agnet-l : Message: Agnet April 19/04

Agnet April 19/04

Greenpeace battles gene-modified food in Australia

EU food agency says Monsanto GM maize type is safe

GM soya saved us, says angry Argentina after 'superweed' claim

Hybrid rice corn to feed Philippines' rising population

Opportunity blocks

Europe's ban on GMOs is still firmly in place

Planting practices for minimizing GMO contamination of non-GMO corn

What is Bt corn?

Insecticide seed treatments for corn

How deep should I plant corn?

SCN-resistant soybean shouldn't lead to complacency

However, the product shouldn't be considered a cure-all. Traditional management practices are still important, stresses an Ohio State University plant pathologist. CystX, a patented technology owned by Purdue Research Foundation, offers broad-based resistance to soybean cyst nematode in that it prevents the pest from reproducing on the plant's roots. OSU plant pathologist Mac Riedel said the technology is a good way of controlling soybean cyst nematode populations but other management practices, such as soil sampling and crop rotation, should not be forgotten. "With such a product on the market, it will be very easy for growers to continuously plant the resistant variety year after year after year. It's just a natural tendency," Riedel said. "But, like with other varieties, eventually females will be selected that will be able to reproduce on this line and we will be back to where we started." Hence, the importance of crop rotation, Riedel said. "It's so easy to control this pest," he said. "All you have to do is rotate your crops." Soybean cyst nematodes (SCN) feed on the roots of young plants, which prevents roots from taking up vital nutrients. The result is a drop in yields and economic losses. The best management tool to control SCN populations is to sample fields with a history of problems and rotate resistant varieties based on relative egg counts. Yield loss threshold of SCN begins at 200 eggs per cup of soil. At 2,000 eggs per cup of soil, most susceptible soybean varieties suffer significant economic losses. At 5,000 eggs per cup of soil, growers should avoid growing soybean varieties altogether, even resistant varieties. Riedel said that growers should keep this in mind even when planting a resistant variety like CystX or a resistant soybean variety with similar Hartwig-type resistance. One reason is based on Ohio State research that has shown a persistent weed called purple deadnettle to be a host for soybean cyst nematode.

April 18, 2004The Yomiuri Shimbun The Agriculture, Forestry and Fisheries Ministry plans to label some stock farm products as organic under the Japan Agricultural Standard, government sources said Saturday. The ministry plans to introduce the new labeling system in fiscal 2005, after the JAS Council, an advisory panel to the agriculture, forestry and fisheries minister, discusses the proposal. The organic JAS label indicates how farm products are grown--whether, for example, chemical fertilizers were used. The plan aims to include beef, milk, chicken meat, eggs and other stock farm products as candidates for the labels. A system of the organic JAS labeling has already been introduced for vegetables and other farm products, and some processed foods made from farm products such as fermented soybeans. The ministry decided to expand the scope of the system to include stock farm products because consumers have become increasingly concerned about product safety in the wake of recent occurrences of mad cow disease and bird flu, officials said. Under the new system, stock farm products may be eligible for the organic JAS label if they fulfill six criteria, including: Livestock were fed with pasture grass that grew in fields where neither chemical fertilizers nor pesticides were used for at least two years. Livestock were raised in an environment with sufficient sunlight. Antibiotics were not mixed in feed. The ministry plans to cover processed stock farm products, such as sausage and cheese, under the new organic JAS label, in addition to meat and milk. The ministry also plans to categorize both agricultural and stock farm products as organic so the labeling can cover a wide range of products, such as baked goods.

April 19, 2004European Commission- Health and Consumer ProtectionThe complete document of the following can be viewed from:http://europa.eu.int/comm/food/fs/rc/scph/agenda/agenda33_en.pdfAgenda: Meeting of Thursday 22 and Friday 23 April 2004

April 16, 2004The Bulletin Vol. 4 University of IllinoisSuzanne Bissonnettehttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=7Viruses are mild and scattered this season. Dennis Epplin, crop systems educator at Mt. Vernon Center, reports probable barley yellow dwarf virus (BYDV) in the area. Matt Montgomery, crop systems educator at Sangamon-Menard unit, indicates BYDV and soilborne wheat mosaic virus (SBWMV) symptomatology in his area. Primary symptoms of SBWMV are light mottling of the leaves accompanied by an overall light yellowish to lime-green discoloration of affected areas. Although these symptoms (particularly if they wane in the next week or so) are characteristic of soilborne wheat mosaic virus infection, the only way to know with certainty is to have the live tissue tested for the virus. Varietal characteristics, nutrient imbalances, and viral diseases all can be causes of leaf discoloration this time of year. If viruses are going to be a problem, symptoms should be well evident by now. The most common virus diseases early in the spring are barley yellow dwarf virus (BYDV), soilborne wheat mosaic virus (SBWMV), and wheat streak mosaic virus (WSMV). Each virus can cause damage to the plants, with BYDV being the most damaging in Illinois. Barley Yellow Dwarf Virus Aphids carrying the virus transmit it to wheat plants through their saliva when they feed. The most serious yield loss results from fall infection by viruliferous aphids feeding on wheat seedlings. Fall infections typically result in stunted plants and fewer tillers when spring growth resumes. Leaf discoloration is usually the most notable early-season symptom. Leaves may be varying shades of red to purple, pinkish yellow to brown. As the plant continues to grow, older leaves typically begin to die back from the tip and may feel somewhat leathery, while the new leaves begin to discolor. Spring infections occur as well but commonly only discolor the flag leaf and do not cause significant yield reductions. Leaf-reddening symptom of BYDV.Soilborne Wheat Mosaic Virus The other most common disease causing leaf discoloration this time of the year is SBWMV. It is usually one of the first plant diseases reported in the spring. An unusual aspect of this disease is the mode of transmission to wheat plants. The virus is transmitted to the plant by a soilborne fungus. The virus is carried in the fungus, and when the fungus enters wheat roots it transmits the virus. The fungus is a water mold and favors low, wet areas of the field, which is usually where the disease is first seen. Plants infected with SBWMV can show two types of symptoms. The first symptom is leaf mottling, which appears as a light green and light yellow mosaic on the leaves. The mottling will only be seen very early in the season. The second symptom is stunting, to the point where the wheat plant looks like a rosette when growth begins in the spring. Under good growing conditions, the infected plants may recover somewhat. SBWMV is not commonly a yield-reducing disease, because higher spring temperatures inactivate the virus and symptoms then do not appear on new leaves. Yield reductions with SBWMV are uncommon, except where extremely susceptible plants are present. Most wheat varieties are resistant to this pathogen, although resistance can vary. Wheat Streak Mosaic Virus Initial foliar symptoms of WSMV, also known as yellow mosaic virus, typically show up in the spring, too. The pattern of the disease in the field is tied to the distribution of its vector, the wheat curl mite (Aceria tulipae). Affected wheat plants are typically stunted, with mottled, streaked leaves. The streaks consist of yellow discontinuous dashes running parallel to the veins. Leaves that are heavily infested with mites tend to remain upright, and the margins of the leaf may roll inward. Symptoms tend to get worse as the weather warms up, and severely infected plants may produce sterile heads or die. Yield loss depends on when infection took place. Fall-infected plants can experience severe yield loss; early-spring infection, light to moderate loss; and infection after jointing, minimal loss. Streaking of leaves from WSMV.Disease cycle. Viral diseases of wheat usually produce symptoms in newer growth. Viruses typically cause stunting of plants as well as a discoloration of leaves, with the most common color being either red or yellow. In some viruses, streaking of the leaves or a mosaic pattern also can be seen. Viruses are unusual pathogens, because they neither require a food source nor do they have the typical physiological processes associated with other biotic pathogens. Viruses are vectored to plant cells, release their genetic material, and cause the plant cell to replicate more copies of the virus. Most viruses consist of only a genetic and a protective protein outer coat. Once inside plant cells, the virus sheds the protein coat, and the genetic material begins replicating the virus. Management. The most common method of virus management is to plant resistant wheat varieties. These varieties do not allow virus replication to occur, and the infection is stopped early. Other control measures are directed at reducing the time the plants are in the field when vectors are active, which explains the recommendation to plant after the fly-free date, when insect activity is reduced. Systemic insecticide seed treatments have also shown some success. Diagnosis. So which virus may be in the field? First, rule out any other problems that may have caused the symptoms, such as winterkill, nutrient imbalances, and herbicide carryover. This is an important step. Next, find out what virus resistance the variety is supposed to express. Most of our varieties demonstrate good resistance to SBWMV, whereas good resistance to BYDV is lacking. If those things don't help, then the pattern may help you decide. BYDV usually first shows up in a typical insect-type pattern. Infected patches occur randomly in the field or are associated with areas in which viruliferous aphids may have been feeding, such as grassy areas on field edges. Also, BYDV infection is completely dependent on aphid movement, and symptoms can continue to spread throughout the season. SBWMV, on the other hand, is most typically associated only with low, wet areas of a field, and symptoms do not continue to spread throughout the season. The Plant Clinic at the University of Illinois or our Digital Diagnostic System can only make a visual estimation of the presence of a virus in a wheat plant. We cannot tell you which virus is actually present, based on the visible symptoms. To have a virus positively identified, it is necessary to send virus-infected tissue to a lab such as AgDia (www.agdia.com) for serological testing. Fresh plant material is needed for serological analysis because the tests use fresh plant sap.

April 16, 2004The Bulletin Vol. 4 University of Illinois Emerson Nafzigerhttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=10There have been a few reports of soybean being planted already, probably reflecting a deliberate choice to plant soybean before corn. Our data from planting date work on soybean suggest that planting soybean before corn, at least when planting starts in mid-April, is probably not a good management choice. Both corn and soybean are expected to yield a little less when planted before April 15 than after April 25, but our data tell us to expect the percent yield loss from earlier planting to be greater with soybean than with corn. More important, the planting date plateau--the range of dates over which we would expect little effect of planting date--is longer and starts later for soybean compared to corn. While we can't forecast how planting date responses might vary among years, our data show that the "average" ideal planting dates are about April 20 to May 5 for corn, and April 25 to May 20 for soybean. If we accept these, then it makes little sense to ever plant soybean before corn planting is finished, even if we don't believe that planting in mid-April causes lower yields. The risk of not getting corn planted on time is simply greater than this risk for soybean. With the weather turning warmer this week and many fields in good shape to plant, we expect a fast start to planting by mid-April. I see little reason not to start planting in central and southern Illinois, as long as the soil is in good shape. The fact that the weather seems to be in a relatively dry pattern suggests that we needn't rush to get done by April 20 or 25, but if the weather continues to be dry, it will be useful to plant before the soil dries out to below planting depth. Planting this early, with the possibility of a return to cooler and (especially) wetter conditions, means that we should not increase planting depth; seed lying in dry soil until it gets rain to emerge is usually better than seed planted too deep and trying to come up when it's cold and wet. It's impossible to predict emergence conditions when we start to plant early, but we do know that dry conditions are almost always better than wet conditions, regardless of temperature. We have known corn seed to lie in dry soil for a week or two with little ill effect, as long as it eventually gets rain to emerge. Of course, it's safer to have enough soil moisture at planting for the crop to emerge. This may mean skipping that last "leveling" tillage pass for some people and thus avoiding the exposure of more soil to drying that such tillage causes. Crusting is reported to be serious in some of the fields that were worked, planted or not, in March. The degree of soil crusting always seems unpredictable--we normally associate the greatest crusting with warm, dry conditions after a beating rainfall. In this case, we had the rainfall, but drying conditions didn't develop very strongly. From March 20 to 31, we accumulated about 75 growing degree-days (GDDs) at Urbana but have had only about 60 GDDs since April 1. The 130 or so accumulated after the crop was planted in March (the heavy rains were March 25-26, and most planting was before that) should be enough for corn to emerge, though the upside-down pattern of warmer early followed by cooler weather may have thrown off the prediction that emergence should start within about 120 GDDs after planting. Breaking a crust to allow emergence after this kind of start is probably not going to work very well, given the strength of the crust. The cool temperatures the seedling has already experienced may also have decreased its ability to emerge, due to its having used up seed-stored materials and diseases that might have infected the seed. We usually are pleased when planting can start early and end on time, as it appears may happen this year. Before we get too carried away, though, we should recall that early starts and finishes to planting in Illinois have not always meant high yields. It's good if it's dry in April, but only if it remembers to rain during the season.

April 16, 2004The Bulletin Vol. 4 University of IllinoisMike Grayhttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=5The planters are rolling across the east-central Illinois landscape, and many thousands of acres of corn have been planted. As we move into mid-April, warmer temperatures will fuel the frenetic corn-planting pace. Soybean planting can't be that far off, and with it the interest and curiosity in soybean aphids will intensify. Will the 2004 season bring a repeat of 2003 with respect to this new insect pest? Or will 2004 lull us into complacency regarding the management of soybean aphids? Predictions abound. Those of us familiar with agriculture know that ultimately we will have to experience another growing season to answer these questions. In the most recent issue of the Annals of the Entomological Society of America (vol. 97, no. 2, March 2004), eight scientific articles were published concerning the biology and ecology of the soybean aphid. I've read through these intriguing articles and thought it might be helpful to share with the readers of the Bulletin some facts gleaned from these publications. Provided here is a primer of sorts concerning soybean aphids that may become more useful as the 2004 season unfolds. Soybean aphids.The soybean aphid is an insect native to eastern Asia (northern China, Korea, Japan, the Philippines, Malaysia, Indonesia, and Australia). This pest was discovered in North America in July 2000. Initial infestations were reported in Wisconsin, and by summer's end entomologists in 10 states of the north-central region of the United States had confirmed pockets of soybean aphids in soybean fields. Presently, soybean aphids now occur in 21 states (at the conclusion of 2003) and three Canadian provinces. Soybean aphids lead rather complex lives, with alternate hosts and asexual and sexual cycles. For the most part, the life cycle of soybean aphids in the United States closely resembles the life cycle in China and Japan. Overwintering hosts in these Asian countries are Rhamnus davurica Pallus and Rhamnus japonica Maxim. To date, there are two confirmed overwintering hosts in the United States--Rhamnus cathartica L. (common buckthorn) and Rhamnus alnifolia L'H�ritier (native alderleaf buckthorn). In addition to these hosts, fall migrants (gynoparae--from soybean plants to overwintering host) and oviparous nymphs (reproducing by eggs laid by the female) have been found on glossy buckthorn (Frangula alnus). David Voegtlin, an entomologist with the Center for Economic Entomology, Illinois Natural History Survey, could not confirm this species as a "primary host." Both common and glossy buckthorn species are exotic, whereas the alderleaf species is native to the United States. As the name suggests, common buckthorn is very abundant in the north-central region of the United States. Finding spring colonies of aphids on common buckthorn has proven very challenging. This had led to some speculation that there might be other hosts entomologists are yet unaware of. Because Rhamnus davurica and the native alderleaf buckthorn species are relatively uncommon in the north-central region, it seems unlikely that either serves as a significant production site each spring for aphids to subsequently infest soybean fields. Efforts to rear soybean aphids on kudzu, Pueraria lobata (Willd.), in Illinois have failed. In 2003, soybean aphids were reported in soybean fields on June 3 in Minnesota and June 11 in Indiana. These very early sightings were approximately 1 month earlier than first observations in soybean fields the preceding two seasons. So predicting the first occurrences of soybean aphids in 2004 is anything but certain. It has been suggested that mild growing conditions in 2003 contributed to large densities of soybean aphids and widespread economic infestations in the north-central United States. The optimum temperature range for development of soybean aphids is reported as being 22 to 25�C (71.6 to 77�F). If a mild June occurs in 2004, this could contribute to increasing densities of soybean aphids in some locations. Within soybean fields in the vegetative growth stages, soybean aphids are frequently discovered in colonies on the growing points. As plants reach the reproductive phases of development, aphids become more evenly distributed throughout the plant. It has been reported that host quality declines as soybean plants mature, potentially lowering the fecundity of soybean aphids. The phenology of soybeans may significantly affect the numbers of gynoparae (winged female fall migrants) and winged males that are able to successfully leave soybean fields prior to harvest and reach buckthorn. Early maturation and harvest of soybeans may interfere with a successful migration of winged females and males to buckthorn. Late-planted beans and double-cropped soybean fields may improve the chances for this fall migration to occur. We will continue to learn much more about soybean aphids in the United States as we develop appropriate IPM programs for this interesting insect pest. Here are some interesting tidbits that I gleaned from the aforementioned articles. The number of generations of soybean aphids in China has been reported from 10 to 22 per year. In China, generation length ranged from 2 to 16 days. It has been reported that at 78.8�F, a mean (per female) of 58 and 38 nymphs were produced from wingless and winged soybean aphids. Odor eminating from soybean plants appears to be influential in attracting soybean aphids. The Chinese literature indicates that soybean aphids are important vectors of soybean mosaic virus. This disease is common in China. Soybean aphids have been reported as vectors of other diseases, such as soybean stunt virus, soybean dwarf virus, abaca mosaic, beet mosaic, tobacco vein-banding mosaic virus, bean yellow mosaic virus, mungbean mosaic virus, peanut mottle virus, peanut stripe poty virus, and peanut mosaic virus. In China, lady beetles are believed to be the most important predators of soybean aphids. The multicolored Asian lady beetle, Harmonia axyridis Pallas, is one of several lady beetle predators in China. Other lady beetle species include Propylaea japonica Thunberg and Coccinella septempunctata L. Entomologists at Purdue University have identified insidious flower bugs (Orius insidiosus Say) and multicolored Asian lady beetles (Harmonia axyridis Pallas) as "potentially key predators" of soybean aphids. They speculate that predators such as these that appear in greater densities earlier in the season in soybean fields may be more apt to prevent soybean aphid outbreaks than predators more commonly observed later in the season. In China, the density of overwintering soybean aphid eggs was strongly correlated with subsequent infestations during the upcoming growing season. Severe outbreaks resulted when the number of overwintering eggs was greater than 10,000 per 100 buckthorn branches. How's that for a predictive threshold? Host plant resistance research in China has shown that some varieties are highly resistant to soybean aphids. In the late 1980s, it was reported that two "highly" resistant varieties were found among 181 varieties that were screened. I suspect that we will eventually utilize this IPM approach extensively in the United States for this insect pest.We will continue to learn more about soybean aphids over the years and hopefully offer an effective integrated management approach for this new and significant threat to soybean production. I continue to be distressed about sales promotion tactics for certain insecticides targeted against soybean aphids. These tactics run completely counter to the IPM philosophy. In general, the sales campaigns promote the treatment of soybean fields for soybean aphids with little to no regard for aphid thresholds, aphid densities, or knowledge of predator densities. These promotional campaigns indicate that the cost of the product will be returned if yields don't pay for the treatment expenses. This is not a responsible approach to soybean aphid management nor is it an acceptable product stewardship philosophy. This issue will be addressed in greater depth as the season progresses.

April 16, 2004The Bulletin Vol. 4 University of IllinoisDawn Nordby and Aaron Hagerhttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=9The vast majority of herbicide options for weed control in wheat are for control of broadleaf species. Proper herbicide application timing is critical to achieve good weed control. All herbicides commonly used for weed control in Illinois wheat also have application restrictions based on wheat developmental stage. All of these herbicides have maximum crop-growth stages for application, most indicating applications must be made before the jointing stage. Table 2 contains information about the herbicides labeled for use in small grains. Before making any herbicide application, consult the respective herbicide label for additional information.Wild garlic, especially in the southern portion of Illinois, is an important nonbroadleaf species that can result in significant economic losses if left uncontrolled. Wild garlic (Allium vineale) is a perennial species in the Lily (Liliaceae) family. Seedlings are grasslike, with hollow leaves that are circular in cross section. The plant reproduces from seed (rarely), aerial bulblets, and underground bulblets. The aerial bulblets are produced in a cluster at the top of the stem, are surrounded by a papery membrane, and are very difficult to separate from the wheat seed. These bulblets can impart a "garlicy" odor/flavor to wheat during the processing stage and are thus very undesirable. Significant dockage can result if wild garlic bulblets are present when the wheat is delivered to the elevator. Wild onion (Allium canadense) is a similar species, except that the leaves are flat and not hollow; it produces no underground bulblets; and the aerial bulb has a fibrous, net-veined outer coating, unlike the thin, membranous outer coating of wild garlic.Harmony Extra (thifensulfuron + tribenuron) or Harmony GT (thifensulfuron) is often used to control wild garlic in wheat. These herbicides are very effective in controlling wild garlic and can provide control of several other weed species (Harmony Extra will control chickweed, but Harmony GT will not), but Harmony Extra will not control wild onion. The label allows Harmony Extra to be applied with liquid fertilizer as the carrier instead of water, but this may increase crop response. Wheat herbicide effectiveness ratings appear in Table 3. As the wheat crop approaches maturity, producers may elect to make a preharvest herbicide application. Products that can be used as a preharvest treatment will be discussed in a future issue of the Bulletin.

April 16, 2004The Bulletin Vol. 4 University of IllinoisKevin Steffeyhttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=3The corn planters are rolling and will continue to roll across Illinois as long as the weather holds. Some corn has emerged in southern counties. Consequently, reports of insect injury are not far behind. In previous articles in the Bulletin, we have discussed, in some detail, such early-season pests as black cutworms, white grubs, and wireworms. Throw in some armyworms, billbugs, flea beetles, grape colaspis, seedcorn maggots, southern corn leaf beetles, and stink bugs, and you have a full array of so-called secondary insect pests that can threaten corn production. We have stated more than once that early planting has contributed to the increase in reports of problems caused by several of these pests, so we won't be surprised if some of them make their presence known this spring. Visits to cornfields early in the season are more common than they are later in the season, after corn has attained some height and temperatures are more uncomfortable. And as you know, all sorts of problems can occur early in the season, at a time when everyone in the "neighborhood" can see them. Some problems, of course, can be cured, whereas we often have to live with other (e.g., abiotic) problems. So it is extremely important to diagnose early-season problems (late-season, too, for that matter) so that unnecessary treatments are avoided. Spraying an insecticide to correct a problem that is the result of a fertility issue does not make a lot of economic sense. In March 2003, several Extension specialists from the University of Illinois conducted a diagnostics workshop in Bureau County. Specialists involved in the workshop were Bob Hoeft (soil fertility), Dean Malvick (plant pathology), Terry Niblack (nematology), Christy Sprague (weed science), and me. Jim Morrison, Extension crops systems educator in Rockford, was the emcee, and he also discussed crop development and abiotic factors that affect crops. The workshop was designed for the specialists to progress chronologically through the season, indicating what types of problems could occur during any given crop-growth stage (e.g., corn emergence [VE] through V4-V5). The specialists interacted during each stage of the workshop so that all problems for a given crop-growth stage were addressed, rather than isolating problems by discipline (e.g., entomology). The workshop was well received because of the interaction among the specialists and those attending the meeting. Plans have been discussed to create a "workbook" of diagnostics, based on the visuals used at the workshop. I explain the workshop as a setup for a link to some of the slides I used to discuss diagnosis of early-season insect problems in corn. The diagnoses are from planting to emergence (VE) and from emergence (VE) to V4-V5. A handful of slides provide some text for foundation, and the rest of the slides include photographs of injury and some of the insects (or related organisms) involved--armyworm, billbugs, black cutworm, carrot beetle, chinch bug, (other) cutworms, flea beetles, grape colaspis, hop vine borer, seedcorn beetles, seedcorn maggot, slugs, southern corn leaf beetle, stalk borer, webworms, white grubs, and wireworms. I owe thanks to my friend Marlin Rice, extension entomologist at Iowa State University, and to Gary Munkvold (formerly at Iowa State University) for their photos. Click here to download slides.The slides include both common and relatively uncommon insects. In fact, you will never encounter some of the insects included (the same would hold true for the insects listed on many insecticide labels). However, I wanted to be as complete as possible. Nonetheless, it's always possible that you could encounter an insect or related organism not included within the slide set. So don't hesitate to send me photos and observations of your encounter. As you are monitoring fields of corn early in the season, watch for symptoms of insect injury--cut, missing, stunted, or wilted plants; discoloration; distorted growth; gouges in stems; leaf tissue missing; reduced plant populations. Many of these symptoms also can be caused by other factors. So keep your diagnostic skills sharp, and make informed decisions.

April 16, 2004The Bulletin Vol. 4 University of IllinoisKelly Cookhttp://www.ipm.uiuc.edu/bulletin/article.php?issueNumber=4&issueYear=2004&articleNumber=2Reports of black cutworm moth flights were few and far between this past week. In fact, the only locations reporting significant flights of black cutworm moths were in southern Illinois. Ron Hines, research specialist at the Dixon Springs Agricultural Center, reported significant moth flights in Pulaski, Pope, and St. Clair counties, with St. Clair County getting hit hard. Ron also noted in an e-mail this week that corn is beginning to emerge in the area, and with expected warm temperatures for the remainder of the week, cutworm feeding could be significant. As corn planting begins to coincide with moth flights, it's important to scout fields that are especially attractive for egg laying. Fields or areas of fields in which early-season weeds were growing at the time moths flew into the area are at a higher risk than weed-free fields. If tillage or herbicides eliminate weeds 1 to 2 weeks before planting, any black cutworms that had been present probably starve to death. The presence of weeds only a few days before planting increases the likelihood of cutworm damage if larvae are present in the field. Begin watching emerging seedlings carefully for early signs of cutworm feeding (pinholes in the leaves) and for plants that have been cut off by larger larvae. View the black cutworm fact sheet for more information on black cutworm injury. The warm temperatures and southerly winds could bring cutworm moths to the rest of the state in the near future, too. Keep updated on moth flights in your area with the Insect Monitoring Network. Each week, moth flights are reported by volunteers around the state and posted on the Web. For now, keep your eyes peeled for feeding in emerging corn fields.

April 16, 2004Integrated Pest Crop Management Newsletter Vol. 14, No. 5 University of Missouri-Columbia Fred FishelLast week, Wayne Bailey discussed the early detection of adult black cutworm moths caught in our trap and some of our volunteers' traps around the state. These flights are again picking up this week with the warmer temperatures and wind currents arriving from the south to southwest, bringing the adult moths into the state. Based on initial detections during late March, we anticipate cutting to begin on corn during the first week of May. With more trap catches of moths this week and more anticipated in the coming weeks, cutting could potentially occur over an extended period of time. How does the trapping and forecasting program make predictions? Several assumptions must first be made, and then historical climatology data gives us an indication of when we should be scouting for cutting activity. Here's an example of how it works. Let's say we have an intense catch of moths in our trap on March 26 in Boone County, as was this season's situation. An intense trap catch is defined as at least 17 moths caught in a one-night period in a Texas metal cone trap. Some of our volunteers also use the less efficient sticky wing trap, and an intense catch with this type of trap is considered to be at least 8 moths caught over a two-night period. Since moths are flying into the region, one of the assumptions for the forecasting model is that the moths will be laying their eggs upon arrival. Historical studies of this insect pest have carefully documented the number of degree days (base of 50 degrees F) that must occur for its developmental stages. The following table will show you how these insect developmental stages coincide with the accumulated degree days Once an intense catch occurs, that date is entered into the forecasting model. The model's user is also asked to select the location of the nearest MU Extension Climatology Station from the drop-down menu. These stations are operated in a variety of locations around the state. For each of these station locations, 30-year historical weather data is stored on file, and the average temperatures are used to make the degree-day calculations for that particular location. For our example, our date is entered and we have selected Columbia-Boone County. Press �submit,� and the model is off and running, instantaneously providing us with the predicted degree-day accumulations, insect development stages and their associated activities. We see from this piece of information that we should be in the field on the lookout during the first week of May, at least here in mid-Missouri. Is this a guarantee of what will happen during the first week of May? There are few guarantees in our lives as well as the lives of the black cutworm. Looking back at the 2003 season, we had a couple of factors enter into the picture that didn't exactly follow 30-year historical averages. First, in April 2003, we had tremendous numbers of moths caught in some of our traps, setting up of what appeared to be a high damage potential. After the forecast model was run, we were all set to begin scouting, but during the first 15 days of May, our location received 3.5 inches of rainfall along with cooler than average temperatures. Black cutworm larvae most likely can't survive flooded soil conditions, if they were present in the first place. Also, there was no guarantee that the moths laid a tremendous number of eggs upon their arrival � certain conditions may have inhibited egg laying. In our location, no damage was observed, though it was predicted to occur. Remember, this is only a prediction that is based on what is considered to be average, and I don't think that I have actually experienced �average� since my arrival in 1992. However, there is always potential, and we have a tremendous tool to help us alert our clientele of when we should be in the field. For using the model and learning more details about the program, visit http://agebb.missouri.edu/weather/reports/bcwforecast.htm#monitor. It is selfexplanatory and will allow you to run as many simulations as you wish. There is also a list of our volunteer trappers around the state whom you can contact concerning the trap data for your area.

April 16, 2004Integrated Pest Crop Management Newsletter Vol. 14, No. 5 University of Missouri-Columbia Bill Casadyhttp://ipm.missouri.edu/ipcm/archives/v14n5/ipmltr4.htmIf I could have just one piece of really good equipment, it would be a planter. The planter is one of the most complicated and precise pieces of equipment on the farm, and the primary piece of equipment needed to get a crop off to a good start. Think about what's involved for a moment. A planter places about 30,000 seeds about 7 inches apart and about 11/2 to 2 inches deep in every planted acre. At planting time, there are many things that can go wrong. Tillage ultimately affects both the success of the planter and the root system of the seedling. Tillage at the wrong time or under the wrong conditions is often a primary reason for substandard results. Tillage under wet conditions causes deep compaction, destroys soil structure and results in high-density chunks of soil or clods that have very little immediate value for a growing crop. Excessive, or perhaps, obsessive/compulsive tillage causes shallow compaction at the depth of tillage that limits root growth. These substandard roots ultimately result in lower yields especially in years where drought stress follows. Many of us remember how those somewhat �slower to thrive� no-till fields in 2003 ultimately outperformed heavily tilled fields plagued by shallow compaction and shallow roots. Now, having avoided primary and secondary tillage mistakes, the rest of the fate of the crop that we can control rests primarily on how well we adjust the planter. After all, the reason planters are designed with so many adjustments is that they need to be adjusted. A good operator knows how every adjustment affects planter operation and doesn't hesitate to get out and check the job. That means digging on hands and knees, counting seeds and closely observing where those seeds are placed. Poor seed placement in any direction and in any substandard condition is cause for concern. Placed too shallowly, young seedlings are more susceptible to frost or to damage from soil-applied herbicides and may hinder permanent root development during hot, dry weather. Non-uniform spacing within the row leaves holes in the canopy or causes closely spaced plants to fail to thrive from the competition. A poorly closed seed trench exposes seed to pests and may allow the seed to sit and rot. Seed placement can always be improved by taking the time to adjust the planter throughout the season as soil conditions change, by keeping precision components in good shape and by operating the planter at a reasonable speed. Read and understand the operator's manual for the planter and make appropriate adjustments as needed. Then give closure to planter problems by waiting to plant until the soil is ready. For more information, see �Sowing machines need precision of a sewing machine� at http://ipm.missouri.edu/ ipcm/archives/v12n5/ipmltr1.htm and �Planter banter� at http://ipm.missouri. edu/ipcm/archives/v13n3/ipmltr3.htm.

April 13-20, 2004C.O.R.N Newsletter 2004-09Ohio State UniversityAnne Dorrancehttp://corn.osu.edu/index.php?setissueID=32#FIt�s not here in the continental United States. I�ve been getting a lot of questions over the past few weeks concerning soybean rust and thought I would let everyone know what the status is of this pathogen. There is a Technical Working Group for Soybean Rust, comprised of scientists from all of the land grant institutions and USDA, representatives from the soybean commodity boards and Dept. of Agriculture officials across the U.S. There is a conference call, approximately every other month, plus various presentations at the meetings I have attended this winter. In fact, I leave for Maryland on Monday (April 12) for another meeting on soybean rust. As we have mentioned before there are four possible routes of entry of this rust fungal pathogen into the U.S.: 1) via the Central American land bridge; 2) winds of hurricane via the Caribbean; 3) spores on shipments of seed or meal and 4) an act of bioterrorism. In all likelihood, the last two are very unlikely due to biology and the nature of this pathogen, and a higher likelihood for routes 1 and 2. When this gets here, we do have a management plan in place. Officials at the Ohio Dept. of Agriculture, USDA, PPQ, Pat Lipps and myself met last month and drafted a response plan. Because soybean rust is a select agent and does not occur here in the US, there are procedures in place for the first find and follow-up notification. Once soybean rust becomes established we will manage this disease with two disease management strategies: 1: fungicide applications and 2: host resistance. Host resistance is not going to be like the Rps genes for Phytophthora sojae, but more along the lines of partial resistance used for gray leaf spot on corn and mildew for wheat. This rust adapts very fast, within a year to R-genes that have been deployed. One of the terms researchers have used is called �slow rusting� types. Many of the companies are already screening advanced lines in research stations around the world. USDA is currently screening the soybean germplasm collection. We will hopefully hear about these results soon. Fungicide applications will be necessary to manage this disease, but this will vary greatly year to year. The primary driving force will be the environment - how early infections begin in the southern US and how soon they begin to travel north. Current data suggest, that this fungal pathogen will not be able to overwinter here in Ohio. The good news, is that the reports from Brazil during 2003 indicate that many fungicides work and there will be many choices. We currently have 3 materials registered in the U.S. and the E.P.A. has approved the first material for section 18. We wrote an application two weeks ago for Ohio to be added to this Section 18. The catch on the Section 18s is that they do not go into effect until soybean rust is found in the continental U.S. Research at Ohio State University � during 2003, with the help of Mark Loux and his team, we looked at the application of fungicides in combination with glyhosate. Applying fungicides to soybeans is going to be expensive and if we can save application costs then this will be a big help in preserving profits. This maybe too early for most fields, but it is good to get this data in ahead of time. During 2004, we will repeat this experiment, plus we have several trials planned to examine some of these materials alone and in combination with insecticide. We may also have soybean aphids to continue to manage. Over the summer, we will keep you posted on what may or may not develop during the growing season. Next winter, we will begin a series of articles on fungicides. I hope this answers some of your questions. I have total confidence that we will be able to manage this disease once it gets here, it�s likely to eat at our profits the first few years.

April 13-20, 2004C.O.R.N Newsletter 2004-09Ohio State UniversityRobert Mullenhttp://corn.osu.edu/index.php?setissueID=32#GThis is an often asked question, which unfortunately does not have a simple answer. Like most agronomic questions, there is no all encompassing solution that will work equally across all field conditions and environments. When making a decision on a nitrogen (N) source, economics, soil conditions, and climate must all be considered. Nitrogen applied as anhydrous ammonia, urea, urea-ammonium nitrate (UAN), etc., if applied at equivalent rates of N, all contribute the same amount of N to the soil. Plants do not prefer one formulation over the other. Anhydrous Ammonia Because anhydrous ammonia (82% N) has historically been the cheapest source of N, it has been the most popular. Due to the nature of anhydrous, it must be injected into the soil which increases its cost of application. Improper sealing behind injection equipment can result in considerable losses of N. Care should also be taken to inject anhydrous at least 6 to 8 inches into the soil. This is especially important if planting just after application of N. Anhydrous ammonia can cause seed injury. Dry Formulations With the cost of anhydrous production within the U.S. rising, the price differential between anhydrous ammonia and alternative formulations has decreased. Urea (46% N) is the most popular dry source of N. Its high N analysis and cheap cost make it an attractive alternative to anhydrous ammonia. Caution should be exercised when surface applying urea in no-till production systems. Considerable losses of N by volatilization can occur, especially if dry weather follows application. Application of urea would ideally be followed by a small rainfall event or incorporation. Ammonium nitrate (34% N) is another dry formulation consisting of 50% ammonium and 50% nitrate. Its popularity has decreased in recent years. In fact, some retailers no longer sell it in bulk. Ammonium nitrate is an attractive alternative to anhydrous because it does not contain any urea, meaning it is not susceptible to volatilization losses allowing for surface application. However, it is easily dissolved with very little surface moisture making it susceptible to leaching and denitrification. Liquid Formulations Liquid formulations of N, primarily as urea-ammonium nitrate (UAN � 28 and 32% N), have gained popularity in recent years. Its ease of application and handling as well as comparative pricing with dry formulations has aided its adoption rate. Due to the nature of UAN, broadcast application in no-till systems can result in considerable interception of the material by residue. Dribble applications of UAN can decrease this affect, or UAN can be injected below the soil surface. UAN is especially attractive as a source of N for sidedressing. When selecting your source of N, consider all factors. The goal is to select the cheapest source that fits within your farming operation.

April 13-20, 2004C.O.R.N Newsletter 2004-09Ohio State UniversityPatrick Lippshttp://corn.osu.edu/index.php?setissueID=32#DRelatively warm growing conditions in southern Ohio have favored the rapid development of wheat. Fields in the far south have wheat beginning the stem elongation growth stage (Feekes growth stage 6). Feekes growth stage 6 is also called the 'first joint visible' stage. You can distinguish growth stage 6 by digging up a few plants and examining their tallest tillers. Plants are made up of several tillers or stems. Pull a large tiller from each plant and strip down the several layers of leaves and leaf sheaths to expose the lower stem. A plant is considered to be at growth stage 6 when the first node is detected on the stem above the roots. This node may be from a half inch to an inch and a half above the crown of the plant. Generally plants are from about a foot to 18 inches tall at this growth stage. This is a critical growth stage for wheat because the plant changes from a vegetative growth phase to a reproductive growth phase. This also marks the time when all spring top dress fertilization should be completed so that the plant can take full advantage of the applied nitrogen. Additionally, certain herbicides must be applied before this growth stage to prevent crop injury. Check herbicide labels for growth stage application restrictions. In northern Ohio most fields are growing slowly due to the cooler night temperatures and corresponding cool soil conditions. Most fields are still in the tillering growth stages and some early planted fields are in Feekes growth stage 5 or 'upright leaf sheath' growth stage. Tillering will continue for about another week or so and fields will appear to 'fill in between the rows' due to tillering and tiller growth. Warmer temperatures later this week and into next week should promote crop development throughout the state. It is likely that most wheat in northern Ohio will reach growth stage 6 by the last week of April. Plan accordingly for top dress nitrogen and herbicide applications.