Birds Prefer Conventionally Grown Wheat Due to Higher Protein Levels

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There is considerable debate about the merits of consuming organic foods. Some studies have found that certain animal species prefer to eat organically-grown crops. However, these results have been challenged by a recent study…

“One key reason why consumers buy organic food is because they consider it to be better for human and animal health. Reviews comparing organic and conventional food have stated that organic food is preferred by bird and mammals in choice tests. This study shows the opposite result – that captive birds in the laboratory and wild garden birds both consumed more conventional than organic wheat when given free choice. There was a lag in preference formation during which time birds learnt to distinguish between the two food types, which is likely to explain why the present results differ from those of previous studies.”

“A further experiment confirmed that, of 16 potential causal factors, detection by birds of consistently higher levels of protein in conventional seeds (a common difference between many organic and conventional foodstuffs) is the likely mechanism behind this pattern. The results of this study suggest that the current dogma that organic food is preferred to conventional food may not always be true, which is of considerable importance for consumer perceptions of organically grown food.”

Authors: A.J. McKenzie and M.J. Whittingham
Affiliation: School of Biology, Newcastle University, Newcastle upon Tyne, UK
Title: Birds select conventional over organic wheat when given free choice.
Publication: Journal of the Science of Food and Agriculture. (2010) 90:1861-1869.

30 Years Ago, We Knew Herbicides Increased Canadian Wheat Yields

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Canada ranks sixth in the world in wheat production and is the second largest exporter of wheat with 70% of its production exported annually. Since 1960, wheat yields have doubled in Canada. A group of Canadian researchers set out to identify the key factors accounting for the yield increase…

From abstract: “Therefore, we suggest that chemical weed control was the main contributing factor to the yield increases. This control has resulted not only in reduced competition from weeds, but also in better seedbed moisture because fewer cultivations are needed in the spring. “

“Because of the ability to control weeds with chemicals, it is now also possible to seed shallowly into a moist seedbed immediately after one cultivation since numerous spring cultivations with a resultant loss of valuable soil moisture are no longer necessary to eliminate germinating seeds. Fertilizer application and improved cultivars have also contributed, but to a lesser degree, to the yield increases.”

Authors: S. Freyman et al.
Affiliation: Agriculture Canada, Lethbridge, Alberta, Canada
Title: Yield trends on long-term dryland wheat rotations at Lethbridge.
Publication: Canadian Journal of Plant Science. (1981) 61:609-619.

To Find People to Hand Weed Organic Farms, Send Them to Jail

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Without herbicides to control weeds, organic farms have to find people to pull weeds by hand. Workers are hard to find because hand weeding is drudgery. One solution is to tap into the prison population in the US…

“In a lush field southeast of Iowa, convicts serving time for theft, drug dealing and other crimes are hoeing weeds in what is planned as the state prison system’s first organic farm.”

“In the future, as many as 1,000 acres of prison farms throughout Iowa may be converted to organic crops, said Deputy Iowa Corrections Director Roger Baysden. … ‘This is perfect for prisons,’ Baysden said. ‘What I have got is labor, and I can save money on the chemical side by putting inmates to work with hoes. That is what the public really wants to see anyway.'”

Author: William Petroski
Affiliation: The Des Moines Register staff writer
Headline: Prison farm going organic; Inmates tend crops without chemicals
Publication: The Des Moines Register, Monday, 19 July 2004.

Fungicides are Key to Canada’s Large Chickpea Crop

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Chickpea is among the newest crops in West Canada, where it has been produced in sizeable quantity since 1997. Canada is now a competitive producer, processor and exporter of chickpeas, with exports valued at $50 million per year. Fungal diseases pose the most important constraints on chickpea production in Canada – ascochyta blight is the most problematic. Fungal infections cause initially small whitish spots that enlarge to become tan colored as the cells in the leaves die. Stem infections are considered very damaging as they often cause stem breakage, thereby destroying healthy branches.

“Ascochyta blight of chickpea has been a major biotic constraint to chickpea production in Saskatchewan where the vast majority of Canadian chickpea is grown. Under conditions conducive for disease development, yield losses of close to 100% have been encountered in the Canadian prairies. … Host plant resistance to the pathogen is partial and plants become increasingly more susceptible with the initiation of flowering. Major resistance breakdown due to genetic changes in pathogen populations has been observed in Saskatchewan.”

“The timely and efficient use of fungicides has remained a major factor in the successful management of the disease and the economic viability of the crop.”

Authors: S. Banniza¹, C.L. Armtrong-Cho¹, Y. Gan² and G. Chongo¹.
Affiliation: ¹Crop Development Centre, University of Saskatchewan; ²Agriculture and Agri-Food Canada, Saskatchewan
Title: Evaluation of fungicide efficacy and application frequency for the control of ascochyta blight in chickpea.
Publication: Canadian Journal of Plant Pathology. (2011) 33(2):135-149.

North American Ginseng Production Depends on Fumigation

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Roots of American ginseng are common ingredients in herbal medicines. However, being a root crop subjects ginseng to attacks by soil-dwelling organisms, which cause root rot of ginseng seedlings. In order to prevent damage to the roots, growers typically fumigate fields before the ginseng crop is planted.

“An important component of many traditional Asian herbal medicines is dried root of American ginseng (Panax quinquefolius L.). … Although indigenous to the forests of eastern North America, most of the world supply of dried root is now provided by crops grown in cultivated fields under artificial shade structures. Over two-thirds of Canada’s ginseng crop is grown in the sandy soils of southwestern Ontario.”

“Current production methods provide environments favourable to disease development, and crop loss due to disease is significant. Although ginseng germplasm is diverse, disease-resistant cultivars are not available. … To reduce risk of damage from soilborne species of Pythium and nematodes, ginseng growers normally fumigate fields prior to seeding.” 

Authors: R.D. Reeleder¹, J. Miller¹, B. Capell¹ and J. Schooley²
Affiliation: ¹Agriculture and Agri-Food Canada, Ontario, Canada; ²Ontario Ministry of Agriculture, Ontario, Canada.
Title: Mefenoxan sensitivity and the impact of fumigation on Pythium species and Phytophthora cactorum in ginseng soils.
Publication: Canadian Journal of Plant Pathology. (2007) 29:427-436.

IPM Research in Turkish Tomato Fields Shows Importance of Fungicide Sprays

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Tomatoes are a major vegetable crop grown in Turkey with an annual production of about 10 million tons. Fresh market tomatoes account for 80% of production while canned, dried and paste products from Turkey’s 55 tomato processing plants account for the remaining 20%. Late blight is a devastating disease of tomatoes for which Turkish farmers typically spray twice a season. However, IPM research has shown that 5 carefully-timed applications are much more productive.

“In 1997, Phytophthora infestans (Late Blight) caused an epidemic and great crop losses, especially in the Marmara and Trakya regions. Turkey, as a tomato paste producer, had to import tomato paste to satisfy the contracted commitments. IPM studies were conducted by Ege University, Faculty of Agriculture and Department of Plant Protection in Marmara Region (Bursa) during the years 2000-2005.”

“In all IPM programs, a total of 5 fungicide applications were made depending on which IPM program was followed. … The grower’s standard had two fungicide applications when first symptoms appeared. All of the IPM weather timed spray programs increased marketable tomato yields resulting in higher net economic returns to the farmer. The growers recognized how poorly their standard spray program yielded, resulting in lost income to their farm operation.”

Authors: H. Saygili, N. Tosun and H. Türküsay.
Affiliation: Ege University, Faculty of Agriculture, Izmir-Bornova, Turkey
Title: Integrated Disease Management in Processing Tomato in Turkey
Publication: Acta Horticulturae. 2007. 758.

Climate Change Increases Need for Fungicides in Egypt

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The earlier seasonal onset of warm temperatures in parts of the world is resulting in a threat of earlier disease development. With an increase in the potential for more severe epidemics, the number of fungicide applications needed for control also increases. Researchers have determined that 1-3 more fungicide sprays will be needed in Egypt to control tomato diseases as a result of climate change…

“The ranges of several important tomato disease[s] in Egypt; including tomato late blight (the most destructive tomato disease causing fruit yield losses) have expanded since the early 1990s, possibly in response, in part, to climate trends. … Based on analysis of plant/disease/climate relations, an epidemic of late blight onset on tomatoes that is 1-2 weeks earlier means 2-3 additional sprays to achieve sufficient control of late blight. Accordingly, 1-3 more sprays will be applied at the incoming decades of the 2025-2100.”

Authors: M.A. Fahim¹, M.K. Hassanein¹, A.F. Abou Hadid² and M.S. Kadah²
Affiliation: ¹Central Laboratory for Agricultural Climate, Giza, Egypt; ²Climate Change Information Center, Giza, Egypt
Title: Impacts of climate change on the widespread and epidemics of some tomato diseases during the last decade in Egypt
Publication: Acta Horticulturae. 2011. 914.

Without Fungicides, Fungal Infections Would Render Celery Unmarketable

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Septoria late blight is a worldwide disease of celery plants. First reported in Italy in 1890, late blight was then reported in North America in 1921, leading to losses of 25-50%. The disease is explosive – a half billion spores can be produced on a single celery plant. Each spore can start an infection resembling a dark spot, which can grow large enough to cause leaf death. Celery growers spray fungicides to prevent septoria infections. Another option is to use laborers to trim off the infected parts of the celery; however, this is not practical.

“Septoria late blight is an important disease of celery worldwide. Yield loss ≤ 70% can occur. … Effective management of septoria late blight is essential for the production of a marketable crop of celery. The disease threshold for celery is effectively zero because plants with noticeable lesions on leaves and petioles [stalks] are unmarketable, so diseased petioles must be removed by hand. … Septoria late blight is difficult to control once present in a field, and celery growers must rely on application of foliar fungicides to manage this disease. The labour requirements to trim fresh-market celery with lesions are high, and loads of processing celery showing disease symptoms can be rejected entirely.”

Author: C.L. Trueman, et al.
Affiliation: Department of Plant Agriculture, University of Guelph, Ontario
Title: Evaluation of disease forecasting programs for management of septoria late blight (Septoria apiicola) on celery.
Publication: Canadian Journal of Plant Pathology. 2007. 29:330-339.

Climate Change Warms Up Finland – Increased Need for Fungicides Results

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Finland is the northernmost country in the world with successful agriculture. Long harsh winters and low temperatures limit effective production of most crops. However, the cold climate also limits the proliferation of fungal pests. Now that the climate of Finland is heating up, the need for fungicides has grown.

“On average, since the 1960s there has been a trend of the growing season starting 2.1 days earlier per decade in the east and north of Finland, and 2.8 days earlier per decade in the west, with the pace of development accelerating since the 1980s.”

“With a longer growing season plant pathogens will thrive. For example, studies based on simulation models indicate that an increase of 1°C in mean temperature in southern Finland extends the period when potato late blight control (Phytophthora infestans) is necessary by 10-20 days, which means 1-2 more fungicide applications per season. The need for plant protection measures for potato late blight control has already increased following climate change, and the epidemiology of the pathogen has also changed substantially.”

Authors: K. Hakala, et al.
Affiliation: MTT Agrifood Research Finland, Plant Production Research, Jokioinen, Finland
Title: Pests and diseases in a changing climate: a major challenge for Finnish crop production.
Publication: Agriculture and Food Science. 2011. 20:3-14.

Sustainable Ag Pioneers Learn Value of Modern Herbicides

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Dick and Sharon Thompson of Boone, Iowa are pioneering giants of the sustainable agriculture research agenda in the U.S. They helped found Practical Farmers of Iowa. Since 1986, the Thompsons have conducted on-farm research trials and have produced an annual report. The Thompson farm is not organic; however, they generally do not use herbicides, preferring to use a rotary hoe to destroy weeds. In most years, the mechanical control works well, but then came the very rainy 2008 growing season…

“2008 was not a good year for soybeans because of weather, rain and more rain. This was the first year that we lost money on a soybean field. We could not rotary hoe. The beans were good size when we cultivated the first time (June 24). The cultivator threw soil in and around the bean plants, looked like an excellent job. It rained 1.25 inches two days later on June 26 starting all the weed seed we pushed into the row. We had grass in the row, which is not the norm, along with broadleaf weeds. … The field was a mess. The rope wicks attached [to] our old hyboy filled with round up [herbicide] went up and back on the same rows to kill the weeds so that our small combine could harvest the field. The rope wick killed the weeds and the combine was able to handle the dead weeds. The yield was 37 bushel per acre, 7 bushel below county average of 44 and we lost $49 per acre. The field was sprayed for aphids adding more expense.”

“We could not manage weeds in the end rows of corn and soybean fields without herbicides.”

Authors: Dick and Sharon Thompson
Publication: Thompson Agriculture Alternatives 2009 Report
Available at: http://www.practicalfarmers.org/resources/alternatives-in-agriculture.html