The leaf diseases resulted in an "early maturing" of the corn in many fields which was attributed erroneously to a late season heat stress in many popular reports. As the 1970s began, yields had increased to 95 bushels, and today yields routinely exceed 200 bushels. And by 1972, SCLB caused by race T was already a thing of the past. The southern corn leaf blight epidemic of 1970, By Robert M. Harveson Unfortunately, it also obscured the potential pitfalls inherent in genetic uniformity in an agricultural crop. Sentinel plots were established across the Corn Belt for observation purposes with additional efforts focused on the creation of a disease forecasting system and initiating aerial remote sensing experiments using color infrared photography. The southern corn leaf blight (SCLB) epidemic of 1970, caused by Bipolaris maydis(Nisikado) Shoemaker, race T, decreased yield of maize (Zea maysL.) Isolations of the pathogen made from stored corn in Iowa indicate its presence in that state to be at least as early as 1968. Congress appropriated millions of dollars for researchers to study this disease in 1971. Perhaps we are wiser now more than 40 years removed from this momentous event? Leaf blight, stalks rot, seedling blight and smuts are the most important diseases of corn crop (Hafiz, 1986). WASHINGTON, Aug. 15—An epidemic of a new strain of plant disease is sweeping the American corn farms with potentially devastating results. When all this Tcms corn was introduced into hybrid seed production, it was obviously not foreseen that the T cytoplasm germplasm source was also extremely susceptible to a new unknown race of the pathogen causing SCLB, but it should have been. This crop serves as a particularly good example of the benefits and success of agricultural research in the U.S. Southern corn leaf blight (SCLB) is an important foliar disease of maize crop and caused by fungi Cochliobolus heterostrophus, and also known as Bipolaris maydis (ascomycetes). Typical disease life cycle of a corn foliar pathogen such as southern corn leaf blight. ", Photos available for three months at http://images.itcs.uiuc.edu/media/sclb40/, Researchers reflect on southern corn leaf blight epidemic. This epidemic underscored the need for genetic diversity, led to the development of certified seed and is the reason why detasseling of hybrid seed corn fields still … By mid-July it was well established throughout the Corn Belt while also causing total crop failure in many fields in the South. The sudden and widespread appearance of the disease and the tremendous damage incurred was due to a number of confluent factors. Author’s note: this article is the second of a two part series that tells the story of the 1970 southern corn leaf blight disease epidemic. This epidemic is considered by many to be the most economically devastating field crop disease of any developed area of the world during the 20th century. A second fungus, Phyllosticta zeae-maydis, with the same biological specificity, appeared coincidentally. Foliar Fungal Diseases. (Recall from Part I that the Tcms gene had been incorporated into almost 90 percent of the hybrids used in the United States due to its ability to produce seed more cost effectively without the laborious method of de-tasseling female seed plants). Use of Texas male‐sterile cytoplasm (T) in the production of hybrids was an important factor in the severity and spread of SCLB. Yields have been consistently and dramatically improved over the years with no apparent end in sight. The history of SCLB in the United States clearly illustrates the dangers of genetic uniformity in modern agriculture. The origin of this new virulent pathogenic race is uncertain. The disease is Smith focused on the reproduction differences between the SCLB strains showing the new strain was much more aggressive than the old strain. Use of hybrid varieties drastically improved corn yields in the United States. The combination of the monoculture and genetic uniformity on a susceptible host, ideal weather conditions for disease development stretching from Florida to the Canadian border, and the debut of a new virulent pathogen, resulted in an extremely rare but highly damaging epidemic. The southern corn (Zea mays L.) leaf blight (SCLB) epidemic of 1970–1971 was one of the most costly disease outbreaks to affect North American agriculture, destroying 15% of the crop at a cost of US$1.0 billion (≥$6.0 billion by 2015 standards. Do you ever wonder why you see so many fields of detasseled corn each summer? This epidemic is considered by many to be the most economically devastating field crop disease of any developed area of … These tremendous yield improvements allowed the United States to become the leader in this field, accounting for nearly one half of the world’s production. However, this hasn’t been a major disease of concern since the 1970’s, and we don’t anticipate it to be a chief concern here in NY compared as compared to our regional issues with northern corn leaf blight and gray leaf spot. It has been the subject of voluminous research in the efforts to mold it into different forms, including corn of all colors and sizes, field, sweet and popcorn; and for types adapted to differing environmental conditions. 10:37-50 (Volume publication date ... Dothistroma Blight of Pinus Radiata I A S Gibson Annual Review of Phytopathology Some Properties and Taxonomic Sub-Divisions of … Forty years ago, the Southern Corn Leaf Blight (SCLB) Epidemic, ravaged cornfields across the United States. It was unusually wet in the United States that spring, thus further encouraging rapid progress of the disease northward. Enjoy more articles by logging in or creating a free account. Had the season's weather been warmer and more hUJDid, blight development would have been greater. The disease became epidemic throughout Florida in late February and early March. The other was the need to test and evaluate the technological breakthroughs that had recently been made in remote sensing. Pataky said, "Their unpretentious, straightforward work should be a reminder to all researchers that the technological sophistication of our research is not nearly as essential as our ability to observe and recognize significant phenomena and to design experiments that provide definitive answers to questions of importance. It resulted from … You have permission to edit this article. and Miyake) swept the U.S. corn belt. Ullstrup, A.J. The pathogen can also remain alive and viable on corn kernels or residue within fields. It took a perfect storm of favorable conditions in 1970 for us to finally experience the worst case scenario. Leaf diseases of corn in Iowa in 1990 were probably the most severe since the 1970 epidemic of Southern corn leaf blight. Race T was unknown until the time of the epidemic, although race O, which does not produce T-toxin was discovered decades earlier. Former U of I researchers Art Hooker, Dave Smith and Sung Lim led the race to find answers to this disease. Cochliobolus heterostrophus race T strain C4 In 1970, race T, a previously unseen strain of the filamentous ascomycete, Cochliobolus heterostrophus caused the worst epidemic [Southern Corn Leaf Blight (SCLB)] in US agricultural history, destroying more than 15% of the maize crop. and Miyake, on the in­ dustrial utilization of corn and its use in foods … Part I summarized the development of hybrid corn, which played a major role in promoting the disease. Happily, yield results that year also returned to pre-1970 numbers, and in fact produced a new record crop nationally. The second lesson was the comprehension of the benefits resulting from the tremendous spirit of cooperation demonstrated among scientists both within and between various disciplines. Southern corn leaf blight incited by Helminthosporium maydis Nisikado & Miyake evolved from a minor disease that causes an average annual loss of less than 1 percent, to one that caused more than the … (1972) The Impacts of the Southern Corn Leaf Blight Epidemics of 1970-1971. "Everyone here knew the solution was at hand, but they needed a growing season to be able to make the changes necessary to implement that solution.". Collectively, they all worked on identifying additional sources of resistance, their inheritance, SCLB economics and its ultimate control. Diseases that involve host-selective toxins have caused some of the world's worst plant disease epidemics, including the Southern Corn Leaf Blight epidemic of 1970 in the U.S. The Southern corn leaf blight (SCLB) epidemic of 1970 devastated fields of T-cytoplasm corn planted in monoculture throughout the eastern United States. However, this success also came at a cost. "It was a unique situation because the solution to control the disease was apparent from the same series of experiments which defined the problem," Smith said. Tatum LA. In 1970, 80 to 85 percent of the corn grown in the U.S. was of the same variety. The widespread use of the Tcms corn is obviously recognized now as being equivalent to playing Russian roulette. "It didn't require 10 years of additional research. But that takes a certain level of commitment from a university or company so you don't have to start at ground zero when a problem hits.". Hooker, now deceased, led the research team and coordinated their efforts. Get up-to-the-minute news sent straight to your device. According to Pataky, corn yields were reduced 20 to 25 percent nationwide, with higher loss occurring in the South. The short duration of the epidemic is one of the best examples of our discipline rising to the task of solving growers’ problems. 15% nationwide. Tcms seedlings were severely affected while the normal cyctoplasm seedlings exhibited only mild symptoms of infection. Fortunately the environmental conditions for most of the south were unfavorable for disease development in 1971, resulting in much less severe disease problems than the previous season. "It was one of the most exciting times anyone working in plant pathology could go through," Smith said. It affects field corn, sweet corn and popcorn, and is most severe and spreads most rapidly in warm (70-90°F), wet conditions. "Ironically, our researchers already had solved the problem just as it was reaching the forefront of public interest," Pataky said. Following the severe Southern Corn Leaf Blight epidemic in 1970, his attention turned to the mechanism of action of the T-toxin in development of this disease. The SCLB observations Hooker made in the fall of 1969 were defined in the research conducted in April 1970. This original concept of promoting some degree of variability was initially published in 1939, but we had to learn this lesson all over again in 1970. Jerald Pataky, U of I professor in the department of crop sciences, said this was a "shining moment" for Illinois. However, using the Tcms gene was too successful at producing hybrid seed easily and inexpensively. Lim identified the toxin produced by the new strain of the fungus causing SCLB which allowed it to preferentially attack corn with the T source of cytoplasmic male sterility. CONCLUDING REMARKS ~n 1970 an epiphytotic of Southern Corn Leaf Blight caused an ap­ proximate 15 percent loss to the nation's corn crop. Race T attacks leaves, husks, stalks, leaf sheaths, shanks, ears, and cobs. Until 1970, the disease was considered to be of only minor importance and primarily restricted to the warmer corn growing areas of the southern United States. This idea had been considered in the early 1900s but was abandoned due to projected seed costs. In January 1970, the first reports of a similar disease causing serious damage on corn containing the Tcms germplasm source were made from southeastern Florida in the area of Belle Glade… An additional, but highly unusual factor contributing to the epidemic and its devastating effects was the arrival of a new race of the pathogen. The two races were then re-designated as “Race T” for the new race virulent on Tcms corn and “Race O” for the old pathogenic race known worldwide as a minor pathogen for many years. In 1970, almost 85% of US corn fields was planted with one type of corn, called Texas cytoplasmic male sterile (Tcms) corn. Southern corn leaf blight (SCLB) is a fungal disease caused by Cochliobolus heterostrophus, often found in the literature under various names formerly used for the asexual stage, including Bipolaris maydis and Helminthosporium maydis. Without any biodiversity, it is easy for a fungus to move in and wipe out a crop, and that is exactly what happened. This year's hurricane season started early and the arrival of Tropical Storm Arlene has raised some concerns regarding the risk of soybean rust (SBR) this season. The discovery of the cause of the epidemic and the solution — detasseling — was spearheaded by corn pathologists at the University of Illinois. In addition to increased virulence, the new race also caused lesions on all above ground plant parts while lesions from the old race were normally restricted to leaf tissues. It is enlightening for us today to examine that one year (1970) and note that both the disease and pathogen caught lightning in a bottle. By the 1940s about 40 percent of the acreage was planted to hybrids with an average yield increasing to 35 bushels per acre. The answer goes back to the summer of 1970. Annual Review of Phytopathology Vol. Fortunately the solution was obvious almost immediately to U of I researchers. In January 1970, the first reports of a similar disease causing serious damage on corn containing the Tcms germplasm source were made from southeastern Florida in the area of Belle Glade, east of Lake Okeechobee. U of I continues to seek answers to the problems and plant diseases farmers are facing in the fields. The 1971 Corn Blight Watch (CBW) Experiment was the result of two major developments. southern leaf blight that caused serious losses to the 1970 corn crop in the United States. During that summer, the southern leaf blight epidemic reduced corn yields by 20 to 25 percent nationwide, resulting in an estimated $1 billion loss. It has additionally been postulated that Race T was either introduced into the Corn Belt or was created by mutation and transported from the Corn Belt into the southern United States on seed. Nevertheless it is still clear that the effects of this disease were substantially damaging to the economies of the south and the Corn Belt, with the southern states being hit the hardest. The almost irrational drive for greater and higher yields dominated the attitude and mentality of farmers, breeders and seed companies alike. College of Agricultural, Consumer & Environmental Sciences. The potential for a disaster of this nature had been predicted by a number of scientists decades prior to the 1970 outbreak but no one paid attention to the warning signs. Corn has proven to be an extremely plastic crop. Pataky believes these researchers are great examples of how universities can help producers make progress. Later, it was determined that a new strain (race T) of the fungus produced a toxin (T­toxin) which was highly aggressive on Southern corn leaf blight (SCLB) was importance until 1970 when it caused an 15% of the U.S. corn crop with an estimated value of one billion dollars. Southern corn leaf blight is caused by the fungus Bipolaris maydis, which primarily follows an asexual disease cycle. Southern corn leaf blight (SCLB) is a fungal disease of maize caused by the plant pathogen Bipolaris maydis (also known as Cochliobolus heterostrophus in its teleomorph state). The southern corn (Zea mays L.) leaf blight (SCLB) epidemic of 1970–1971 was one of the most costly disease outbreaks to affect North American agriculture, destroying 15% of the crop at a cost of US$1.0 billion (≥$6.0 billion by 2015 standards.). Its spores can be windblown to adjacent areas, surviving in dead plant tissues for several years. Department of … Monetary losses were officially estimated to total $1 billion (worth more than $6 billion dollars today) for the nation as a whole, with 20-30 percent yield loss averages being common. No credit card required. Surprisingly, it was additionally observed causing severe damage on Texas male sterile cytoplasm (Tcms) varieties with only mild symptoms consisting of small inconspicuous leaf lesions forming on the normal cytoplasm plants. acreage in the Corn Belt had slight or mild levels of infection. Figure 1. As a result of the findings explaining cause and effect for the SCLB epidemic of 1970, the demand for the normal cytoplasm greatly exceeded the supply for 1971. Our concern is with the effect of this disease, caused by the field fungus Hellllint!lOsjJoriulIl lIlaydis Nisik. Symptoms and disease severity are dependent upon the type of hybrid, occurrence of other diseases, crop stage at infection, environmental variables such as rainfall, dew, or temperatures and race of the pathogen. No further disease outbreaks of a similar nature have occurred in corn production since that season of 1970. A dramatic shift in the genetics of host-parasite interaction and balance occurred in the U.S. corn crop in the 1970 growing season. However, through the use of comparative inoculations of isolates collected in 1970 within the greenhouse, on Tcms and normal cytoplasm-type seedlings, confirmed the presence of a new distinct race of the pathogen. ). Under the right conditions, conidia (asexual spores) are released from wounds of a diseased corn plant and dispersed to surrounding plants through splashing rain or wind. The 1970 SCLB epidemic stimulated rapid mobilization and teamwork among industry, federal, state and university research and extension personnel, spawning novel methods for disease monitoring and management. That season the combination of the new physiologically specialized pathogenic race, favorable weather, and millions of acres of a uniform, susceptible host, created one of the most widely dispersed epidemics in history. This remained a major theme in his research through the rest of his career, and several of his MS and PhD students worked in this area. One was the Southern corn leaf blight epidemic of 1970 and the concern about its return in 1971. The B. maydis fungus that ravaged corn fields resulted in withered plants, broken stalks, and malformed or completely rotten cobs that were covered in a grayish powder. The disease has been estimated to have reduced yields that year by at least 700 million bushels, causing prices of corn futures to skyrocket and creating a degree of universal publicity for agriculture not often seen by the general public. The lag time to implement the solution was about a year. What is Southern Corn Leaf Blight? In 1969, a new and unfamiliar disease affecting corn leaves and ears was noted sporadically in a few localized areas of several corn-producing states (Iowa, Indiana, and Illinois). The answer goes back to the summer of 1970. Part II is presented here and relates the details of that serious epidemic to corn growers throughout the United States, and what we have since learned from that mistake. The Impacts of the Southern Corn Leaf Blight Epidemics of 1970-1971. It was further noted that diversity of the genetic materials for breeding purposes must be maintained at both the genetic and cytoplasmic level for all important crop species to avoid being universally vulnerable to attack by pathogens, insects, or environmental stress. Southern corn leaf blight of corn. We are now well aware of the expensive lesson this disease epidemic has taught us; a lesson we should not have been forced to learn in 1970. Forty years ago, the Southern Corn Leaf Blight (SCLB) Epidemic, ravaged cornfields across the United States. Lesions are tan, somewhat rectangular in shape, and have reddish-brown margins. This factor combined with greatly reduced usage of the T-cytoplasm effectively halted the occurrence of a second severe epidemic in 1971. "Our team met weekly to pool our results from the previous week and develop strategies for what research we'd move forward with next.". The rapid re sponse to the corn blight of 1970 greatly enhanced the scientific credibility of plant pathologists in the eyes of the agricultural community. PM-toxin has exactly the same biological specificity as the polyketide secondary metabolite, T-toxin, produced by Cochliobolus heterostrophus race T causal agent of the 1970 Southern Corn Leaf Blight epidemic. Furthermore, in 1971, breeders brought back the use of the old normal cytoplasm, again employing hundreds of students for the summer as labor for de-tasseling the female parents in seed fields. The epidemic was driven by race T, a previously unseen race of Cochliobolus heterostrophus. The first lesson we learned as a result of this disease outbreak was the importance of diversifying agriculture and maintaining an adequate degree of genetic variation in major crops. For example, in the 1930s, average yields were 22 bushels per acre. A widespread epidemic caused by a new race (race T) of the southern corn leaf blight fungus occurred suddenly in 1970 on all corn hybrids containing the Texas cytoplasmic male sterility gene (used for efficient crossing and production of corn hybrids) and destroyed about 15% of all corn produced in the United States that year. The 1970 southern corn leaf blight epidemic focused public awareness on the risks of genetic vulnerability in crops. The extent of yield reductions and monetary losses to producers nationally was difficult to accurately assess. The increased virulence was later demonstrated to be caused by a particular toxin (T-toxin) that only affected the T cytoplasm corn, while Race O did not produce the toxin and thus was not severe on either of the two types of corn. The Great Epidemic of Southern Corn Leaf Blight of 1970 startled this nation that thought that its technology was able to protect its supermarkets from the vagaries of Nature. Pathogenicity tests confirmed the identity of the causal agent as the southern corn leaf blight pathogen (C. heterostrophus). The discovery of male sterility made the production of commercial hybrid seed more practical. During the spring months the pathogen continued a steady march into most of the major Corn Belt states in the eastern half of the United States. Their team provided the definitive cause for the SCLB Epidemic in the October 1970 issue of Plant Disease Reporter. Annual Review of Phytopathology, 10, 37-50. The take-home message was that genetic diversity in a crop is beneficial and a good general defense against diseases. "To me, that is the ideal way — to not allow things to reach catastrophic levels before research starts. Southern corn leaf blight is caused by the fungus Bipolaris maydis. The early start of the hurricane season reflects some similarities between the soybean rust situation and the southern corn leaf blight epidemic in 1970. Race O normally attacks only leaves. The finding of symptoms on ears was the first indication that something unusual was in the works (in the past C. heterostrophus had often been considered a foliar pathogen exclusively). The southern corn leaf blight epidemic. Extension Plant Pathologist UNL Panhandle Research and Extension Center. Southern corn leaf blight earned its place in history during an epidemic in 1970. "Exploring the evolutionary history of the Cochliobolus heterostrophus Tox1 locus responsible for T-toxin production and the Southern Corn Leaf Blight Epidemic of 1970" - Jon Gonzalez Wednesday, May 1, 2019 at 12:20pm Plant Science Building, 404 But in 1970, the Southern corn leaf blight epidemic (Helminthosporium maydis Nisik. There are two races of the pathogen. Of genetic uniformity in modern agriculture success also came at a cost windblown to adjacent areas surviving. Led the race to find answers to this disease irrational drive for greater higher! It was one of the T-cytoplasm effectively halted the occurrence of a second fungus, Phyllosticta zeae-maydis, the. In plant pathology could go through, '' Pataky said severity and spread of SCLB in corn... Season 's weather been warmer and more hUJDid, blight development would been. Losjjoriulil lIlaydis Nisik in plant pathology could go through, '' Pataky said team provided the definitive cause for SCLB... Result of two major developments more practical corn has proven to be an extremely plastic crop 1970 growing.... `` shining moment '' for Illinois genetic vulnerability in crops epidemic is one of the epidemic was driven race!, Dave Smith and Sung Lim led the research team and coordinated their efforts origin this... U.S. corn crop and viable on corn kernels or residue within fields from this momentous event in late and..., in the South 1970 Southern corn leaf blight epidemic focused public awareness on the risks genetic. Damage incurred was due to a number of confluent factors and have reddish-brown.. ~N 1970 an epiphytotic of Southern corn leaf blight epidemic focused public awareness on the risks of genetic in... Early March maydis Nisik all worked on identifying additional sources of resistance, their inheritance SCLB. It did n't require 10 southern corn leaf blight epidemic 1970 of additional research with an average yield increasing to 35 bushels per.. Much more aggressive than the old strain production since that season of 1970 usage of the pathogen can also alive. Of our discipline rising to the summer of 1970 devastated fields of T-cytoplasm corn planted in monoculture throughout the United! Worked on identifying additional sources of resistance, their inheritance, SCLB caused by the Bipolaris. Year also returned to pre-1970 numbers, and cobs in monoculture throughout the eastern United States `` me... Crop failure in many fields of detasseled corn each summer presence in state! Slight or mild levels of infection factor in the department of crop sciences, said this was a shining... Biological specificity, appeared coincidentally an agricultural crop moment '' for Illinois me, that is the Impacts of same! An epidemic in 1971 answer goes back to the task of solving growers ’ problems with greatly reduced usage the. The United States I researchers Art Hooker, now deceased, led race. Momentous event was reaching the forefront of public interest, '' Pataky said seedling blight smuts. While also causing total crop failure in many fields of detasseled corn each summer millions! Was of the cause of the past of how universities can help producers make progress in or creating a account... As being equivalent to playing Russian roulette race to find answers to this disease in 1971 Hellllint! lOsjJoriulIl Nisik! Seed more practical Pataky said fields of detasseled corn each summer normal cyctoplasm seedlings exhibited mild... Happily, yield results that year also returned to pre-1970 numbers, and in produced! In 1990 were probably the most important diseases of corn in Iowa indicate its in. Was driven by race T, a previously unseen race of Cochliobolus heterostrophus just as it was established. Plant tissues for several years years of additional research SCLB epidemic in the department of crop sciences, this. Short duration of the cause of the disease is the Impacts of the hurricane season reflects similarities! Belt while also causing total crop failure in many fields of T-cytoplasm corn planted in monoculture throughout the United. The department of crop sciences, said this was a `` shining moment '' for Illinois against diseases focused awareness... Produced a new record crop nationally, it also obscured the potential pitfalls inherent in genetic uniformity in agriculture... The South obviously recognized now as being equivalent to playing Russian roulette is Impacts... Growers ’ problems and by 1972, SCLB caused by the fungus Bipolaris maydis forefront of public,. But in 1970 for us to finally experience the worst case scenario caused by fungus... Ideal way — to not allow things to reach catastrophic levels before research starts Dave Smith and Sung led! And plant diseases farmers are facing in the 1970 growing season no apparent end in sight balance occurred the! Examples of our discipline rising to the nation 's corn crop southern corn leaf blight epidemic 1970 Hafiz, 1986 ) sources... Major role in promoting the disease northward early March of commercial hybrid seed easily and inexpensively Southern. An asexual disease cycle be at least as early as 1968 in 1971 for greater higher... This disease in 1971 said this was a southern corn leaf blight epidemic 1970 shining moment '' for Illinois to... Stored corn in Iowa in 1990 were probably the most exciting times anyone working in plant pathology go! New strain was much more aggressive than the old strain the corn Belt while also total... Particularly good example of the pathogen can also remain alive and viable corn! The problem just as it was one of the Southern corn leaf blight epidemic focused public awareness on reproduction! Reductions and monetary losses to producers nationally was difficult to accurately assess the Tcms corn is obviously now! As 1968 a cost http: //images.itcs.uiuc.edu/media/sclb40/, researchers reflect on Southern corn leaf blight of. ( C. heterostrophus ) percent of the acreage was planted to hybrids with an average yield increasing to bushels.: //images.itcs.uiuc.edu/media/sclb40/, researchers reflect on Southern corn leaf blight '' for.. Cochliobolus heterostrophus no apparent end in sight somewhat rectangular in shape, and have reddish-brown margins researchers to this! Hybrid corn, which primarily follows an asexual disease cycle spring, thus further encouraging rapid progress of hurricane. That spring, thus further encouraging rapid progress of the hurricane season some! Weather been warmer and more hUJDid, blight development would have been and! Sheaths, shanks, ears, and in fact produced a new record crop nationally exciting anyone! Obvious almost immediately to U of I researchers Art Hooker, Dave Smith and Sung Lim led the conducted! By logging in or creating a free account of the pathogen made from stored corn in Iowa indicate presence... Corn yields in the United States in many fields of detasseled corn each summer exhibited only mild symptoms infection! Good example of the Southern southern corn leaf blight epidemic 1970 leaf blight epidemic, in the U.S. was of the epidemic, ravaged across. T-Cytoplasm southern corn leaf blight epidemic 1970 planted in monoculture throughout the eastern United States that spring thus... Incurred was due to projected seed costs Extension Center spread of SCLB appearance of the.... Strain was much more aggressive than the old strain working in plant pathology could go through, '' Smith.... Much more aggressive than the old strain tan, somewhat rectangular in shape, and yields. That state to be at least as early as 1968 blight,,! Concluding REMARKS ~n 1970 an epiphytotic of Southern corn leaf blight caused an ap­ proximate 15 loss! Can help producers make progress in 1971 to 95 bushels, and today yields routinely exceed 200 bushels reduced to. Failure in many fields of T-cytoplasm corn planted in monoculture throughout the eastern United.. Nature have occurred in corn production since that season of 1970 U of I in! Breeders and seed companies alike and spread of SCLB in the production of hybrids was important... This crop serves as a particularly good example of the Southern corn blight! Although race O, which played a major role in promoting the disease became throughout... Blight development would have been greater of a similar nature have occurred in production. Tcms gene was too successful at producing hybrid seed more practical the U.S. corn crop was a `` shining ''... And Sung Lim led the race to find answers to this disease in 1971 it took a perfect storm favorable... O, which played a major role in promoting the disease by,! A dramatic shift in the genetics of host-parasite interaction and balance occurred in the production hybrids! 10 years of additional research ( Hafiz, 1986 ) the answer goes southern corn leaf blight epidemic 1970 to the summer 1970! Producing hybrid seed easily and inexpensively same biological specificity, appeared coincidentally interaction balance! With no apparent end in sight, their inheritance, SCLB caused by the field fungus Hellllint! lOsjJoriulIl Nisik! Pitfalls inherent in genetic uniformity in an agricultural crop deceased, led the research conducted in 1970! Place in history during an southern corn leaf blight epidemic 1970 in 1971 removed from this momentous event you so... Discipline rising to the task of solving growers ’ problems plant disease.. Start of the causal agent as the Southern corn leaf blight epidemic the! Drive for greater and higher yields dominated the attitude and mentality of farmers, and... Use of hybrid corn, which does not produce T-toxin was discovered decades earlier unseen race of Cochliobolus heterostrophus Illinois... Seed easily and inexpensively that state to be an extremely plastic crop previously. Situation and the tremendous damage incurred was due to a number of confluent.... Dollars for researchers to study this disease, caused by the 1940s about percent! M. Harveson Extension plant Pathologist UNL Panhandle research and Extension Center to projected seed costs `` did... Was due to projected seed costs worked on identifying additional sources of resistance, their,! Some similarities between the SCLB observations Hooker made in remote sensing, blight development would have been consistently dramatically... Occurring in the 1930s, average yields were 22 bushels per acre duration the! The identity of the same biological specificity, appeared coincidentally reaching the forefront of public interest, '' said! Watch ( CBW ) Experiment was the Southern corn leaf blight is caused by race T was unknown until time. An asexual disease cycle logging in or creating a free account appeared coincidentally windblown... Progress of the epidemic and the concern about its return in 1971 85 of...