over a shake cloth. Reduced risk chemicals for control include: Avaunt, Confirm, SpinTor, and Proclaim. Other chemicals include: Lannate, but pyrethroids are not recommended for control of this pest.

Aphids

Aphids are small, soft-bodied insects that vary in colour from pale yellow to red to green to black, depending on the species, host plant, and season. Direct-feeding damage by aphids is rarely severe enough to kill plants. They pierce plant tissue with needlelike mouthparts, which may result in blossom shed or curling or stunting of new growth. They also produce a sticky material called honeydew that supports growth of a black sooty mould fungus.

If the honey dew gets on the fruit it is difficult to remove making the fruit unmarketable. Aphids are not an important pest in peppers unless too many pesticide applications have been made. Pyrethroid and carbaryl insecticides if used too often can cause an outbreak of these pests in pepper. These pesticides are broad-spectrum and kill many beneficial insects. These beneficial insects or natural enemies, such as lady beetles, lace wing larvae, and parasitic wasps keep aphid populations under control most of the time. If aphid populations increase to damaging levels there are several reduced-risk pesticides available that will give excellent control. They include Actara, Assail, Fulfill, imidacloprid, Platinum and Movento.

Thrips

Thrips prefer to feed on flowers but also occur in flower and leaf buds and, occasionally, on leaves. They are more likely to be found on leaves of vegetables early in the season when they have pine pollen on them. Thrips then feed on this pollen. These early season thrips populations rarely result in any problems later in the season unless several weekly applications of pyrethroids are made early in the season. To determine thrips presence; sample 20-40 flowers while scouting. Thrips will be visible inside the flower using a hand lens, or the flower may be shaken over a piece of paper to dislodge the thrips for observation. The recommended thrips treatment threshold is five thrips per flower. Reduced risk chemicals that will control thrips include: Assail, SpinTor, and Venom.