The adult weevil is a hard bodied compact beetle usually less than 3.5 mm long and 1.5 mm wide. The maize weevil has fully developed wings, and is a stronger flyer than the rice weevil, Sitophilus oryzae, and spreads more widely this way. 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. Adults may damage summer seedlings by chewing at or above ground level and replanting may be required. Avoid sowing new ground with maize after pasture in areas that have a known history of white grubs. 20. While these methods of pest control are equally essential, they have little in common with biological control or with each other outside the point that they may be integrated and used together (Ruberson et al., 1999). In-furrow sprays are not effective in protecting against dense populations. However, in temperate areas, post-harvest infestations are most common and originate from shipped-in grain or from already infested stored grains. Muir W.E., Yacuik G., Sinha R.N. Mechanisms of resistance in maize grain to the maize weevil and the larger grain borer. These powders caused high mortality rates on the immature stages of the pests and repelled the adult weevils. Pesticide Free Methods of Maize Weevil Control in Stored Maize for Developing Countries. This information is useful to personnel involved on agricultural research and development for developing location specific integrated pest management approach of this pest. Mites are usually present towards the end of the crop cycle during late summer/autumn and are favoured by hot, dry weather. Maize can be attacked by a wide range of insects. Sitophilus zeamais Motschulsky is the most important insect pest of stored maize in tropical regions. Young plants may be defoliated or killed. To detect, either hand sift 10 soil samples (30 x 30 cm) or place 10 germinating seed baits throughout the paddock. Severe damage to emerging crop can occur when large larvae are forced to move from weed hosts into the crop following spraying of the weeds. Leaf damage can indicate pest presence. Cultivation to a dept of 100 mm destroys overwintering pupae. Signs of damage include chewed leaf margins and faecal pellets at the base of young plants or in the throats of older plants. For chemical control and current registrations of these insects refer to Pest Genie or APVMA (Australian Pesticides and Veterinary Medical Authority). The Maize weevil will breed on maize in the field, but the Rice weevil only breeds in stored grain. Although chemical control may be cost effective, there are currently no threshold levels for GVB in maize. Note: predatory earwigs are usually larger and light brown in colour. October 25, 2017 at 1:02 pm Protecting stored grain from insect pests is essential for Africa’s future food security. There are no chemical controls available. Adults and hoppers chew irregular pieces from leaves and stems and can cause complete defoliation overnight if populations are high enough. Most develop from small numbers of pests already present in or around farm storage bins. Natural enemies provide little control. From the maize, maize-amaranth experiment, it was concluded that blending maize with amaranth during storage reduced maize weevil population growth by 46% compared to storing maize alone. Fine webbing on the lower leaf surface indicates their presence, and heavy infestations will result in leaf desiccation, leaf drop and yield loss. Emulsion concentrate can also be used such as Actellic EC. Rice and Maize Weevils are widely distributed in tropical and sub-tropical areas and will be carried to temperate areas on imported commodities. High numbers can cause plants to turn yellow and appear unthrifty. More detail on these pests can be found in Pests of field crops and pastures: identification and control edited by P.T. No thresholds are available for mites in maize and control is not cost effective. It is a pest of stored maize, dried cassava, yam, common sorghum and wheat. Feeding on secondary roots may cause the plants to fall over as they get larger. Species found in Queensland include: Australian plague locusts, Migratory locusts, and Spur-throated locusts. Spot treatments (e.g. Chemical control should target small caterpillars (up to 5 mm) and be directed at tassels and emerging silks. Locusts are sporadic and potentially major pests of maize. Larvae typically shelter in the soil during the day and curl into a ´C´ shape when disturbed. Parallel rows of holes are signs of feeding on unopened leaves. Insect resistant maize: recent advances and utilization. Resembles rice weevil, only bigger and the red-brown spots on wing covers are more clearly marked. These weevils are a major pest of perennial ryegrass (Lolium perenne) in developed pastures, maize and cereal crops. sanitary, cultural, botanical, biological and chemical control measures to manage weevil. The habit of mining into stems and cobs makes spray application ineffective as larvae are not exposed to insecticide. The head has a long slender snout. Also known as the Greater Rice Weevil. 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. Monitor during seedling and vegetative stages. Mycoplasma-infected plants are dark green colour with thickened veins on the underside of leaves. April 4, 2018. Maize Weevil Control Since 2002 A-Tex Pest Management has been fully licensed and insured to provide commercial businesses and residential homes of the Greater Austin, Texas area with professional services and expertise in pest control at an affordable price. Inspect emerging seedlings twice per week. The main pests of maize are helicoverpa and a number of soil insects. The incidence of damage is generally too low to warrant control. MAIZE WEEVIL BIOLOGY ^ weevil feeding corn seed The … Equipment: Grain handling equipment should be kept clean. Sitophilus zeamais (maize weevil) is a field and storage pest of maize of economic importance in several parts of Africa. It is grey-brown with three pale longitudinal stripes on its thorax. After harvesting, the grain needs to be dried to right moisture content of 12.5% (Wright, 1995) to avoid rotting in storage. What to Control. 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. Uncontrolled they have been estimated to cost the country up to $280m per annum. Queensland Government, Fraud, corruption and misconduct control policy, Economic recovery—support for Queensland producers announced, Back to work in agriculture incentive scheme, Agriculture research, development and extension (RD&E), Enhancing biosecurity capability and capacity in Queensland, Biosecurity policy, legislation and regulation, Eradicating varroa mites – the sweetest success, Workplace health management plans: COVID-safe farms, AgTech: Where agriculture meets technology, Food pilot plant: Making food dreams come true, Please contact us with your compliment or complaint. One larvae/germinating seed bait warrants control. Prepare ground for even and rapid germination. Female moths lay eggs on the stem, leaves (both sides) tassels, silks and husks on the upper two-thirds of plants. Insecticide application rates to protect stored cereal grain, except malting barley. Attacks from Attacks from Sitophillus oryzae can start in the field, when the moisture content is about 20% (although Sitophilus zeamais is the The effort involved in thorough preparation of storage bins is of little value if they are filled using contaminated equipment. Very little research has been done on the development of affordable organic pesticides which offer same control levels as synthetics to weevils. Recommended insecticides include Dust such as Actellic Dust. Partial damage to stems may cause the plant to wilt. Yield loss may occur on water stressed plants. Maize weevil is more likely than rice weevil to fly to a ripening crop in the field and establish an infestation in the grain before harvest. Wireworms generally favour moist areas. Conserve natural enemies through reduction of broad-spectrum insecticides against other pests as the disruption of natural enemies can flare mite outbreaks. Feeding damage also occurs on the top 1-3 cm of the cob, and may result in the presence of mycotoxins. Table 1. Adults and nymphs pierce and suck on lower leaf surfaces, causing yellowing on the upper leaf surfaces. They are similar in appearance to pink-spotted bollworm larvae. 2010. Bailey, CSIRO Publishing 2007. Chemical control options are generally not cost effective and the insecticides that control aphids may negatively impact natural enemies. Seed dressings, in-furrow sprays and granular insecticides offer some control. Grain Weevil Print page . Controlling of the pest by use of synthetic pesticides is raising serious concern on the environmental safety and consumer health hazards. Weed is one of the pests that reduce the yield of a maize farm. Since it is an internal pest, residual control will only kill; Exposed adults. Look for larvae under clods of soil, under vegetation and at the base of plants. IMPORTANCE AS A PEST: Grain weevils are important pests of farm-stored grain. Use press wheels at sowing. Adults and nymphs feed by piercing and sucking on developing cobs, and may severely deform cobs. There are two major ways to apply insecticides in order to control storage pests: By mixing the maize grain with the grain, the pest is killed when it gets in contact with the insecticide protected grains. The rice weevil has fully developed wings beneath its wing covers and can fly readily. Maize leafhoppers and maize thrips are widespread but irregular in Queensland, and can rapidly re-infest crops after spraying meaning more than one spray may be required. This enables us to improve your future experience on our website. Wasp parasitoids mummify and kill aphids. One larva per sample warrants control. In the light of the reorientation against synthetic insecticides, research that focuses on IPM that combines high varietal resistance and effective plant- or animal-derived insecticide is recommended for the control of maize weevil infestation in stored maize. Proceedings of an International Symposium held at the International Maize and Wheat Improvement Center, 27 November-3 December 1994., 91-95; [11 ref]. Cutworms may be found in any soil type and often move into the crop from adjoining fence lines, pastures or weedy fallows. Treat seedlings when there is a rapidly increasing area of infestation or proportion of crop damage (>10% seedling loss). Found throughout the world, Maize Weevils are a pest which can be controlled like many other pantry pests. Storage period 6 weeks - 3 months 3 months - 9 months Insecticide1 Mass emergence of adults occurs after rain in November-January, and damage is often worse when two host crops (e.g. Monitor crops after planting until establishment. Infestations are usually patchy. Previous studies had confirmed effectiveness of ground powder derived from these plants in control of maize weevil in western Kenya (Ogendo et al., 2004a, Ogendo et al., 2004b). Control. Older plants can outgrow damage but seed yield may be reduced. Treat older plants if more than 90% of plants are infested or more than 50% of plants have 75% or more leaf tissue loss. Larvae tunnel into stems or cobs producing masses of webbing and excreta at the tunnel entrance. Assessment of infestations A variety of trapping techniques are available for measuring stored product beetle infestations. True wireworm larvae bore into germinating seed and chew on seedling roots and shoots resulting in reduced vigour, wilting or seedling death. For more information, visit the NPV page . Cereal grains include: barley, maize, millets, oats, rice, sorghum5, triticale, wheat. The use of phytochemicals for controlling storage pests constitutes an attractive alternative to synthetic products, … Whitegrub larvae (, spp., andPseudoheteronyx spp) feed on roots causing loss of vigour and lodging. Use germinating seed baits or soil sampling to detect larvae prior to sowing. Knowledge of common maize crop pests can help smallholder farmers in early identification and control. This is quite laudable; but maize farmers face lots of problems, chiefly pest. For general information about soil insects and germinating seed baits (GSB) see How to monitor for and recognise soil insects . Two-spotted mite is a widespread but irregular pest of maize during seed fill to maturity. False wireworm larvae attack germinating seeds and seedling roots and shoots in spring, resulting in patchy stands. Leaf beetles are an irregular pest of maize: Armyworms can occur in large numbers especially when good rain follows a dry period. As larvae are most active at night, spraying in the afternoon or evening may produce the best results. Shallow planting in warm moist soil will encourage rapid crop emergence and growth, thus reducing the impact of insects. The rice weevil is a small snout beetle which varies in size, but it averages about three thirty-seconds inch in length. Control of rice weevil (Sitophilus oryza L., Coleoptera: Curculionidae) with various formulations of Metarhizium anisopliae. Both adults and larvaefeed on internally on maize grains and an infestation can start in the field (when the cob is still on the plant) but most damage occurs in storage. Predators include green carab beetles, predatory shield bugs and perhaps common brown earwigs. Corn aphid is the most common aphid species on maize and can affect any crop stage. Minor pests occur irregularly and will not be a problem every season. Carbon dioxide at concentrations of 50 and 60%, respectively, killed all life stages of the weevil after 10 days of exposure. The maize weevil is found in all warm and tropical parts of the world. Keep fallows clean and eliminate weeds from paddock perimeters for at least one month before planting. Black field earwig is a sporadic and potentially major pest of maize, black earwigs eat newly sown and germinating seed and the roots of crops resulting in poor establishment. During the day the common armyworm shelters in the throats of plants or in the soil and emerge after sunset to feed. Grain baits containing insecticide applied at sowing offer best protection. Crop Protection 23: 103-108. Weeds are unwanted crops that grow sporadically with the sown crop. Stored grain insect infestations rarely begin in the field. The predominant control of this pest is the use of synthetic residual pesticides, which have adverse effects on consumers and environment. It is a stronger flier than the rice weevil. Redbanded shield bug is a widespread but minor summer/autumn pest that can be confused with green vegetable bug. Predators of aphids include ladybird larvae, damsel bugs, bigeyed bugs, larvae of green lacewings and larvae of hoverflies. Helicoverpa are usually not considered economical to control, except in high value seed maize. SA scientist’s maize weevil control breakthrough. Chaisaeng, P., Chongrattanameteekul, W., Visarathanonth, P. and Vajarasathiara, B. The Australian Plague Locust Commission provides details of hopper migrations. The maize weevil breeds on maize in the field but the Rice weevil only breeds in stored grain. Impact. From a hectare of land, if all agronomic practices are done judiciously, a farmer should get at least 6tons of maize after harvesting. control of this pest is the use of synthetic residual pesticides, which have adverse effects on consumers and envi-ronment. Pesticide free methods of maize weevil control in stored maize for developing countries Denis Bbosa Iowa State University Follow this and additional works at:https://lib.dr.iastate.edu/etd Part of theAgriculture Commons, and theBioresource and Agricultural Engineering Commons This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and … Infestations can start in the field, but most damage occurs in storage. Inspect at weekly intervals. Privacy Statement, Privacy Statement - Bayer Environmental Science Australia, Australian Terms and Conditions of Purchasing. Santos et al (1999) described the use of a carbon dioxide controlled atmosphere in Brazil for the control of S. zeamais on maize and wheat. Commonly, loss of weight is up to 5%, but severe infestations increase the losses up to 40%. Soil baiting may reduce damage by black field earwigs and crickets that attack the tips of developing prop-roots (secondary roots). maize, peanuts, chickpea, lucerne) are grown in sequence. An effective sanitation program can eliminate or greatly reduce the chance of having serious problems with these insects. Armyworm larvae are attacked by a number of parasitoids that may assist in reducing the intensity of outbreaks, although are unlikely to give timely control if armyworm numbers are high. Hybrid varieties offer some resistance to wallaby ear. Insecticide seed dressings provide some protection. Initial infestations can be patchy. For adults, use cracked grain baits.
Silk damage reduces pollination and grain-set. Chapter 4: Effect of Storage Container Physical Disturbance on Maize Weevil Mortality. Crop areas attacked by cutworms tend to be patchy and the highest risk period is during summer and spring. The use of phytochemicals for controlling storage pests constitutes an attractive alternative to synthetic products, since plant may be more biodegradable and safer. Many chemicals will control armyworms but their effectiveness is often dependent on good penetration and control may be more difficult in high-yielding thick canopy crops, particularly when larvae are resting under leaf litter at the base of plants. It varies from a dull red-brown to black, and is usually marked on the back with four light red to yellow spots. Serious damage is usually confined to soils that retain moisture well, and earwigs prefer cultivated soils to undisturbed soil (zero till). Grain Weevil. 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