Pesticide Free Methods of Maize Weevil Control in Stored Maize for Developing Countries. Stored grain insect infestations rarely begin in the field. The life-cycles of the Rice and Maize weevils follow a similar course to that of the Grain weevil. Inspect at weekly intervals. Monitor crops after sowing until establishment. Uncontrolled they have been estimated to cost the country up to $280m per annum. Green vegetable bugs (GVB) are widespread but irregular pests of maize during summer. Knowledge of common maize crop pests can help smallholder farmers in early identification and control. These powders caused high mortality rates on the immature stages of the pests and repelled the adult weevils. Use press wheels at sowing. From a hectare of land, if all agronomic practices are done judiciously, a farmer should get at least 6tons of maize after harvesting. The head has a long slender snout. ... IA, USA: 2014. Control. The only way to control these pests is fumigation. Soil-dwelling insect pests can seriously reduce plant establishment, plant populations, plant growth, and subsequent yield potential, and should be monitored for prior to plating. Infestations can start in the field, but most damage occurs in storage. Maize Crop yields in many Kenyan farms have been reduced and destabilized by pests which also affect the quality of harvested produce. Most common during late summer, they suck sap and high populations (>15/plant) can transmit wallaby ear mycoplasma. Much of the maize produced in this sector is lost to weevil attack. Species found in Queensland include: Australian plague locusts, Migratory locusts, and Spur-throated locusts. Yellow peach moth is a minor and irregular pest of maize in Queensland. Female moths lay eggs on the stem, leaves (both sides) tassels, silks and husks on the upper two-thirds of plants. The maize weevil (Sitophilus zeamais), known in the United States as the greater rice weevil, is a species of beetle in the family Curculionidae.It can be found in numerous tropical areas around the world, and in the United States, and is a major pest of maize. The Australian Plague Locust Commission provides details of hopper migrations. Control. Infestationsdtected after crop emergence cannot be controlled. These weevils are a major pest of perennial ryegrass (Lolium perenne) in developed pastures, maize and cereal crops. Chapter 4: Effect of Storage Container Physical Disturbance on Maize Weevil Mortality. Redbanded shield bug is a widespread but minor summer/autumn pest that can be confused with green vegetable bug. The maize weevil is found in all warm and tropical parts of the world. Minor pests occur irregularly and will not be a problem every season. Bailey, CSIRO Publishing 2007. Found throughout the world, Maize Weevils are a pest which can be controlled like many other pantry pests. Sitophilus zeamais (maize weevil) is a field and storage pest of maize of economic importance in several parts of Africa. Whitegrub larvae (, spp., andPseudoheteronyx spp) feed on roots causing loss of vigour and lodging. Damage is worse when crop growth is retarded by dry, wet or cool conditions. No thresholds are available for mites in maize and control is not cost effective. Note: predatory earwigs are usually larger and light brown in colour. Insecticide seed dressings provide some protection. The best product to use in an integrated pest management system is a naturally occurring nucleopolyhedovirus (NPV). It varies from a dull red-brown to black, and is usually marked on the back with four light red to yellow spots. Leaf damage can indicate pest presence. Helicoverpa are usually not considered economical to control, except in high value seed maize. Damage is often patchy, and there are no effective controls, although a. Metarhiziumfungus and entomopathogenic nematodes have been reported to occasionally cause high larval mortality. Controlling of the pest by use of synthetic pesticides is raising serious concern on the environmental safety and consumer health hazards. Carbon dioxide at concentrations of 50 and 60%, respectively, killed all life stages of the weevil after 10 days of exposure. Hybrid varieties offer some resistance to wallaby ear. Rice and Maize Weevils are widely distributed in tropical and sub-tropical areas and will be carried to temperate areas on imported commodities. Adults and hoppers chew irregular pieces from leaves and stems and can cause complete defoliation overnight if populations are high enough. Assessment of infestations A variety of trapping techniques are available for measuring stored product beetle infestations. To detect, either hand sift 10 soil samples (30 x 30 cm) or place 10 germinating seed baits throughout the paddock. Equipment: Grain handling equipment should be kept clean. Silk damage reduces pollination and grain-set. Parallel rows of holes are signs of feeding on unopened leaves. As a guide, control is warranted if out of a count of 30 plants, 27 are infested, and more than 21 have at least 75% flag leaf loss. Feeding damage also occurs on the top 1-3 cm of the cob, and may result in the presence of mycotoxins. Older plants can outgrow damage but seed yield may be reduced. The main pests of maize are helicoverpa and a number of soil insects. Monitor during seedling and vegetative stages. 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