Diseases

Mode of transmission

Signs and symptoms

Damage caused

Control Measures

Bean Mosaic Virus

- Aphids

-Stunted growth

-leaves are mottled

-Total yield loss

-Planting resistant crops

-Planting certified seeds

-Planting beans in isolated area

-Spray insecticides e.g. Dimethoate and Supermetrine

Anthracnose

- Fungus

-Dark brown spots on leaves

-Leaves darken and veins collapse

-Yield losses up to 100%

-Use a 3 year crop rotation with cereals

-Burry crop residues

-Use of tolerant varieties

-Intercropping

-Spray Dithane M45

Angular Leaf Spot and web blight

-Bacteria

-Grey sports appear on leaves

-Grey spots become dark brown

-Forms a web on a plant and lead to defoliation

-Yield losses up to 100%

-Use clean seeds

-Bury the infected debris

-Crop rotation

-Spray Daconil

Common Bacteria Blight

-Bacteria

- Water soaked spots on the lower side of the leaves

-Stem easily break

-Yield losses up to 70%

-Use tolerant varieties

-Crop rotation

-Bury infected residues

-Timely planting

-Use clean seeds

-Weeding

Pests

Symptoms

Damage caused

Control measures

Bean weevil

-

-Attack dried beans and can be serious pests in dried beans

-Feeds and contaminates the dried beans

-Larvae may nearly consume the entire bean

-Sanitation

-Planting weevil free seeds

-Eliminate potential sources of weevils

-Spray Demethoate

Bean Beetle

-Holes on the plants

- Reduces yield by feeding on the leaves

-Feeds on leaves

-Spay Carbaryl

Bean Aphid

-Plants loose greenness and they look black

-Seedlings wilt and die

-Uses slender mouth parts to pierce leaves, stems and other parts to suck fluids

-Causes direct damage to the beans

-Reduces yield

-Spray Dimethoate

Bean Stem Maggot

-Stunted growth

-Stem becomes dry and swollen

-100% yield loss if larvae densities are high.

-Crop rotation

-Adjust time of sowing

-Practice good water management

-Planting early cool wet and high altitudes