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Insecticides Pest Engineering Part 12

Tham khảo tài liệu 'insecticides pest engineering part 12', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Pest Management Strategies for Potato Insect Pests in the Pacific Northwest of the United States 319 4.2.2 Damage This beetle can cause complete defoliation and nearly complete crop loss if allowed to reproduce unchecked. Both larvae and adults feed on potato foliage throughout the season. 4.2.3 Hosts Potatoes and other solanaceous plants such as eggplant nightshade horsenettle and buffalobur are preferred hosts of this pest. 4.2.4 Biology Pupation and overwintering occur in the soil. Adults emerge from the soil to lay eggs in the spring. Depending on the region this insect may have three generations in a season. Adult beetles spend the winter buried 10-25 cm in the soil and emerge in the spring just as the first volunteer potatoes appear. Recently emerged beetles either mate close to the overwintering sites or fly to new potato fields to find a mate. Usually first infestations occur around field margins. Eggs are deposited on potato foliage in masses. CPB eggs resemble lady beetle eggs. Larvae pass through four life stages and then burrow into the soil to pupate. 4.2.5 Monitoring Start monitoring fields at crop emergence. There are no established treatment thresholds for CPB. Large CPB populations are harder to manage than small ones thus the goal is to control this pest early in the season. 4.2.6 Control Crop rotation may help in delaying or reducing CPB pressure. Colonizing beetles need to feed before laying eggs so controlling volunteer potatoes and solanaceous weeds is important as are rotating crops and planting new potato fields far from the last year s potato fields Schreiber et al. 2010 . These practices will reduce the number of overwintering beetles migrating into the new field. This may not be a practical solution in the Pacific Northwest region since potatoes are use in rotation with other local crops such as wheat or corn. The use of at planting and systemic insecticides in early potatoes will contribute to the control of early-season CPB populations.