The Agriculture Ministry has warned of likely outbreak of pests that ravage food crops.

In a press statement issues today, the State Minister for Agrculture Henry .A. Bagiire said that with the onset of rains, there are likely to be crop pest outbreaks in the different regions of Uganda.

One such pest is the Sweat-potato Hornworm. Reports of the sweet potato hornworm outbreak have come from Amuria, Soroti and Rukungiri Districts as of 30/10/2009.

Description
Adult – Greyish heavy bodied moth with a wing span of 105 to 110 mm. The hind wings and abdomen bear bright pink bands.
Eggs – Nearly spherical and about 1mm, in diameter. The translucent egg has a slightly greenish tint.
Larvae – The first instar of the sweetpotato hornworm has a white body and a black anal horn. Later instars are basically green or brown with prominent, slanted black markings on each side of the body and a black anal horn. The head is also green or brown with 3 dark stripes on each side. A fifth instar hornworm may be 90mm or more in length.
Pupae – The reddish-Brown pupae are about 15mm wide and 64mm long. The large tongue case has a pincher – handle – like appearance.
Host plants – Sweetpotato and the morning Glory are the primary food plants of this hornworm.

Damage: These large worms consume much foliage leaving only bare stems and petioles of plants. Sometimes the hornworms display army worm – like habits of moving together in large numbers. Larvae always hide under large leaves at the base of plants.

Control:
• In small gardens, hornworms can be controlled by picking them from plants and destroying them.
• Chemical control may however, be necessary if the fields are big.
• Contact insecticides like Cypermethrin and Deltamethrin can be used for a quick knock down effect.
• Systemic insecticides like Dimethoate and Imidacloprid can also be sprayed.