Agriculture Reference
In-Depth Information
virally-infected material left in the soil (the virus is capable of surviving many years in
the soil), however it is commonly passed through the use of infected gardening equipment
(tools, pots etc.). It may also be transmitted by humans who have recently been handling
tobacco products. If so, care must be taken to wash hands well with soapy water before
handling any plants. Similarly, all equipment must be sanitized. If an infected plant is seen,
the plant must be removed and destroyed (do not compost or till into the ground).
Tomato Hornworm
- this is a large caterpillar, growing up to 4 inches in length
with a horn-like tail from which it gets its name. These can do immense damage to your
pepper plants. They have a voracious appetite and can quickly devour leaves, initially leav-
ing large holes in the leaf, and in severe cases can eat stems and fruit. To rid your plants
of this bug, keep a close eye on the plant - the color of the bug can blend in with the leaf
(green with white diagonal marks along the side), and simply remove any that are seen.
Treatment can be via an insecticide spray. Alternatively, it has a natural predator in the bra-
conid wasp. The wasp which is harmless to humans, attacks the hornworm laying eggs un-
der the skin. These then emerge as cocoons, looking like grains of rice on the worm. If you
see this, then do not remove the worm, simply allow the cocoons to develop and release
more wasps to attack other nearby hornworms. These wasps can be attracted by planting
nectar-producing flowers which have small florets e.g. catnip, buckwheat or chamomile.
Verticillium Wilt
- this is an infection caused by soilborne fungi. The fungi (pre-
dominantly
Verticillium alboatrum
and
Verticillium dahlia
) infect a number of crops e.g.
peppers, potatoes, tomatoes, eggplant etc. Symptoms include the leaves yellowing and
starting to curl up, with wilting occurring during the day, before recovery at night. This is
more commonly seen during cool weather. The fungus affects the plants ability to take up
water and nutrients, and can eventually kill the plant. There is no treatment available, but
there are many resistant varieties available. If an infected plant is seen, it should be imme-
diately removed and destroyed. To minimize the risk of infection, practice crop rotation i.e.
never grow peppers in an area where other susceptible crops have grown previously.
Disorders
Blossom-end rot
- blossom-end rot is a fruit disorder caused primarily through a
deficiency of calcium and inconsistent watering. This typically manifests itself as a small,
light-brown spot on the blossom end of an immature pepper. This becomes larger, sunken
and leathery in appearance, before turning black as the pepper decays. The infected spot
becomes a site for bacterial infection in many cases. Poor calcium uptake often brought
about by infrequent watering is the most common cause, though poor levels of calcium in
