A22-UncMter Farming, Saturday, January 22, 2000 (Continued from Page A 1) dary. Manure must be recycled back into the earth for much needed plant nutrients. To ensure, however, that vegetables and fruit do not become contam inated, according to the Cornell specialist, it’s important to follow a “common-sense” ap proach to managing manure and reducing the risk. The culprit is E. coli 0157, a bacterium that causes severe ill ness, especially risky to young children and people with com promised immune systems. Fruit and vegetable consump tion has gone up 24 percent from 1970-1997. So as more fruits and vegetables are consumed, there is a disturbing upward trend in the amount of cases of food borne illness reported, noted the Cornell specialist. Increases in reported out breaks can be attributed to the technologies and information distribution capabilities of the agencies charged with tracking foodborne contamination. And foodborne illnesses are increasing globally not just in the United States. A rise in the number of salad bars in U.S. restaurants comprised 35.4 percent of the outbreaks from 1990-1998. Most of the outbreaks are associated with lettuce consumption, Ran garajan said, and sprouts. To stem the problem of food borne illness, producers can do their part to more carefully manage manure around the farm. “Learn about where the original risk comes from, de velop a plan and think about what to do,” she said. Because scientists still know little about how the foodborne disease organisms survive in the environment, there are few al ternatives. The organisms are “übiquitous,” active everywhere in the environment, she said. E.coli 0157 survives the acid conditions of the stomach and can lead to some “awful illnesses.” But the microbes behave much like other organisms in plant diseases. “Anything you do to manage the manure to protect the envi ronment,” said Rangarajan, “will also protect the crop from microbial contamination.” Growers need to keep record of manure rates, time of applica tion, methods of incorporating manure, and watch when they plant. Also, beware of what’s going on with the water. Surface water sources for irrigation can con taminate crops with harmful bacteria. The only source of water should be potable drink ing water that is regularly tested for coliform bacteria. All manure carries pathogens, so it is important to make sure the manure is incorporated into the soil and enough time goes by before planting a vegetable or fruit crop. As vegetable growers, Ran garajan told those at the meet ing to “be diligent about management of manure.” No manure should come in direct contact with produce. Flies, she said, can move off cull piles to the clean produce. Cull piles —Proper Manure Handling Key * To Controlling Foodborne Illness should be eliminated. Composting manure serves to kill much of the harmful bac teria. The heat from microbial breakdown kills the pathogens. And it’s important, the Cor nell specialist noted, to always incorporate the manure. And never, never sidedress with manure. About 120 days, at least, are required from when the manure is applied until the crop is har vested. That means manure must be applied in the fall, espe cially to early planted and har vested crops. “Keep animals out of all (packing and processing) areas as best you can,” she said. And choose a crop that is more up right to minimize the risk. Use crops that have no direct contact with the soil, including those with trellises or staking systems and plastic mulch with drip irri gation. Drip irrigation is safer because the E.coli pathogens can be carried in water. Keeping the leaves and fruit dry ensures good control. If broadcast spraying or irri gating, it is important to use pot able water if close to harvest, she noted. At harvest, according to Ran garajan, growers should pick only dry fruit, leave any fruit with fly droppings on it, use clean totes, cool the product quickly, and train workers in the importance of handwashing on a regular basis. Totes can be washed in water mixed with bleach at a rate of Vi teaspoon per five gallons or one pint per 100 gallons. Keeping the produce cool helps stem bacteria growth. At 95 degrees, one bacteria can multiply to 20 million in 6.7 hours. At 40 degrees, the same bacterial growth rate takes 16.7 days. When hand washing, special ists recommend at least 20 sec onds rubbing with soap and water. By following these proce dures, growers can stem possible outbreaks. The product is safe and producers don’t have to face the problems endured with recent outbreaks in several states. Plant Disease Powdery mildew, early blight, late blight these kinds of problems can sprout up in cu curbit and other fields. Penn State has found some significant differences in varieties and types of control of these diseases in several trials. Following management strat egies to reduce harvest loss be cause of disease is crucial, according to Dr. Alan Mac Nab, Penn State Extension, at the New Holland Vegetable Day. Mac Nab demonstrated how critical it is to watch for treat ment resistance building up in plant species. And varieties vary in their resistance to fungi. Many problems can be con trolled simply by earlier plant ing. Mac Nab noted that on early plantings, 46 days passed before early blight showed up; 30 days in mid-season; and only 14 days to the appearance of early blight late in the season. Growers should know that late blight can be “very, very Speakers at the New Holland Vegetable Day included, front from left, Dave Miller, grower; Bill Troxell, PVGA executive secretary; and Larry Yager, Penn State marketing agent. In back, Ed Herrmann, grower and Solanco Young Farm ers Association adviser; Paul Hauser, grower from Oxford; Anusuya Rangarajan, Cornell University vegetable specialist; Bob Rouse, Maryland University Wye Re search and Extension Center; and Alan Mac Nab, Penn State Extension. devastating, it can move very, very fast, and can wipe out the whole crop,” Mac Nab noted, sometimes within a two-week period. To counter the blights, pur chase disease-free tomato plants. “Destroy the potato cull pile,” he said. Blight can overwinter and spread to local fields, and you can “get in trou ble early.” And continue to rotate crops AN EGG A DAY ... Carol V. Gay Professor Of Cell Biology And Poultry Science Why does it take 24 hours, or so, for a chicken to form an egg? A short answer to this question is the complexity involved. Egg formation is a sequential, multi step process. The process begins when the ovary releases an egg yolk com plete with a cluster of embryonic cells floating on its surface; techni cally this is called the ovum, hi 15-30 minutes the funnel-shaped open end of the oviduct engulfs the yolk. I saw a movie of this engulfinent when I was a graduate student and still remember how amazing this was. How did the funnel know where the ovum was? Once engulfed, the yolk begins its journey down the oviduct, a tube that is 16-18 inches long. Much of the oviduct is comprised of a region, called the magnum that manufactures and secretes proteins to form the egg white, mainly albu men and several other proteins. The oviduct wall is muscular and so can move the ovum along by a to stem disease. Vegetable Growers Association Bill Troxell, executive secre tary of the Pennsylvania Vegeta ble Growers Association (PVGA), spoke about the work of the association in helping to fund research, its work on pro moting the industry, and about the Mid-Atlantic Fruit and Veg etable Convention. The PVGA helped fund 14 gentle squeezing, pulsating action that rolls the yolk in a slow prog ressive spiral. The result is that by the time the yolk passes through the magnum it has become coated with egg white and has taken on the characteristic egg shape. Transit time through the magnum, which is about 13 inches long, is 2-3 horns. The next segment of die oviduct is called die isthmus; it is quite short, about 1 inch in length, but transit time is 1-2 hours. The isthmus also secretes proteins, but these proteins form a tough highly cross-linked membrane, known as the shell membrane, on the egg white surface. This membrane will serve as die foundation for eggs hell formation. Finally, the now well-defined egg enters the last region of the oviduct, the shell gland. The egg spends 20-26 hours in this final chamber. In the first few minutes, a dilute salt solution diffuses into the egg white, a process called plump ing, causing the egg to swell to its full size. Then, the eggshell is formed as calcium carbonate crys tals precipitate onto die shell membrane. The finishing touches of egg formation include secretion of pig ment and the water impervious different projects. It also helped fund many promotional efforts statewide, along with money from the Pennsylvania Depart ment of Agriculture. Through the PDA, PVGA helped erect 23 billboards. The PDA erected 70 more billboards with the “Pennsylvania Pro duce: Simply Delicious” logo. Press releases, detailing the work of the PVGA, reached 2.4 million readers. cuticle. The egg is laid about a day after tbc yolk began its journey in the early morning hours of the pre vious day. As mentioned, there arc two time-consuming steps in the egg forming process: laying down die egg white and forming the calci fied shell. Could these processes be forced to occur more rapidly to increase egg production? This is doubtful, because the structures that form both egg white and eggs hell have to be replenished. Penn ing egg white protein requires delivery of die protein building blocks, die amino acids, to the tissue that then builds new protein by adding amino acids one fay one to the growing ends of die protein molecules. Amassing a large vol ume of protein requires time. Likewise, replenishing the sour ce of eggshell calcium in the medullary bone is also time con suming. The laying hen wastes no time in replenishing these stores. While the shell is being formed, new albumen is synthesized and conversely, while albumen is formed, calcium stores are replenished. Egg formation is a complex pro cess and is tightly orchestrated by many kinds of neuto-endocrine controls. Disturbances to the control mechanisms result in cessation of laying which can take many days to recover. /Sk
Significant historical Pennsylvania newspapers