Here’s some expert advice on weed and pest control for your bell peppers.
- Aphids (mainly Myzus persicae or green peach aphids) are small, soft bodied insects that can be green, black, yellow or pink.
- They are found on the terminal growth ends or underneath the leaf of the plant.
- Once established, an aphid colony can increase rapidly.
- Aphids cause direct damage to plants by sucking the plant fluid or sap from them, causing stunting, yellowing or curling.
- The insects cause indirect damage due to the secretion of honeydew, a sticky substance.
- Honeydew is a growing medium for certain black sooty moulds that can inhibit plant growth or make the fruit unmarketable.
- Aphids are carriers (or vectors) of certain viruses.
- The best control is early detection, so regular scouting is important.
- Their natural enemies include ladybugs, but the reproduction rate of the aphid can outnumber the impact of these predators.
- Applying insecticides as control can kill these natural predators, so keep that in mind when applying chemical control.
- When applying chemical control, keep in mind that the aphids live underneath the leaves and are protected from aerial spray.
- Infestation in a greenhouse can be controlled by good sanitation.
- Weed control around your fields can aid to the control of the aphids.
- Destroy infested crop debris soon after harvesting.
EUROPEAN CORN BORER
- The European corn borer (Ostrinia nubilalis) causes damage to a variety of agricultural crops, including sweet peppers.
- The worm causes direct damage to the fruit by feeding or boring into the fruit, leading to premature ripening and fruit rot.
- The wound caused by the worm is an entry point for other pathogens.
- Their presence can be indicated by small egg masses on leaves or holes in the fruit.
- The damage might not always be visible from the outside.
- Plant your peppers as far away as possible from maize fields to lower chances of infestation. Weed control around the edge of your field is important.
- Chemical control after infestation is difficult since the worm is shielded inside the fruit.
- It is better to apply preventative control.
- The overuse of pyrethroid insecticides as control can lead to problems with aphids, due to the reduction of their natural enemies.
- It is advised to use it in rotation with other insecticides.
- Applying insecticides to control the worm during bloom is harmful and deadly to foraging bees and is not advised.
- It should otherwise be administered when the bees are not active, during the early morning or late afternoon.
- Infested crop residue should be destroyed and ploughing during the fall can destroy most of the overwintering larvae.
- Feeding broad mites causes downward curled leaves.
- Affected leaves develop a bronze colour, especially on the lower side where they become thick and brittle.
- The surface of affected fruit becomes russeted and corky and may become distorted.
- Weeds, like nightshade that serves as hosts for mites, should be controlled to reduce infestation.
- Spotted spider mites reduce the chlorophyll content of the plant, with damages leaves appearing bleached and stippled with small silver-gray or yellow speckles.
- Heavy infestation causes leaves to die off and webbing can be visible on the plant.
- Mites are difficult to control and biological control in the form of the predatory mite Phytoseiulus persimilis is the best form of control.
- Mites don’t like high humidity, so regular watering of plants should reduce infestation.
- Feeding damage from thrips cause distortion and the upward curling of leaves. Leaves become crinkled, and develops a silvery sheen that later turns bronze.
- Signs of damage on the fruit include distortion and russeted streaks.
- The Western flower thrip is a vector for the tomato spotted wilt virus.
- The virus causes yellowing and browning of young leaves, that eventually die off.
- Long streaks of dead tissue appear on the stems extending to the growing tips.
- Large dead streaks of tissue and spots appear on the fruit after infection, while young fruit can completely die off.
- Disease infected plants must be destroyed immediately.
- Thrip resistant cultivars are the best control, as well as mulching with plastic.
- Weeds in your pepper fields negatively affect the yield of peppers in several ways.
- Weeds compete for moisture and nutrients and are hosts to several pests and diseases that can be carried over to the pepper plants.
- Peppers are very sensitive to weed competition, especially 12 to 48 days after transplanting.
- It is therefore important to control weeds in and around your sweet pepper field.