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When a plant wilts, it is an indication of a serious problem. It may be a problem that can be solved quickly. However, a wilting plant is one that is not functioning properly. The leaves and stem are able to maintain the form and structure that we find so familiar due to a constant supply of water. Water is supplied from the soil, transported up the stem and finally, evaporates through tiny pores in the leaves. This process must be maintained if the plant is to be productive.

Wilted plants have had an interruption in the above process. This article briefly describes some of the problems that might lead to a wilted plant. Even if the plant cannot be saved with quick action, proper diagnoses may allow one to avoid the problem in the future.

Perhaps first we should have a definition of wilt. A wilted leaf will be limp and flaccid. This is in contrast with a leaf that is bent down, but is stiff and retains its shape. Eventually, a wilted leaf may die and become stiff. Plants that exhibit wilt are shown in images one and two.

The most obvious problem that may cause a plant to wilt is drought. Yet, this simple possibility should not be overlooked. If plants are wilting, look for moisture in the soil. Dig down into the root zone; don’t be content to observe the surface appearance of the soil. Does the pattern of wilting plants in the field follow the drier portions of the field? Are adjacent weeds wilting? Young plants may not have developed sufficient root systems to avoid wilting in dry weather. In sandy soils the lateral movement of water is restricted and may not reach young transplants. Growers may choose to use a tensiometer so that the moisture in the soil can be measured and irrigations can be planned accordingly.

Water can also be a problem if there is too much of it. The roots of most plants will not function properly unless there is air exchange between the root and the air spaces that surround the root. Waterlogged roots may cease to function, thus causing the plant to lose the ability to take up water. Often the symptoms associated with roots that have been waterlogged do not show up until after the water has receded.

If the plants in question appear to be getting an appropriate amount of water, it may be necessary to check the appearance of the roots. Carefully dig up wilted plants. Healthy roots should look white or light tan (you may have to check a healthy plant for comparison). The roots should feel firm to the touch. Along with large structural roots, smaller “feeder” roots should be present. Dark, discolored rotten roots may be a symptom of fungal infection. It is not uncommon to find rotten roots in soils that have been too cool and too wet. Examples of root rots caused by fungi include Pythium, Phytophthora and Rhizoctonia root rots.

The roots may be fine, but if the stem is not healthy, water cannot get to the rest of the plant. Cut open the stem of the plant near the base. Depending on the plant, the inside of the stem should be a creamy white or green. Brown or dark discoloration indicates a problem ( Image 1). Fusarium spp. and Verticillium spp. are examples of fungi that cause vascular wilt. That is, these fungi plug the plant’s plumbing in the stem. This is why the stem looks discolored. Other vascular wilts may cause discoloration or cause other symptoms that the growers should become aware of.

Plants may wilt due to damage to the lower stem. Some diseases, such as Phytophthora blight, may cause damage to the stem and cause a wilt ( Image 2). Physical damage to the stem, such as from wind, may cause a plant to wilt. Fertilizers may injure the stem or roots if applied improperly. Such injury may look like physical damage.

Finally, some insects will bore into the stem and damage the vascular tissue. An example would be squash vine borer of squash and pumpkin. A hole resulting from the insect entry or exit should be visible as well as frass (insect poop). An insect in adult or larvae form may be observed in the stem.

While the wilt one observes this year may be irreversible, it will be valuable to understand the problem so that corrections may be made next year.

Organic matter amendments and the development of disease suppressive soils

In a study currently underway at the University of Illinois we are evaluating the effects of several different cropping systems and organic matter amendment applications during the three-year transition from a conventional to an organic crop production system. One of the components of this study is to monitor the effect of these treatments on the disease suppressive properties of the soil during and after the three-year transition period.

A disease suppressive soil is one in which the level of disease that develops on plants grown in that soil is less than that which develops on plants grown in other soils under similar conditions. However, almost all soils have some disease suppressive properties, so the phenomenon of disease suppressive soil should be thought of on a continuum of low to high levels of suppression, rather than thinking of soils as being either disease suppressive or conducive. In many cases the disease suppressive nature of a soil is the result of the presence and activity of the microorganisms in the soil. Bacteria, fungi, and soilborne fauna can all act to change the suppressiveness of a soil. If a soil is sterilized and then infested with a plant pathogen, the amount of disease that occurs on plants grown in that soil will usually be much greater than the amount of disease that occurs on plants grown in the same but non-sterilized, pathogen infested soil.

One strategy that has received a lot of attention for its potential to elevate the disease suppressiveness of a soil is addition of organic matter. A number of studies have shown that disease levels are reduced following the incorporation of organic matter into the soil. However, a survey of the plant pathology literature quickly shows that this is a complex phenomenon, and that simply adding organic matter to a soil will not necessarily lower the amount of diseases that develop on plants grown in these amended soils. Not all organic matter amendments produce the same results, and an amendment that works well in one situation may not work at all in another. Where, when, and how well the addition of organic matter increases disease suppressiveness depends, in part, on the mechanism involved in changing the level of suppression. Several mechanisms have been identified as contributing to disease suppression following the addition of organic matter. These include the stimulation of non-pathogenic microorganism that inhibit or kill the pathogens through competition or parasitism, the release of compounds that are toxic to the pathogens, or the stimulation of the host plant’s disease defense system.

Some organic amendments are thought to work primarily by altering the structure of the microbial communities in the soil or by changing the physical and chemical properties of the soil. A study on the effects of organic amendments on potato early dying disease found that higher levels of soil organic matter following additions of organic residues were associated with lower disease levels, with the speculation that the disease reductions were due to increased nutrient holding capacity of the soil, increased water infiltration and decreased soil crusting.

Another study on the effects of organic amendments on sugar cane root rot found that disease levels were reduced when non-sterilized composts were added to the soil, but that disease suppression did not occur when the composts were sterilized prior to incorporation. This suggests that the microorganisms present in the non-sterilized composts were responsible for the suppression of disease. Several studies have shown a reduction in disease associated with increases in general levels of soilborne fungi and bacteria following the addition of organic matter, such as the addition of chicken litter or the incorporation of certain cover crops. In some cases the disease reductions were tied to increases in specific organisms such as the bacterium Pseudomonas putida, or several species of the biological control fungus Trichoderma.

Certain types of organic matter have been investigated for their ability to release toxic compounds that inhibit or kill soilborne plant pathogens. The incorporation of Sudan grass cover crops has been shown to reduce nematode and fungal diseases of lettuce and potatoes. The fact that Sudan grass was able to lower disease levels while equivalent amounts of other types of organic matter were not, and that incorporating two-month-old Sudan grass provided better control than three-month-old Sudan grass, lends support to the hypothesis that compounds called cyanoglucosides, released by the decomposing grass tissues, are toxic to the pathogens in the soil. Recently, use of broccoli residues have been shown to be effective for controlling diseases caused by the soilborne fungi Fusarium oxysporum, Rhizoctonia solani and Verticillium dahliae, and reducing the soil populations of these pathogens. In this case, it is believed that compounds call glucosinolates, released by the decomposing broccoli tissues, are responsible for reductions in pathogen populations. In some studies the incorporation of broccoli residues was enough to lower disease levels, while in others control was only achieved when the soil was tarped with plastic sheeting immediately after the broccoli was incorporated. Other pathogen inhibitory chemicals released during the decomposition of organic matter are thought to include ammonia, nitrous acids, alcohols and aldehydes.

Although we usually think of disease suppressive soils as having the ability to suppress soilborne, root infecting plant diseases, there is also evidence that shows that organic amendments can have an effect on the levels of foliar diseases as well. Soil incorporated paper mill residues were shown to lower foliar disease levels of cucumbers and snap beans, and cannery waste added to tomato plots resulted in lower levels of bacterial spot on tomato fruit. Since the soil treatments are not directly in contact with the pathogens, these cases where foliar diseases are affected by soil treatments may be the result of a change in the plant’s nutrient status or a stimulation of the plant’s disease defense system, a phenomenon called systemic acquired resistance.

Addition of organic matter does not always result in reduced disease levels, and in some cases organic matter amendments have been shown to actually increase disease levels. A velvet bean cover crop mulch was found to increase losses in a collard crop due to elevated levels of wirestem, caused by Rhizoctonia solani, and while high levels of organic amendments were found to lower levels of anthracnose on beans, lower levels of the same amendment were found to increase the amount of anthracnose in a greenhouse study.

While the studies on the effects of organic matter amendments show promising results for increasing the disease suppressiveness of soils, there are also studies that show little or no disease control following the application of organic matter. The types of organic matter applied, the physical, chemical and biological condition of the soil being treated, and the crops and pathogens present all have an influence on the process. Researchers note that the large amounts of organic material needed, the amount of time lost to rotational cropping, and the variable levels of effectiveness may make this disease control strategy impractical in some situations, and they warn that such a strategy should always be used as part of an integrated pest management approach, along with other control methods, such as the use of resistant varieties, proper water management, and adequate crop rotation. However, the more we learn about the impact of various organic amendments on the disease suppressiveness of soil, and the mechanisms involved in that suppression, the better able we will be to use this strategy effectively.

Economics of organic field crops

How do the economics of organic field crop production compare to conventional crop production? We are going to attempt to shed light on this very important question by summarizing three university crop budgets and comparing their findings to Gary Reding’s, an organic grower in Indiana, crop budgets. We will also comment on the different risks in organic compared with conventional agriculture.

In terms of comparing returns of organic and conventional production, it makes sense to examine each component separately, where:

One of the reasons to look at each component separately is that there are a lot of assumptions about organic yields, which may or may not accurately reflect the yields in your area.

Reding’s per acre crop budgets
Reding’s crop budgets include corn, soybeans, wheat, hay and popcorn. In projecting revenues using estimates yields and prices, Reding assumed fairly conservative yields. The price of hay in the budgets is the same as conventional as it is only recently that Reding has found a premium market for organic hay and has been able to receive 1.5 times to 2.0 times the value of conventional hay. The buyer is willing to pay $118 per ton delivered to his farm for late-cut first cutting hay.

The cost of fertilizer varies greatly between the organic crop budgets. In Gary Reding’s budget, he has priced the cost of 3 tons of chicken manure and plants either wheat or oats as a cover crop for all crops except hay. Reding’s fertilizer costs are consistent with Farm A in the 2003 Kansas budget. However, the other university budgets, that do not derive their costs from actual organic farms, estimate much higher costs for fertilizer.

A second component of the fertility costs for organic farms is the cover crop. Reding plants either wheat or oats as a cover crop, and so the cost of the cover crop is assumed to be the cost of the wheat seed. Organic farmers often times use saved seed from their own organic production for soybeans and small grains. The seed cost will be less than or equal to conventional seed costs because there are no genetically modified traits to pay for. However, organic producers have reported that seed availability can be an issue. The only crop that is dried in the bin is No. 2 yellow corn. The machinery fuel and repair costs are estimated using the University of Minnesota’s Farm Machinery Cost Estimates for Late 2005, by William Lazarus and Roger Selley. The hauling charges are assumed to be double conventional crop, because the distance to a buyer is likely to be longer. However, many buyers of organic grains pay for the hauling charges, so this may or may be a cost. Reding has assumed a much higher insurance charge than that faced by conventional crops because of the difficulty of finding organic crop insurance.

Summary of per acre variable costs, not including land, labor and machinery
Examining other organic crop budgets, we were not able to find budgets for popcorn or hay, so we only compare the budgets for corn, soybeans and wheat.

Overall, the total per acre variable costs for corn and soybeans appear to be similar for organic and conventional crops. Reding’s total per acre variable costs are higher than most of the organic crop budgets and that is partly due to his decision to be conservative in his estimate of costs. Since Reding is located in Indiana, it is worth noting that his costs for organic production of corn is $4 per acre less and for organic production of soybeans is $14 per acre more than conventional production in Indiana. Since the overall costs of organic and conventional are in the same ball park for corn and soybeans, this implies that the relative profitability of organic and conventional production depends more on the revenue differential than the cost differential.

Wheat, where we could find other organic crop budgets, appears to be more expensive to grow organically than conventionally. (Part of the higher cost on the wheat is the alternating years of fertilizer application. This should technically be spread over all crop years instead of just the applied years.) Reding’s costs for organic wheat in Indiana are $45/acre more expensive than conventional wheat in Indiana. Reding’s costs are also substantially higher than costs in either Kansas, and for spring wheat in North Dakota. It is worth noting that both Kansas and North Dakota have advantage growing wheat relative to the Eastern Corn Belt.

Comparison of organic and conventional revenues
In comparing organic and conventional revenues the area where there are the most assumptions and uncertainty is with respect to organic yields. For example, the South Dakota crop budget assumes that organic yields are 75% of conventional yields. By comparison, an Iowa state research project “Comparison of Organic and Conventional Crops at the Neely-Kinyon Long-term Agroecological Research (LTAR) Site” reported organic soybean yields at or above conventional yields for 2003 to 2005, and organic corn yields at or above conventional yields in 2004 and 2005, though slightly below in 2003. Ohio State also released organic corn yield trials for 2005 with yields ranging from 121.2 to 173.9 with an average of 153 bu/acre at the Bowling Green location and yields ranging from 130.4 to 212.2 with an average of 171.4 bu/acre at the Apple Creek location. For producers who are transitioning to organic production, it is safest to assume that yields will be on the low side, at least for the first few years of production.

With respect to organic prices, the highest prices will be for food-grade corn and soybeans. However, buyers expect very high quality for food-grade organic grains that may be difficult to achieve. Feed-grade corn and soybeans receive a lower price, with the advantage that buyers accept lower quality and many of the feed-grade varieties are higher yielding than the food-grade varieties. Another positive note is that the demand for organic feed is being driven by the rapidly growing organic dairy and livestock sectors. This is causing organic feed grain prices equal to or higher than organic food grain prices in 2006. Over the long term, organic growers should expect to see the prices for organic grains decline as the supply of organic grains increases. In the short term, organic growers can expect organic prices to remain high relative to conventional prices for two reasons: 1) demand for organic grains is growing faster than supply; 2) the 3-year transition period slows the process of conversion of land to organic. The largest threat to high organic prices in the near term is from imports.

Combining information prices and yields for corn and soybeans, Table 3 compares the revenues from organic and conventional crops. Because of the higher prices for organic corn and soybeans, even assuming a 20 bushel yield drag for organic corn and a 14 bushel yield drag from organic soybeans, the revenues from the organic crop are clearly higher than the conventional crops. The worst case revenue scenario on organic corn is still $30/acre higher than the best case on conventional, and the worst case on organic soybeans is $75/acre higher than the best case on conventional.

Economics of rotation
Because the National Organic Program (NOP) requires a minimum of a 3-year rotation for organic crop production, it is important to compare returns over the whole rotation, i.e. for 3 or more years (the North Dakota crop budget provides a good example of this calculation). Here, we examine the estimated earnings for a 1,200 acre farm comparing Reding’s two organic rotations to a similar Purdue crop rotation. Reding’s cc,b,w,h rotation is no. 2 yellow corn, followed by soybeans, wheat and hay with each crop on 300 acres. Reding’s pc,b,w,h rotation starts with popcorn, followed by soybeans, wheat and hay, again with each crop on 300 acres. Purdue’s c-b,c-w rotation is 400 acres of corn in rotation with 400 acres of soybeans and 200 acres of corn in rotation with 200 acres of wheat for 600 acres of corn, 400 of soybeans and 200 of wheat. We assume that all this land faces the same rental charge of $134 per acre, the family and hired labor is paid the same amount. Drying and handling costs are slightly higher for the organic crops.

Comparison of risks in organic and conventional
Conventional wisdom says that organic farming is more risky than conventional, but there has not yet been any research on this topic. Organic farms tend to be more diversified than conventional farms, in part because the NOP requires a minimum of a three-year rotation, and crop diversification is one of the best ways to manage risk. Organic farms face more marketing risks than commodity producers, though the risks are similar to conventional specialty crop producers. The prices of organic crops are totally independent of conventional grains or the futures markets so hedging is out of the question. One advantage is that organic producers can lock in prices before production to minimize risk of price movements. Normally, producers can lock in a profit based on average yields and their remaining risk will be growing conditions. Reding always puts in an act of God clause so that he is only responsible for what the yield is on any particular year from his acreage and does not have to replace any shortfall in production.

As previously discussed, any producer targeting the food-grade organic market will face the risk of not meeting the quality standards. As the organic feed market grows, the penalty for not meeting the food-grade quality standards will decrease. Because the organic market is smaller, producers will likely spend more time negotiating with buyers and may wait longer for payment. Organic corn producers face the risk of GMO contamination from pollen drift. Organic producers also need to maintain good records to manage the risk of losing their certification. Finally, probably the largest risk faced by new organic producers is the “learning curve.”

Transitioning to organic
For an established organic farming operation such as Reding’s, organic farming is clearly profitable compared to conventional farming. That said, the transition to organic farming is still a challenge. In order to be certified organic, the land must be managed organically for three years and during those years the producer will most likely have lower yields and will need to sell at conventional prices. Reding has not found any markets that offer price premiums for chemical and fertilizer-free grain.

If preplanned properly, transition can be planned with the use of fall and early spring planted small grains to minimize the number of seasons it takes to make the transition. By making your last fertilization with conventional products no later in a year than the first date you intend to harvest your first organic crop, you can meet the 36 month prior to first harvest rule. This allows for essentially a two crop season transition time. By planting a forage crop with the small grain crop, you can harvest the small grain the first year and the hay the second year as revenue crops during transition. The forage crop will then provide the green manure to be plowed in for a nitrogen source on your first organic crop to be harvested. This also provides a cover crop during transition and builds your organic matter in the soil. This type of transition plan minimizes the loss of revenue typical of the transition years.

References
Indiana, conventional crop budgets:
http://www.agecon.purdue.edu/extension/pubs/id166_Feb06.pdf
Illinois, corn: http://web.aces.uiuc.edu/value/factsheets/corn/fact-organic-corn.htm
Illinois, soybeans: http://web.aces.uiuc.edu/value/factsheets/soy/fact-organic.htm
North Dakota, multiple crops: http://www.ext.nodak.edu/extpubs/agecon/ecguides/2003org.pdf
Kansas, multiple crops: http://www.kansasruralcenter.org/publications/Organic%20cropping.pdf
Organic field trials in Iowa: http://extension.agron.iastate.edu/organicag/rr.html
Organic field trials in Ohio: http://agcrops.osu.edu/corn/documents/2005OrganicTestReport_000.pdf

United States and regional supply of certified organic field crops and livestock

Popular press has devoted a large portion of reports to the rapid growth in demand for organic products, with overall demand increasing at 20 percent a year. Furthermore, specific sectors of the organic market are seeing even larger demand increases; demand for organic meat grew at 77 percent in 2003 (OTA, 2004). For organic producers and consumers, the other important part of the picture concerns what is happening with the supply of certified organic products. For organic field crop and livestock producers, as the supply of certified organic products increases, these markets will become more competitive both in terms of price and quality. Also, certified organic livestock producers are particularly concerned about the supply of certified organic feed.

This article summarizes the currently available information on United States and regional supply of certified organic field crops and livestock. The USDA, Economic Research Service has published survey data on certified organic operations through 2003 (ERS, 2005).

While the overall trend in supply of certified organic field crops and livestock is increasing, some certified crops and livestock experienced a substantial decline between 2001 and 2002 due to the introduction of the National Organic Program (NOP). The NOP final rule became effective on February 21, 2001 and was fully operational on October 21, 2002. Some farmers decided not to certify their field crop acreage and livestock under the NOP in its first year. For most of these field crops and livestock, the upward trend resumed between 2002 and 2003.

U.S. trends in certified organic field crops
Overall, U.S. certified organic acreage in field crops and hay has increased steadily between 1997 and 2003 figure 1 below. In particular, organic wheat acreage increased steadily and as of 2003 accounted for more certified organic acreage than any other field crop or hay. Acreage in alfalfa hay and other hay also increased substantially, driven by the demand for organic dairy products and meat products. As of 2003, alfalfa hay and other hay ranked second and third in terms of acreage after wheat. Soybean acreage declined in 2002 and 2003 but is expected to increase due to demand for livestock feed. Organic corn acreage increased through 2003 and is also expected to increase due to demand livestock feed.

The other grains category increased substantially between 2002 and 2003 and this category includes milo, triticale, kamut, amaranth, millet, buckwheat, rye and quinoa. Some of these grains such as amaranth, kamut and quinoa are now being marketed as “ancient” grains with a low glycemic index in an effort to capitalize on the “low carb” diet trend. We expect acreage in the other grains category to continue to increase due to the whole grains emphasis in the 2005 Dietary Guidelines for Americans and associated marketing efforts by producers of whole grain food products. Certified organic acreage in oats, barely, spelt, and sorghum remained fairly steady between 1997 and 2003.

Regional trends in certified organic field crops
The Midwest region dominated U.S. production of certified organic corn and soybeans in 2003 which is consistent with the distribution of conventional production as well. Midwestern states produced 82 percent of the United States’ supply of organic soybeans and the top 5 states were Minnesota, Iowa, Michigan, Ohio and Wisconsin. The region produced 77 percent of the United States’ supply of organic corn and the top 3 states were Minnesota, Wisconsin and Iowa. The next section describes the certified organic livestock trends and concludes that the growth in demand for organic dairy and meat will greatly increase the demand for organic corn and soybeans. Clearly, this region which dominated the production of organic corn and soybeans in 2003 will have an advantage in supplying the growing demand for livestock feed.

The Midwest also produced 79 percent of the United States’ supply of organic oats in 2003 and the top 3 states were North Dakota, Wisconsin and Iowa. The region produced 48 percent of the other organic grains and this production was dominated by North Dakota.

The region was not as dominant in the production of hay, although Wisconsin had substantial organic hay production since it was the top organic dairy state in 2003. The region produced 50 percent of the United States’ supply of organic alfalfa hay and the top 3 states were Wisconsin, North Dakota and South Dakota. This region only produced 37 percent of the United States’ supply of other hay and the top 4 states were North Dakota, Ohio, Wisconsin and Iowa. Finally, the region only had 10% of the United States’ supply of organic pasture in 2003, dominated by Wisconsin and North Dakota. As the number of organic dairy operations increase in this region, the supply of organic pasture and hay will also need to increase.

U.S. trends in certified organic livestock and poultry
Overall, U.S. certified organic livestock and poultry have increased steadily between 1997 and 2003 figures 2 and 3 below. In terms of livestock, the major growth has been in the number of certified organic milk cows, driven by the demand for organic milk. The number of certified organic beef cows has also increased. Notably, there was no reduction in the number of certified organic livestock with the implementation of the NOP. While certified organic milk cows and beef cows tend to be raised on pasture and grass-fed, they are also fed organic feed. The large increase in the numbers of organic milk and beef cows will increase the demand for organic corn and soybeans and other feed grains.

For certified organic poultry, the major growth has been in broilers with a small increase in the number of layer hens. The poultry sector experienced a sizeable decline in 2002, followed by a major increase in 2003. Since chickens are primarily fed a ration of corn and soybean meal, the growth in the organic chicken and egg demand will translate into increased demand for organic corn and soybeans.

Regional trends in certified organic livestock and poultry
Within the Midwest region, Wisconsin, Minnesota and Iowa were the dominate states producing organic livestock and poultry in 2003. The region had 45 percent of the United States’ supply of organic milk cows and this was dominated by Wisconsin which had almost one-third of the organic milk cows in the United States. Minnesota also had a substantial number of organic milk cows. The region had 40 percent of the United States’ supply of organic hogs and pigs and this was dominated by Iowa which had almost a one-third of the United States’ supply. In the poultry sector, the Midwest is dominated by layer hens. In 2003, the region had 39 percent of the organic layer hens in the United States, and Wisconsin and Iowa were the top two states. The Midwestern states only produced 3 percent of the organic boilers and 10 percent of the organic turkeys in 2003, again dominated by Wisconsin and Iowa.

Conclusions
There is substantial room for growth in organic field crop acreage and organic livestock in the Corn Belt. In 2003, while less than half of the United States’ supply of organic livestock was in this region, roughly 80 percent of the US supply of organic corn and soybean acreage were in this region. The Corn Belt has a clear advantage in producing organic livestock and poultry relative to the rest of the US because of its substantial feed base. However, the Corn Belt has less of an advantage in producing hay. Going forward, the biggest challenge in the region will be to match the growth in production of organic feed to the growth in production of organic livestock.

Asian soybean rust update for organic producers

We have been fortunate in the upper Midwest to have missed Asian soybean rust in 2005 when the disease was confirmed from Florida to Missouri. The latest confirmed report in 2006 came on June 28, when Dr. Edward Sikora, a plant pathologist of the Alabama Cooperative Extension Service, found rust in a soybean sentinel plot (a plot planted strictly for monitoring the disease) southeast of Mobile Bay. So far in 2006, soybean rust has been found in kudzu as far north as Montgomery County in south central Alabama and as far west as Hidalgo County in southern Texas and on a soybean sentinel plot in Martin County, Florida. Martin County is just north of Palm Beach County on the southeast Atlantic coast. Despite approximately 23 confirmed finds of soybean rust in the south, it is thought that Midwest production of soybeans will not likely be economically affected this year. However, it is interesting to note that in 2006 more rust was observed earlier in the year than in 2005. An animated map showing the dates and the area of the observations for 2005 and 2006 can be found at the following website: http://www.ceal.psu.edu/sbr0506.htm.

Efforts to find effective control strategies for soybean rust in organic soybeans are continuing on several fronts. The collaborative effort supported by USDA-CSREES between Iowa State University, Michigan State University, the University of Florida and the Rodale Institute includes testing approved materials that may have some efficacy. Additionally, USDA-ARS researchers continue to breed varieties with potential resistance to soybean rust. Of particular interest is the work of USDA plant pathologist Marcial Pastor-Corrales who noted that “beans are notoriously susceptible to pathogens,” and “soybean cultivars in Brazil and the United States were very susceptible to the Asian soybean rust pathogen.” During a 2001 trip to South Africa, Pastor-Corrales observed that while the soybean crop was heavily infected, common beans growing a mile away were not. From this observation, he concluded that resistance may be found in common bean cultivars. Relying on this information and with the aid of fellow USDA researchers, Pastor-Corrales identified five dry bean cultivars resistant to Asian soybean rust and is now attempting to characterize the genes responsible for the resistance in order to determine whether they can be useful in breeding a resistant soybean line.

In all cases, whether the growing system is conventional or organic, researchers note that reliance on fungicides may provide only short-term solutions. Effective strategies to manage outbreaks of soybean rust year to year will likely include the use of disease-resistant soybeans, fungicides, optimizing soybean planting dates, adjusting row spacing and planting a range of maturity groups to spread the risk of infection periods.

Our research through the CSREES project has identified that few organic fungicides are available in the current marketplace for Asian soybean rust control. In Iowa, no significant difference in yield was found in non-infected soybeans treated with Ballad™, an OMRI-listed fungicide that has shown some efficacy against soybean rust in South Africa. Results from the University of Florida include work done by Drs. David Wright and Jim Marois where they compared the incidence and severity of soybean rust after fungicide applications. In the first trial, Wright and Marois found that the Oxywater™ reduced the incidence of soybean rust by 45 percent, but the level of rust at the end of the trial was 32.5 percent versus 77.5 percent in the control. In the second trial, Ballad™ at 1 quart/acre reduced soybean rust incidence by 65 percent, but again, the final level at the end of the experiment was a 32.5 percent soybean rust incidence rating in the Ballad™ plots compared to the control at 97.5 percent. The severity of soybean rust was reduced from 6.85 in the control plots (on a scale of 1 to 8 where 1 is the lowest level of severity and 8 is the highest level of severity) to 4.90 in the Ballad™ plots. Increasing the Ballad application rate to 2 quarts/acre did not lead to an increased amount of protection. Thus, early results from Ballad™ applications against soybean rust show some promise; however, to date there remains no fungicides that can be used by certified organic soybean producers that provide the level of control available to conventional producers. We are continuing to test materials across the country in 2006 and will provide periodic updates throughout the season.

Field day planned in Michigan: Enhancing pollination and biological control with native plants

Natural enemies and bees need pollen and nectar to survive, yet many farms provide these resources only during bloom. Michigan State University is studying native Michigan flowering plants that can provide these resources for farmers throughout the growing season. We are hosting a field day on August 1 beginning at the MSU campus farms to provide an update of this project. Planting these native Michigan perennials adjacent to crops could help increase the abundance of these insects over the long term, leading to less need for pesticide sprays and greater fruit set and yield. This field day will help growers see the plants and learn more about which ones are most attractive to bees and natural enemies.

Field day participants will:

• Learn which plants have been identified through MSU research as the most effective at attracting beneficial insects. See additional native plants to be tested.
• Learn which natural enemies common at native plants can help control your crop or garden pests.
• Hear about seeding a prairie strip with hand broadcast and seed drill methods.
• Visit a native plant nursery to learn about plant selection, seeding establishment, and maintenance.

To register, send $20 (for lunch, educational materials) check made payable to Michigan State University; your name, address, phone, and email to: Heather Lenartson, MSU Dept of Entomology, 243 Natural Sciences Bldg., East Lansing, MI 48824.

For more information , email Anna Fiedler at fiedlera@msu.edu or view details at http://ipm.msu.edu/plants/pdf/field-day06.pdf .

Can’t attend the field day? Learn more about native plants and beneficial insects at http://ipm.msu.edu/plants/home.htm

Reports from our organic growers