Insect pest risk
|High risk||Moderate risk||Low risk|
|Compensation for early helicoverpa damage is reduced in water stressed crops, and in late crops running into cooler autumn weather.|
|Crops in more inland regions (Downs, Emerald) in high rainfall years.|
|Risk higher in warm summers with frequent north west winds.||Mirid activity much lower in cool summers.|
|Spring crops planted close to winter cereals.|
|Two spotted mites|
|Crops close to poorly managed early maturing crops with a history of mites (e.g. cotton).||Use of non-selective pesticides (especially synthetic pyrethroids) in vegetative stages may flare mites.|
|Planting spring crops close to winter cereals increases the risk of cereal thrips.|
|Bean pod borer||Damaging||Damaging||Damaging|
|Present||Present in crop but generally not damaging|
|Damaging||Crop susceptible to damage and loss|
Key IPM strategies for mungbeans
- Mungbeans are most susceptible to pests from budding onwards.
- Vegetative mungbeans can tolerate up to 33% defoliation without yield loss. Tolerable defoliation drops to 15-20% once flowering and podding commences.
- At flowering, under good growing conditions, mungbeans can compensate for moderate levels of early damage by setting new buds to replace those damaged by pests. Excessive early damage leads to uneven pod ripening and delayed harvest.
- Stressed crops are less able to compensate for pest damage.
- Shorten the crop flowering period by planting on full moisture profile and water crops just before budding
- The addition of a salt (NaCl) adjuvant to some chemicals at reduced rates (targeting mirids, pod sucking bugs and aphids) can still provide good efficacy on pests while reducing the impact on beneficials, but may also reduce residual effectiveness.
- H.armigera is resistant to synthetic pyrthroids (SPs) and has previous carbamate resistance issues.
- Redbanded shield bug is resistant to SPs. The addition of a 0.5% salt adjuvant to deltamethrin-based pesticides achieves up to 60% control.
- Bean podborer is resistant to synthetic pyrethroids – consider using a product other than a SP.
- Smudge bugs, important aphid predators, are also resistant to SPs.