Native budworm
Helicoverpa punctigera
Also known as native budworm and heliothis, Helicoverpa punctigera is a major pest of pulse and canola crops. It causes yield loss through seeds being wholly or partly eaten and quality downgrades because of unacceptable levels of chewed grain or fungal infections developing because of the caterpillar damage. In vegetable crops, they can feed on the leaves, buds flowers and pods, while older caterpillars burrow into fruit, pods and heads of crops. In addition, their excrement can be a contamination issue.
Description
When less than 15 mm, caterpillars are light brown with dark heads. Once they grow larger, the bodies darken in colour and two distinctive stripes develop. They can be up to 50 mm long and vary in colour from green to orange to dark brown, sparsely covered in fine bristles. In pod crops, they are often seen with their heads inside the pod.
Adults are a stout moth with patterned brown wings spanning up to 40 mm that are held flat across the body. The hind wings are pale brown with dark edges.
Of the podded broadacre crops, moths are most attracted to lentils, followed by field peas, faba beans, chickpeas, lupins and then canola crops.
Control
Field pea, chickpea, lentil and faba bean crops are most susceptible to attack from the beginning of podding while in lupins and canola, the pods only become attractive to the caterpillars once they begin to hay off and lose their green coloration. Therefore, field pea, chickpea, lentil and faba bean crops should be monitored from first podding.As part of a successful IPM program, monitor caterpillar numbers in broadacre crops by using sweep nets or a beat sheet and opening a number of pods to measure the number of grubs inside before making a decision on whether to spray. In horticultural crops, targeting native budworm at first signs of infestation is recommended, which in some cases is just after the eggs have hatched.
When threshold levels are exceeded, native budworm can be controlled with insecticides, including biological insecticides such as Bacillus thuringiensis and nuclear polyhedrosis virus. However, correct timing and thorough coverage are essential to achieve good control.
Decis Options© is registered for the control of native budworm in broadacre and horticultural crops including canola, cereals, lupins, chickpeas, field peas, faba beans, linseed, safflower, vetch, cotton, sorghum, soy beans, navy beans, mung beans and other seed and pod crops, berry vegetables, sweetcorn, sunflowers and tomatoes.
Belt© is registered to control native budworm in a range of horticultural crops including brassica vegetables, brassica leafy vegetables, chia, fruiting vegetables (i.e. cucumbers, tomatoes), herbs, leafy vegetables, stalk and stem vegetables (i.e. celery) and strawberries.
References
AUSVEG (Viewed October 19), ‘Caterpillars’ https://ausveg.com.au/biosecurity-agrichemical/crop-protection/caterpillars/Ekman, J, Tesoriero, L and Grigg, S (2014) ‘Pests, Diseases and Disorders of Brassica Vegetables: A Field Identification Guide’, Horticulture Australia Ltd, http://ahr.com.au/wp-content/uploads/2015/03/AHR_Brassica_Proof3.pdf
McDonald, G (2015) ‘PestNotes: Native budworm Helicoverpa punctigera’, Cesar and South Australian Research and Development Institute (SARDI), https://www.pir.sa.gov.au/__data/assets/pdf_file/0005/274181/Native_Budworm.pdf
Micic, S (2018) ‘Management and economic thresholds for native budworm’, Department of Primary Industries and Regional Development (DPIRD), https://www.agric.wa.gov.au/grains/management-and-economic-thresholds-native-budworm