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Common cotton stainer
(Dysdercus spp.).

LATE-SEASON

PESTS

by Dr Annette Bennett, Cotton SA

Early- and mid-season pests were discussed in previous editions of the

KatoenSA/CottonSA magazine.

Late-season pests (from 14 to 24 weeks) occur that are small, brown or tan-coloured beetles, may
when bolls are starting to form, when bolls occur as leaf feeders during this period. They are
increase in size and start to crack or open, and sporadic pests and very rarely do any severe
when bolls expose the white fibre inside the boll. damage. Some occasional leaf beetles (Chryso-
It is during this time that sucking pests that usually melidae) that do not do any harm, may occur,
feed on the soft tissue of the young green bolls, as well as predatory ladybird beetles (Coccinelli-
or the young developing seeds inside the bolls, dae). Several beetles occur as sporadic pollinators
occur. These pests are bugs, and not beetles, and on cotton and will be dis cussed at a later stage.
belong to the insect order Hemiptera. Other bugs Late-season sucking pests can be divided into
of lesser importance include the brightly coloured two groups:
rainbow shield bug, Calidea dregei, and some 1. Leaf-sucking pests such as leafhoppers, red
Lygaeidae (seed bugs). spider mites and aphids.
Very few beetles occur on cotton at this late 2. Boll-piercing pests such as common cotton
growth stage, or in the transition period between stainers, green-vegetable stinkbugs, dusky
mid- and late season, while some Nisotra beetles cotton stainers, and mirid bugs.

20 | Katoen SA \\ Cotton SA