Desiantha/Spine tailed weevil/cereal curculio

Constraint - Spine tailed weevil/cereal curculio

Appearance

• Larvae are white and legless, with yellow head capsules and humped backs

• Adults are small blackish beetles with a pronounced weevil snout

• The wing covers of the females are extended back into two sharp spines that protrude from the rear of the body

Symptoms

• Larvae may hollow out swelling seeds soon after sowing

• They may also bore into the underground seedling stem causing withering and death

• They may also attack one or more tillers of mature plants

Damage

• Seed or seedling deaths result in thinned or patchy crops

• Damage is usually confined to crops sown into existing pasture by minimal tillage

• Yield penatly can occur if populations are not controlled

Control

Insecticidal seed dressings can be used if larvae are detected in the soil prior to sowing. If this treatment is not carried out, damage cannot be avoided and re-sowing with treated seed is necessary. Long term fallows and shortening of rotations so that cereals are sown in alternate years can also be effective.

Links and Resources

I Spy Manual - Desiantha weevil Page 71. Adult and larvae description, distribution, pest status and risk period, host range, damage, and monitoring/sampling. Published 2012.

Insectopedia - Desiantha weevil Description, biology, damage, monitoring, sampling, and control methods. Published 2000.

SARDI - Desiantha weevil 4 page PDF. Identification, damage, life cycle, and cultural, biological, and chemical control methods.