Pest

Description

Cut worm (Agrotis spp.)

Affected seedlings by cutting and eating through the tender young plant stems at the soil surface. The larva stage was the most destructive, and every plant attacked by cut worm died. Under high population this pest can damage an entire field if uncontrolled

Beetle-defoliators (Ootheca spp.)

The most common foliage beetles (Ootheca bennigseni) infested the plants starting from vegetative stage 1 to beyond vegetative stage 4 (third trifoliate leaf). The pest caused inter-vein holes in the leaves of young plants. As plant growth continued, the pest damages disappeared, implying that the pests mostly infested young tender leaves

Striped bean Weevil

The Alcidodes leucogrammus was observed on the bean plants but its symptoms were not observed partly because the most destructive stage (larvae) that mostly infest plant stems was absent

Aphids (Aphis spp.)

The winged aphids (Aphis fabae and A. craccivora) affected the plant stems, growing shoots and leaves where they fed by sucking sap. These pests deformed leaves and shoots, eventually retarded plant growth. The pest infestation occurred on plants experiencing moisture stress during the dry periods

Thrips

High populations of white flower thrips (Megalurothrips sjostedti) appeared on bean varieties at flowering stage. Apart from causing flower aborting, the physical symptoms were not visible to the un-aided eye. Other studies have shown that both nymph and adult thrips infest plants causing damage to petals and stigma

Flower and pollen beetle

The mylabrisspp., which feeds on flowers, appeared but they were very few

Bugs

The giant coreid bugs (Anoplocnemis curvipes) were observed between the full vegetative and reproductive stages