Remember that larvae need to be present and not already bored into the stalk for insecticides to be effective. The pest has been also observed at an ERI>0.70.8, in which regions B. fusca enters into diapause to overcome unsuitable conditions.
Busseola fusca exhibits oligophagous feeding behavior on host plants belonging to the family Poaceae. The idea is that the herbicide will kill the grass and force larvae to move, and they will be killed by the residual insecticide. In cases where stalk borers begin feeding on grassy weeds or other vegetation in field edges, control is most effective if timed between 1,400 and 1,700 degree days (base 41F), which corresponds to the first half of the period when stalk borers are migrating from weedy hosts into corn. It is a commodity which forms a large part of our economy which is why we need to look after it carefully. Recent studies in Kenya indicated that more than 10% of potential maize harvest is lost due to infestation by B. fusca in highland tropics, moist transitional zones, and moist mid-altitude zones. Cultural practices. Young plants have a lower threshold because they are more easily killed by stalk borer larvae. Determine the need for treatment when 1,400-1,700 DD have accumulated. Rainwater dissolves the active substances in neem powder as it gathers in the funnel and washes out the powder. Maize plants are less tolerant to stemborer attack than are sorghum and pearl millet, and hence losses of maize grain yields are greater. Photo 1. Fields must be inspected twice a week. Haile, T. Kauma Matama, et al. Chemical control can be achieved by applications of granules or dust into the leaf whorl at early crop growth to kill early larval instars. Yield losses attributed to stalk borers areas high as about 40%. The pupal stage lasts approximately 3 weeks (range 16-40 days). Early slashing of maize stubble and laying it out on the ground where the suns heat destroys the larvae and pupae within can also be done. Eggs laid on grassy-type weeds in the field are usually destroyed by tillage. Le Ru, N. Mujica, & P. Carhuapoma, Maize stalk borer, African maize stalk borer, sorghum stalk borer (English), Perceur de la tige du mas (French), Maisstengelbohrer (German). Wear gloves, a face mask and protective glasses when dealing with any chemical. Stalk borers are an occasional pest of corn in Nebraska. Check corn plants bordering grassy areas to determine the percentage of plants with stalk borer injury when 1,300-1,400 degree days (41F base) have accumulated since Jan. 1 (Figure 3). In this country, we rely on maize as our staple diet. Scout corn near field edges or former weedy areas for damaged corn. The eggs hatch in May and the larvae bore into the stems of nearby weeds or crop plants. Diversity of lepidopteran stem borers on monocotyledonous plants in eastern Africa and the islands of Madagascar and Zanzibar revisited. In reduced tillage or weedy situations, treatment may be advisable if the cover crop or weeds in the field are infested prior to planting. West Africa (at sea level to altitudes of 2,000 masl): Benin, Burkina Faso, Cameroon, Ghana, Guinea, Ivory Coast, Mali, Nigeria, Sierra Leone. However, timing of such treatments are critical to increase the probability of success. More eggs are laid on the trap plant than on the crop, but the larvae develop poorly or not at all on the trap plant. They attack many species of crop and weed plants. Chemical control. Silvain. The most destructive stage of the insect is the larval stage. One method that can assist in determining time of sampling for stalk borer is a degree day accumulation model developed by Iowa State University. Eggs are 0.81 mm in diameter and are creamy-white when laid but darken just before emergence (Photo 2A). Stalk borer injury to soybean. Using a base threshold of 41 F (5 C) from January 1, egg hatch and initial infestation will take place around 600 degree days. Beauv.) 4B). Le Ru, S. Dupas, P. Moyal, P.A. 2150 Beardshear Hall B. fusca also occurs in South Africa, with an ERI>0.70.8; this might be due to diapausing last instar larvae during the southern winter (diapause in insect life cycles cannot be considered in Insect Life Cycle Modeling because factors responsible for the diapause are unknown).
The percentage mortality of eggs, larvae, and pupae decreased at temperatures of 1525C and increased thereafter. Silvain. If the plant survives, the later stages of the larva will bore into the stem and feed on the meristematic tissue of the stem. Control of grassy weeds is important to keep stalk borer problems from increasing year to year. Mally, C.W. Most of these countries have the Plant Protection Act that offers guidelines on actions to be taken to eradicate, reduce, or prevent the spread of such pests. Use plant protection products safely. If plants survive, they will likely grow tillers and be stunted. This is a big help to the farmer in controlling pests. Photo 4. Photo 6. 42: 471479. . Larvae bore into the stalks of grasses or other hosts such as ragweed and begin feeding. Haile, T. Kauma Matama, et al. These irregular rows of holes will be much larger and more ragged than those caused by whorl-feeding of first generation European corn borer larvae. Parasitoids also cause a small percentage of mortality. The front wings and the body are usually dark brown; lighter-colored specimens are not uncommon (Photo 2D, E). Examine several sets of 10 plants. The maize stalk borer, Busseola fusca Fuller. B. fusca is native to sub-Saharan Africa (SSA) and is not known to occur anywhere outside the African continent (Fig. 2005a. Le Ru, B.P., G.O. The grey moth is the male and the white moth is the female. The adult wingspan measures about 2540 mm. In South Africa, B. fusca infestation results in yield losses of 10100%. The annual population growth potential varies AI>36 (Fig. Look for feeding damage and larvae that are still in the whorl. and molasses grass (Melinis minutiflora P. Adults mate soon after emergence. 2006. However, they help control to reduce pest densities as part of an integrated pest management approach that includes habitat management practices that conserve parasitoids and predators like ants and earwigs. Head is medium brown, and a prothoracic shield usually paler than head; pinnacula brown, caudal plate matching prothoracic shield in color. She is a professor with extension and research responsibilities in corn and soybeans. Grassy-type plants or weeds in the field, waterways, or fence rows are typical oviposition sites. Stalk borer (Papaipema nebris) is an occasional pest of corn in Iowa, but some fields experience persistent stalk borer issues. They may feed on soybeans as well, but they are not an economically important pest of soybeans. Seed damage. In conventional tillage, stalk borer damage is usually confined to field margins and corn plants along grassy waterways and terraces. 6). Damage caused by feeding in the whorl will first appear as irregular rows of holes in the unfolding leaves. Adult stalk borer moth. Control of populations moving into a field from field borders is also possible with a broadcast treatment along the edge of the field and in infested areas within a field. Record the number of plants infested and determine the location of the worms, such as in the whorl, stalk, etc.
Management targeted while stalk borers are active (planting to July) will force them to move to nearby crops earlier. Although never recorded outside of SSA, B. fusca has a high potential of establishment in most tropical areas of North, Central, and South America as well as Southeast Asia. 1976. Use the Pest Forecasting Maps to track GDD for stalk borer. Heavy feeding can lead to abnormal plant growth, such as twisted leaves. Finding dead heads in nearby grasses or weeds is an indicator of stalk borers in the area. When larvae feed on seeds in the cob, frass deposits are visible (Photo 1E, F). Young corn is particularly vulnerable to severe injury; plants are unlikely to be killed once they reach V7. The use of an economic threshold, first developed by Iowa State University entomologist Larry Pedigo, will help determine justifiable insecticide treatments based on market value and plant stage (Table 1). Sometimes, larvae burrow into the stalk at the base of the plant and tunnel upward. The older larvae tunnel in the stem. Infested parts facilitate infection by other pathogens like fungi.
Entomology Memoir 40, Department of Agricultural Technical Services, Republic of South Africa 24pp. The larva is easily recognized by the prominent longitudinal white stripes on the anterior and posterior ends. ADAPTATION OF INTEGRATED PEST MANAGEMENT TO FUTURE PEST RISKS, http://keys.lucidcentral.org/keys/v3/eafrinet/maize_pests/key/maize_pests/Media/Html/Busseola_fusca_(Fuller_1901)_-_African_Maize_Stalkborer.htm, 7.4.2 Apenteles subandinus (Canedo et al.). Journal of Economic Entomology 101(1): 9098. Many natural enemies of the African maize stalk borer have been reported, but their impact is variable across regions, seasons, and crops. For more information on stalk borer biology and management, read a Journal of Integrated Pest Management article by Rice and Davis (2010), called Stalk borer ecology and IPM in corn. This publication contains many photos of stalk borer injury in corn and soybean and is a good reference guide. Purdue University is an equal access/equal opportunity university. Updated degree day data are available at https://mesonet.unl.edu/page/data. Corn and Soybean Insecticide Evaluations 2008. 2005b. They locate the stemborers inside of plant stems and lay eggs into them. Figure 2. In severe cases an infested plant will have a very ragged appearance, with abnormal growth habits such as twisting, bending over, or stunting. Host-plant parts affected are leaves, stems, and cobs (maize) as well as inflorescences of maize, sorghum, millet, and wild grasses. Corn plants attacked by this insect will show round to irregular shaped rows of holes through the unfolded leaves which may become tattered with time. 6). . A variety of foliar insecticides are effective against common stalk borers in corn.
In older plants caterpillars bore into stems and cobs. The predictions for 2050 indicate a decrease in the establishment potential of B. fusca in most lowland areas of West, East, and Central Africa, as well as outside its current range of distribution in Asia (e.g., India). Annals of Applied Biology 165(3): 373386. GM maize seed cost considerably more than standard non-GM seed. Dr. Hodgson's current extensio ISU Extension and Outreach The farmer will use an insecticide intended for control of stalk borer and broadcast it by using a boom spray. As they become larger or if the plants are mowed, terminated mechanically or burned down with herbicides, the stalk borers migrate into adjacent corn plants to complete their development.
In Tanzania and Kenya, losses of about 12% of maize grain for every 10% plants infested by B. fusca were reported. In some cases the elimination of winter cover crops, or good weed control, may be necessary to prevent stalk borer damage. Tassels may be deformed, and silking may be delayed, which can result in yield losses. When planting, standard maize seed the best method of prevention is being proactive. Many plants will have an unnatural growth, being twisted or bent over, presenting a stunted appearance and will not produce an ear. In a conducive environmental, the life cycle of this insect can take 7-8weeks. Walker, P.T., and M.J. Hodson. Khan, Z.R., F.N. To be effective, insecticides must be applied before common stalk borer larvae have entered the stalk. 3rd International Neem Conference (Nairobi, Kenya, 1986). . Pupation occurs in the soil and moths emerge in August, September and early October. The AI indicates the potential population growth throughout the year. 105 Ag. 1976. Eggs can be found on dead vegetation inside curled leaves or tucked between the sheath and stem. Suppression indicates that a lower level of mortality is expected. Ames, IA 50011-2031 Table 2. There are longitudinal ridges and cross-ridges that form shallow pits. Chabi-Olaye, A., C. Nolte, F. Schulthess, and C. Borgemeister. Its hind wings are almost white with a smoky tinge and dark longitudinal lines indicating the veins. Make sure to read the label and follow directions, especially if tank-mixing with herbicides, for optimal stalk borer control. 2006. This condition is commonly called "dead heart.". Adult moths emerge in late summer to fall to lay eggs.
http://keys.lucidcentral.org/keys/v3/eafrinet/maize_pests/key/maize_pests/Media/Html/Busseola_fusca_(Fuller_1901)_-_African_Maize_Stalkborer.htm. A reduction by a factor of 13 is predicted for most parts of SSA lowlands, whereas an increase by a factor of 13 is predicted in most African highlands, particularly in East Africa (Ethiopia, Kenya, Tanzania) and Angola (Fig. The leaf sheath of the youngest unfolded leaf is the most attractive part for females to deposit eggs. Egg: Stalk borer eggs are 0.02 inches in diameter and somewhat flattened. The larvae are not highly mobile and typically only move into the first four to six rows of corn near their overwintering site. When scouting conventionally tilled fields, examine corn plants along fence rows, ditch banks, grass waterways, or where weed patches existed the previous year.
Larvae begin moving to cornfields when 1,400 GDD have accumulated, and peak larval movement occurs at 1,700 GDD. Some larvae bore in the cobs. The forewings also have a few clusters of small white spots (Photo 1). Calatayud, and J.F. Wadhams, N.Dibogo, A. Ndiege, G.Genga, and C. Luswetti. 2009 Purdue University.
Accessed on 20/11/2013. The negative r values below 16C and above 31.5C indicate that population size is decreasing due to high mortality or very low reproduction. Use the information in Table 2 to determine the economic injury level. Stalk borer hatch and migration to new hosts can be predicted using degree days (DD). Stalk borers can cause damage throughout a field where reduced tillage is practiced and/or where cover crops are used. It is easy to overlook infested soybean plants because neighboring plants grow quickly and fill in gaps. Lusweti, A., E. Wabuyele, P. Ssegawa, and J.R. Mauremootoo. Larvae have prolegs along the abdomen and are up to 40 mm long and 5 mm wide. The trap plant attracts the adult female. UNL web framework and quality assurance provided by the, Apply to the University of NebraskaLincoln, Give to the University of NebraskaLincoln, Institute of Agriculture and Natural Resources, Strengthening Nebraska's Agricultural Economy, 2022 Guide for Weed, Disease, and Insect Management in Nebraska (EC130), Stalk Borer Ecology and Integrated Pest Management in Corn, Begin scouting grassy field borders and corn, Make insecticide treatment decision in corn. Relationships of soil fertility and stem borers damage to yield in maize-based cropping system in Cameroon. Photo by Marlin Rice. Risks mapping under current and future climates, Changes in establishment and future distribution. Fully grown larvae can be 1 1/2 to 2 inches long. Larvae are found throughout the summer with pupation occurring in August. Corn between the two- and eight-leaf stages can be attacked by the migrating stalk borer larvae. Stalk borer is native to North America and present in most places east of the Rocky Mountains. Pests of graminaceous crops in South Africa. Larva: Young larvae are a distinct brownish-purple color with an orange head capsule that has a black stripe on each side. As infestation progresses, they invade the growing points causing dead hearts, whereby the central leaves dry and wither. Egg-laying on maize is usually concentrated on plants that are less than 2 months old. Effects of nitrogen and potassium combinations on yields and infestations of maize by, Chabi-Olaye, A., C. Nolte, F. Schulthess, and C. Borgemeister. Chabi-Olaye, A., F. Schulthess, and C. Borgemeister. Stalk borers tend to re-infest the same fields, so prioritize scouting fields with a history of stalk borers, paying extra attention to the field edges. Fully grown larvae are uniformly gray and up to 2 inches long (Photo 3). Annals of Applied Biology 84: 111114. The grayish moth, with or without silver spots on the forewings, appears in mid-August and September. Stalk borers typically only infest the first few rows of corn near ditches, fence rows, or waterways, but understanding how to scout for and identify stalk borers can help with management decisions. Scout your fields regularly to inspect for infestations of Stalk borer and take quick action when you identify a problem. Any weed control method that helps eliminate grasses will reduce the number of potential stalk borer egg-laying sites, reducing the probability of stalk borer damage the next year. It is therefore of great importance to control this pest in order to avoid these losses. The activity index (AI) indicates the potential population growth throughout the year. 2006. Though still under study and development, the use of traps (pheromone t traps), baits, and mating disruption may be used in future. Larval damage occurs from May through July. pp. When grass-type plants are not disturbed by tillage, stalk borer eggs may be present throughout the field and subsequent damage will not be limited to field margins. Scouting grasses at the edge of the field at this time may help one identify a potentially damaging infestation. Le Ru, unpublished data). Bulletin of Entomological Research 95: 417427. A primer on planting and managing push-pull fields for stemborer and striga control in maize a step-by-step guide for farmers. Effects of grain legumes and cover crops on maize yield and plant damage by Busseola fusca (Lepidoptera: Noctuidae) in the humid forest of southern Cameroon. Since smaller plants are more heavily damaged, earlier planting may allow corn to outgrow the most severe damage. Fr. POTENTIAL GLOBAL AND REGIONAL DISTRIBUTION AND ABUNDANCE OF AGRICULTURAL AND HORTICULTURAL PESTS AND ASSOCIATED BIOCONTROL AGENTS UNDER CURRENT AND FUTURE CLIMATES, 4.4.2 Maize Pests / Maize stalk borer, Busseola fusca (Fuller 1901), Taxonomic position: Insecta, Lepidoptera, Noctuidae, Authors: G. Ongamo, N. Khadioli, B. Understanding the common stalk borer life cycle and behavior is critical to selecting management practices to reduce damage in corn. Photo 3. 3DF). A leading agrochemicals, seeds and farm equipments company in Africa. The ERI>0.95 reflects the B. fusca current distribution in SSA (Fig. Look for feeding damage and dissect damaged plants to see if live larvae are present. ICIPE Biennial Scientific Report 20042005. and a trap plant, such as Napier grass (Pennisetum purpureum Schumach.) The models established to describe the development time, survivorship, and reproduction were compiled into an overall stochastic phenology model that allows the B. fusca life-table parameters to be estimated according to temperature (see Annex 7.3.14). They may also enter small corn plants from the whorl and work downward, causing part of the plant to wilt and die. 2011. Distribution, pest status and agro-climatic preferences of lepidopteran stem borers of maize in Kenya.