Page B—Corn Talk, Lancaater Farming, Saturday, January 29, 2000 In 2001, Bt Corn Technology Will Provide Rootworm Control At Root Zone ANDY ANDREWS Lancaster Farming Staff LANDISVILLE (Lancaster Co.) Beginning in 2001, about 1 percent of the com acreage in the U.S. will be com prised of Bt com that fights com rootworm where it matters most at the roots. The Bt variety, marketed under unspecified variety names by a major seed produc er, will be another transgenic com tool to fight destructive crop pests. But producers need to keep in mind that transgenic com coming out may not pro tect against black cutworm and other pests, according to Den nis Calvin, Penn State entomologist. Calvin spoke to about two dozen crop management exper ts and industry representatives in mid-December at the first of a Penn State-sponsored two day Capitol Region Crop Insect and Disease Management School at the Penn State Exten sion Southeast Regional Labor atory near Landisville. If com producers are to use the new Bt varieties, it’s possi ble they’ll need other insect type controls using standard chemical treatments or in com bination with an overall indus try approved integrated pest management (IPM) program. Today’s varieties of Bt com do not control black cutworm and provide little control of stalk borer, fall armyworm, or com earworm. The new com rootworm Bt “stacked” varieties, noted Cal vin, would be expressed at the larvae stage of the com rootworm. Penn Stale tested a variety of com rootworm Bt this past year. Unfortunately the drought wiped out the rootworm popu lation, though “what we did have looked good,” said Cal vin. The control was the same as other standard soil insecti cide programs, though using the Bt type controls could push costs slightly higher. It’s not clear yet what the premium costs could be. More woric is necessary, he noted, at the Penn State Rockspring research farm and at a private farm where test ing is under way. Silage Roller Mill A specialized mill designed for silage & high moisture grains, Diameter 10”x20” long Rolls up to 600 bushels an hour of silage & gram F.M.1.-Feedmobile 727 Furnace Hills Pike, Lititz, PA 17543 717-626-2680 Calvin and other crop man agement experts provided an introduction to the philosophy of pest management through IPM at the school. The use of Bt com as part of a program has raised some con cerns over the Monarch butterf ly controversy. Lab studies indicated that it is possible the pollen from Bt com can kill Monarch butterflies, and indus try and academia has been under heavy criticism from the public. Calvin said he spent time at two conferences this fall, including two days in Chicago, reviewing the Bt and Monarch butterfly controversy. Appa rently, the Bt 176 type can have a 10-fold expression in the com pollen, yet only 1-2 percent of the Bt com planted uses this type. The Bt 176 type only expresses up to eight yards from the edge of a field. More field studies of the effects of the Bt com on the butterflies may be needed. Favorite pollen-feeding plant species for the Monarchs are milkweed and dogbane. In lowa and Illinois, milkweed grows on the roadways. A milk weed variety in Kansas, Blue Vine, is a really good host for the butteries. Much of the information about the potential toxicity of Bt to the butterflies has been “taken out of context to stir something up,” Calvin noted. But the controversy has allow ed the industry to step back and reexamine other, more “holis tic” ways, friendly to the envi ronment. to control pests. Calvin referred to the prog rams outlined in the Penn State issued Field Crop IPM Guide, available for $75 from the Capitol Region Extension Agronomy Team. More detail about the program is available by contacting Del Voight at the Lebanon extension office at (717) 270-4391. For now, growers have <|si) <@> (®g) (6SI) Grain Bins Grain Dryers (pSP Elevators <@> (IJSI) Augers from (|SD Westfield (R SI) From ZZ and SONES GRAIN SYSTEMS (GSI) Hutchison Muncy, PA (570) 584-2282 Several crop insect and disease management experts spoke to shout two dozen crop msnagement experts and industry representatives in mid- December at the first of s Penn State-sponsored two-day Capitol Region Crop Insect and Disease Management School at the Penn State Extension South east Regional Laboratory near Landisville. From left, looking over a predator beetle model, John Ayers, Del Voight, and Dennis Calvin. embraced the Bt com, which uses a natural biological control embedded in com genes, to control the European com bor er. The industry has “made a lot of strides in the genetic method of pest management,” said Cal vin. But with those advances have come new strategies to ensure its long-term effective ness and viability. IPM emphasizes taking a look at the crop grown, the rota tion, the cultural practices, the soil and environment types, consistent scouting, and under standing effective timing and application of pesticides. Pro ducers must look at the eco nomics of the use of different technologies to see if they’ll be useful. Finding that "economic threshold,” Calvin noted, is key. The issue is, “when do I treat to get the most effective control?” Fact is, the economic thresholds are “not based on as much science as we think,” Cal vin noted. GSI For example, for the com leaf aphid, the threshold is 25 aphids per foot of row in the fall, or 100 aphids per foot of row in the spring. To fmd those thresholds, a computer spreadsheet program was shown at the school. In the past, to control the com borer, no economic treat ments were available in the reg ion. Only a small percentage of growers could justify using standard treatments. But with Bt com, the borer became an economic concern, now that technology has arisen to treat it. according to Calvin. “This changed the econom ics of managing the pest, because we have a tool that does a much better job,” noted the Penn State entomologist. Bt com offers almost complete control of the pest under good growing conditions. Calvin noted several resour ces for producers. If there is one book that offers a complete index of information from tden- tification to insect biology, he recommended the reference, “Handbook of Com Insects,” available from the Entomologi cal Society of America (Land ham. Md., 1999, 174 pp., $35. ISBN 0-938522-76-0, 301-731-4535). For com refer ence, if there was one book to identify insect pests, “this would be it,” he said. For soybeans, Calvin recom mended die “Handbook of Soy bean Pest Insects,” available from the society (1994,142 pp., $25, ISBN 0-938522-29-9). r Penn State has its own IPM’ Website at www.fra.cas.psu.edu/ Calvin also recommends the “ Penn State Agronomy Guide,” also available on the Web at http://agguide.agronomy.psu.c du/ Del Voight, crop team mem ber and Lebanon extension agent, and John Ayers, Penn State plant pathologist, reviewed ways to diagnose dis (Tum to Pago 10) Stirring Machines and Grain Cleaners from Sukup and DMC m> Bucket Elevators From Lampton