Nymphs are light green, darkening to bluish or olive green adults, with black antennae and legs, and purple areas at the base of the two upright, backward-pointing tubes ("cornicles") at the rear of the body (Photo 2). 2011, Hodgson et al. 2004, Ragsdale et al. The main pests of maize are helicoverpa and a number of soil insects. Management. Seed treatments help deter feeding. False wireworm larvae attack germinating seeds and seedling roots and shoots in spring, resulting in patchy stands. Adults may feed on leaves. Maize varieties with husks extending 50-80 mm beyond the top of the cob and closing tightly around the silks restrict the entry of larvae into the cob. One of the most important requirements for growing corn is a high quality soil which is deep, fertile and well-draining with a pH between 6.0 and 6.8. The Maize aphid - Rhopalosiphum maidis (Fitch) can be a minor pest of Barley, Maize, Sorghum, Tef and Wheat. Minor pests occur irregularly and will not be a problem every season. plants Article Impact of Fungal Endophyte Colonization of Maize (Zea mays L.) on Induced Resistance to Thrips- and Aphid-Transmitted Viruses Simon Kiarie 1,2, Johnson O. Nyasani 2,3, Linnet S. Gohole 1, Nguya K. Maniania 2 and Sevgan Subramanian 2,* 1 Department of Seed, Crop and Horticultural Sciences, University of Eldoret, 30100 Eldoret, Kenya; firstname.lastname@example.org (S.K. maize, peanuts, chickpea, lucerne) are grown in sequence. The best product to use in an integrated pest management system is a naturally occurring nucleopolyhedovirus (NPV). Damage symptoms. Corn leaf aphids are blue-green in color and trimmed in black. Although chemical control may be cost effective, there are currently no threshold levels for GVB in maize. For aphid transmission assays, a virus-free colony of R. maidis was reared on detached leaves from healthy plants of maize (Zea mays L.) in a growth chamber under 25 ± 1 °C and a photoperiod of 14 L:10D h. Corn root aphid: The aphids pierce plant roots and cause retarded growth. Intercropping beans with maize is a common practice in East Africa. Plant-derived products, such as neem, derris, pyrethrum and chilli (with the addition of soap). 2004, Wu et al. Other species of Aphelinus have been used elsewhere with equally beneficial results, as well as the braconids, Lysiphlebus species. Viral and fungal diseases are recorded as causing mortality of armyworms. NATURAL ENEMIES Aphid populations are controlled by environmental factors, several parasitic wasps, fungal diseases, ladybird beetles, syrphid fly larvae, and lacewing larvae and adults. Insecticide seed dressings provide some protection. Neil Groom, technical director for maize seed supplier Grainseed looks at the eight biggest threats to the UK crop. Aphid numbers on maize increased over the six-week period from a mean of 91.2 to 1383.5 and on wheat from a mean of 27.3 in week 18 to 117.7 in week 21. craccivora density increased over time in the peanut monoculture and intercropping systems before 10-Jul (F 8, 315 = 92.33, P < 0.0001), and intercropping significantly lowered aphid densities (F 1, 315 = 35.21, P < 0.0001). Spray the base of attacked plants with a contact (or) systemic insecticide like dimethoate 30 EC or methyl demeton 25 EC 500 ml in 500 L of water; 7. Overall, maize had the highest mean number of nymphs and apterous adults (530.7) recorded on leaves, … Hence, this document aimed to provide comprehensive integrated pest management practices to reduce crop losses caused by diseases and insect pests of maize. Collect, burn or bury the remains of crops after harvest. Feeding by this aphid causes yellow mottling, but this damage is seldom of economic importance. Note: predatory earwigs are usually larger and light brown in colour. For more information, visit the NPV page . Sooty mould fungi develop on honeydew discharged by the aphids that falls onto the leaves. Maize aphid Armyworm Banded blister beetle 8. Spray monocrotophos 36 SL (or) endosulfan 35 EC 1 l /ha. Pest Management and Economic Zoology, 12(1):65-70. Colonies of aphids are seen in central leaf whorl, stems, or in panicles. Monitor during seedling and vegetative stages. Maize can be attacked by a wide range of insects. It has approxi… and intercrop did not reduce aphid infestation/cowpea damage levels in all the seasons. More detail on these pests can be found in Pests of field crops and pastures: identification and control edited by P.T. Mites are usually present towards the end of the crop cycle during late summer/autumn and are favoured by hot, dry weather. Neil Groom, technical director for maize seed supplier Grainseed looks at Corn Aphids Scientific names: Corn leaf aphid: Rhopalosiphum maidis Greenbug: Schizaphis graminum Green peach aphid: Myzus persicae (Reviewed 1/06, updated 8/08, corrected 3/19) . 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. The common aphid species in maize fields include R. padi, R. maidis, M. miscanthi and other wheat aphids. There are no chemical controls available. Maize leafhoppers and maize thrips are widespread but irregular in Queensland, and can rapidly reops‐infest cr after spraying meaning more than one spray may be required. 2. Integrated MDMV control management should comprise three basic measures: destruction of Johnsongrass plus other wild hosts (the source of MDMV under field conditions); control of aphid vectors; and breeding of resistant maize and sorghum genotypes (Milinko et al., 1979; Gorbunova et … Note that helicoverpa larvae may be confused with armyworms or cutworms. The honeydew can become moldy, giving the tops of the plants a black, sooty appearance. Cutworms are attacked by a range of natural enemies such as parasitoids, predators and diseases. Corn leaf aphids are blue-green in color and trimmed in black. cultivated paddocks). Treat older plants if more than 90% of plants are infested or more than 50% of plants have 75% or more leaf tissue loss. Look for honeydew on leaves, tassels, and cobs. Particularly during dry/periods the colonies appear on the inflorescences and young leaves. Adults and hoppers chew irregular pieces from leaves and stems and can cause complete defoliation overnight if populations are high enough. 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. • The linear regression analysis indicated that peanut/maize strip intercropping could achieve in … Look for ants that are attracted to the aphids' honeydew. Vegetable oil (1 cup cooking oil; 2 cups water; 1 teaspoon dishwashing liquid. Maize aphid : Attacks are on leaves as a black fungal growth (called sooty mold) often occurs on the honeydew secreted by aphids. Sharma HC; Ashok Bhatnagar, 2004. Look for colonies in the wholes of leaves at the top of the maize. cultural and chemicl control measures for effective and low cost management of maize pests. The aphid is one of the most economically damaging pest on maize. IPM in Maize • Cultural Practices • Deep summer ploughing followed by fallowing helps in exposing resting stage of pests. Use of pesticides in intercrop leads to health and environmental risks. Adults and nymphs suck sap and produce honeydew. Management. This fact sheet is a part of the app Pacific Pests and Pathogens. It is recorded from Australia, Cook Islands, Fiji, New Caledonia, New Zealand, Northern Marianna Islands. Aphids are often found under curled leaves, where they hide from their natural predators. The combined action of natural enemies (including predators of eggs, larvae and pupae, parasites of eggs and larvae, and caterpillar diseases) can have a significant impact. In conclusion, although Cry1Ab concentrations in maize leaves increased as the plants developed, Cry1Ab levels were significantly reduced in the aphid R. maidis, and no traces of Cry1Ab were detected in P. japonica preying on Bt maize-fed aphids. Predators of aphids include ladybird larvae, damsel bugs, bigeyed bugs, larvae of green lacewings and larvae of hoverflies. biosynthesis genes in maize-aphid interactions. All viruses used in this study were isolated from field-collected maize samples either by mechanical inoculation or by aphid transmission. along field edges) may be successful. Larvae typically shelter in the soil during the day and curl into a ´C´ shape when disturbed. Feeding by this aphid causes yellow mottling, but this damage is seldom of economic importance. on wheat. The main pests of maize are helicoverpa and a number of soil insects. Figure 1. 2012). For instance, leaving or growing flowering plants at the boarder of the crops or as companion plants within the crops attracts beneficial insects. WEED MANAGEMENT IN MAIZE. In tropical, subtropical and temperate regions. 70 71. ... Corn aphid is the most common aphid species on maize and can affect any crop stage. In eastern Africa, Maize lethal necrosis (MLN) is caused by the co-infection of maize plants with Maize chlorotic mottle virus (MCMV) (Tombusviridae: Machlomovirus) and Sugarcane mosaic virus (SCMV) (Potyviridae: Potyvirus). 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.
Signs of damage include chewed leaf margins and faecal pellets at the base of young plants or in the throats of older plants. maize area, the productivity can only be raised by providing seed of improved cultivars, better agronomic practices and protection against diseases and pests. Although aphid species are difficult to distinguish from one another, management is similar for most. Maize is in the tribe, Maydeae, which includes the dent corn (the subject of this chapter), flint corn, sweet corn, and popcorn. MANAGEMENT Many commercial corn hybrids are highly tolerant of the disease and no control is needed; control aphid populations on plants and remove any Johnson grass growing in the vicinity as … Adults and nymphs feed by piercing and sucking on developing cobs, causing deformities, similar to green vegetable bug damage. Corn aphid Corn aphid (Rhopalosiphum maidis) is the most common aphid species on maize and can affect any crop stage. Adults and nymphs pierce and suck on lower leaf surfaces, causing yellowing on the upper leaf surfaces. Get identification tips and learn more about the corn leaf aphid’s natural enemies, its potential impact on crop and management considerations. Therefore, for effective management of maize lethal Sugarcane mosaic virus necrosis disease, management of aphid vectors is critical. In-furrow spraying helps protect young roots and shoots. Resistant varieties of maize and barley are known too; these have leaf compounds which have a defensive role against the aphid. Scientific name: Rhopalosiphum maidis. Fine webbing on the lower leaf surface indicates their presence, and heavy infestations will result in leaf desiccation, leaf drop and yield loss. Species found in Queensland include: Australian plague locusts, Migratory locusts, and Spur-throated locusts. Scouting for either aphid species should start before tasseling - probably too late for that this year. Department of Agronomy Institute of Agriculture and Animal Science Tribhuwan University Nepal INTRODUCTION Maize (Zea mays L.) is the second most important cereal crop in the world in terms of total food production. Some aphids have wings, but they are not strong fliers, and are more likely to be blown in the wind onto new crops. Management • Scraping field bunds and summer ploughings to destroy eggs, dusting cabaryl 10D or malathion 5D @ 10 kg/ac or foliar spraying with fenitrothion 2 ml/l found effective in their management. Among them, R. maidis and R. padi have the most Bio-efficacy of different insecticides against corn leaf aphid Rhopalosiphum maidis (Fitch.) Host range- Sorghum, Maize, Ragi. Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), continues to be the most significant insect pest of soybean, Glycine max (L.) Merr., in the Upper Midwest of the United States (Hurley and Mitchell 2017).The biology, impacts, and management of soybean aphid have been well reviewed (Ragsdale et al. Cultivation to a dept of 100 mm destroys overwintering pupae. Of the many wasps that attack the maize aphid, Aphelinus maidis is common in Hawaii and populations are controlled by this introduced parasitoid. Spray when caterpillars are feeding (dusk-night). Dilute the mixture at 3 teaspoons per half litre of water and spray on the infested leaves). Yield loss may occur on water stressed plants. Parallel rows of holes are signs of feeding on unopened leaves. However, insecticides are considered essential for management of aphid Wasp parasitoids mummify and kill aphids. Adults and nymphs suck sap and produce honeydew. Redbanded shield bug is a widespread but minor summer/autumn pest that can be confused with green vegetable bug. Caterpillars hatching prior to silking cause little damage to tassels but may cause damage when migrating to cobs. Without ants, predators and parasites will bring about natural control. There are at least 4,000 aphid species, and almost every plant will attract aphid pests. The… Maize, Zea mays, is an annual grass in the family Poaceae and is a staple food crop grown all over the world.The maize plant possesses a simple stem of nodes and internodes. 2004, Ragsdale et al. Botanically, maize is a grass of the family Gramineae which includes other common crops such as wheat, oats, barley, rye, rice, sorghum, and sugarcane. A, PLS-DA plots of 1,607 genes identified by transcript profiling of inbred line B73 infested with aphids for the indicated time periods.Ovals indicate 95% confidence intervals. Cutworm larvae feed on leaves and stems of young plants, and ´cut´ down plants to eat the leaves. Press wheels can reduce damage from false wireworm larvae and earwigs by encouraging plant emergence and firming the soil to reduce insects´ ability to move through it. Do not plant down-wind from crops with aphids. Maize aphid infested resulting in a yield loss of 0.876% in bean, sorghum, barley, cotton and mustard (Alam et al., 2015a, b, c). Insect pest management in maize. Discipline: Insect pest Additional keywords: aphid, armyworm, bird, oriental com borer, wireworm Introduction Maize is cultivated in paddy and upland fields throughout the … Use germinating seed baits and control if more than 50 earwigs in 20 germinating seed baits. Large numbers of aphids occur on maize "tassels" (the male flowers) preventing the development of pollen (Photo 1). Initial infestations can be patchy. Maize can be attacked by a wide range of insects. Corn plants are very heavy feeders and even the most fertile of soils may need to supplemented with nutrients as the plants develop, particularly nitrogen. PEST MANAGEMENT DECISION GUIDE: GREEN LIST . Damage Major insect pests of maize and their management There are four major pests of maize prevalent in India. Biotic Constraints Nymphs become adults within 7-14 days, depending on temperatures. Synthetic pyrethroids are likely to be effective, but will also kill natural enemies. Particularly during dry/periods the colonies appear on the inflorescences and young leaves. Yellow peach moth is a minor and irregular pest of maize in Queensland. It is grown for fodder as well as for grain. Pests, weeds and disease in maize crops can severely reduce yield and quality. Pests, weeds and disease in maize crops can severely reduce yield and quality. The aphid produces an abundance of honeydew on which molds grow. Management. Other aphid species can also be found, including greenbug and English grain aphid, but are not as common in corn this year. Feeding on secondary roots may cause the plants to fall over as they get larger. Scientific name: Peregrinus maidis. Prepare ground for even and rapid germination. Photo by David Cappaert, www.ipmimages.org Partial damage to stems may cause the plant to wilt. The Australian Plague Locust Commission provides details of hopper migrations. NATURAL ENEMIESAphid populations are controlled by environmental factors, several parasitic wasps, fungal diseases, ladybird beetles, syrphid fly larvae, and lacewing larvae and adults. Scouting for either aphid species should start before tasseling - probably too late for that this year. Monitor crops after sowing until establishment. The habit of mining into stems and cobs makes spray application ineffective as larvae are not exposed to insecticide. Feeding damage also occurs on the top 1-3 cm of the cob, and may result in the presence of mycotoxins. Conserve natural enemies through reduction of broad-spectrum insecticides against other pests as the disruption of natural enemies can flare mite outbreaks. Chemical control should target small caterpillars (up to 5 mm) and be directed at tassels and emerging silks. Aphid numbers on maize increased over the six-week period from a mean of 91.2 to 1383.5 and on wheat from a mean of 27.3 in week 18 to 117.7 in week 21. Photo 3. For chemical control and current registrations of these insects refer to Pest Genie or APVMA (Australian Pesticides and Veterinary Medical Authority). Maize stem borer, Chilo partellus (Lepidoptera: Pyralidae) • Most destructive pests of maize and sorghum. For general information about soil insects and germinating seed baits (GSB) see How to monitor for and recognise soil insects . For adults, use cracked grain baits. One larva per sample warrants control. Spray the underside of leaves, as the soap and oils must contact the aphids. In many countries, ants protect them from predators and parasitoids. Introduction Transgenic Bacillus thuringiensis Berliner (Bt) maize hybrids that encode insecticidal proteins provide protection against certain lepidopteran or coleopteran pests (Svobodová et al., 2017 ). Grain baits containing insecticide applied at sowing offer best protection. Scouting of corn plots should be initiated when tassels emerge. Percentage of maize infected by barley yellow dwarf virus (BYDV) was also recorded over three years. Maize was given the scientific name, Zea mays L. by Linnaeus. Rice root aphid is a cosmopolitan species (Blackman and Eastop 2000, Hesler and Kindler 2007) with North American collections dating to 1900 (Doncaster 1956). Watering during dry weather prevents the husks from loosening. Crop management practices for the safe use of salt-affected soils and saline water primarily consists of growing suitable salt-tolerant crops, managing seedbeds, and grading fields to minimize local accumulation of salts, soil management, improving irrigation efficiency and soil, water, and salinity monitoring for assessing leaching and drainage requirements. Use of press wheels at planting provides some control. Worldwide. Aphids suck the sap of plants, often occurring in large numbers, causing plants to yellow and wilt. ... Corn aphid is the most common aphid species on maize and can affect any crop stage. • Its caterpillar damage maize and sorghum by boring into the stems, cobs or ear. This is to ensure that we give you the best experience possible. All parts of the maize plant are subject to injury, although aphid infestation produces the greatest damage in the tassel, causing varying degrees of barrenness. High numbers can cause plants to turn yellow and appear unthrifty. Heavily infected seedlings rarely grow taller than 25 cm. Examine the ear, leaves and stalk. Management. Soil baiting may reduce damage by black field earwigs and crickets that attack the tips of developing prop-roots (secondary roots). Silk damage reduces pollination and grain-set. Green vegetable bugs (GVB) are widespread but irregular pests of maize during summer. Bird cherry oat aphid is green with an orange saddle between the cornicles. The aphid spreads many viruses, e.g., Sugarcane mosaic virus, which infects both sugarcane and maize, and it is a major vector of Barley yellow dwarf virus, one of the most important diseases of cereals. Management. Examine the ear, leaves and stalk. Crop areas attacked by cutworms tend to be patchy and the highest risk period is during summer and spring. Corn also requires ample space as it grows large in size and is pollinated by wind. The caterpillar causes damage by constructing webs on maize cobs and feeding on the flowers and grains. Young plants may be defoliated or killed. 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. Maize aphid (Ropalosiphum ... Habitat management. Home-made preparations are ideal for small numbers of plants, but commercial products are probably the only practical solution when crop areas are large. Spread also occurs in wind currents. Chemical control options are generally not cost effective and the insecticides that control aphids may negatively impact natural enemies. Maize crops often have high levels of beneficial insects (predators and parasitoids) that may be harmed by insecticide applications. The most important tools for aphid management are natural enemies that prey on aphids, such as lady beetles, lacewings, syrphid flies, soldier beetles and small parasitic wasps. Fungal-based biopesticides offer a better option because they are environment- and consumer-friendly. Cite This Article: Spot treatments (e.g. 2011, Tilmon et al. There are a number of commercially formulated NPV products on the market for the control of helicoverpa. I… • Its caterpillar damage maize and sorghum by boring into the stems, cobs or ear. 09 Feb 2018, © The State of Queensland (Department of Agriculture and Fisheries) 2010–2020. For all three aphid species there was a good correlation between weekly counts on maize and corresponding suction trapping of alates. Cowpea aphid, Aphis craccivora, is a major cowpea pest. AUTHOR Grahame JacksonInformation from CABI (2015) Rhopalosiphum maidis (green corn aphid) Crop Protection Compendium (www.cabi.org/cpc); and Rhopalosiphum maidis (Fitch) (1992) Crop Knowledge Master Department of Entomology, Honolulu, Hawaii (http://www.extento.hawaii.edu/kbase/crop/type/rhopalos.htm). 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