Used coffee grounds are effective at destroying the larvae of mosquitoes carrying dengue, yellow fever, West Nile virus, malaria and other diseases.

Biocontrol Beat reports on the promising research of Hermione Bicudo at Universidade Estadual Paulista in Sao Paulo, Brazil:

“Approximately four full soup spoons of used coffee grounds in a 250 mL glass of water killed 100% of aquatic mosquito larvae. This translated into fewer adult mosquitoes (the biting, blood-sucking stage) and less new mosquito egg laying (thus, lower mosquito populations over time).”

Combined with elimination of mosquito breeding sites, used coffee grounds could be useful in integrated pest management programs to slow pesticide resistance and reduce mosquito breeding.

Three new leaf lettuce breeding lines with resistance to corky root, a serious disease of lettuce, have been released by the Agricultural Research Service of the U.S. Department of Agriculture.

Corky root is caused by a bacterium called Sphingomonas suberifaciens which lives in the soil and attacks the plant’s roots, causing them to enlarge and develop yellow to brown lesions and longitudinal cracks, taking on a cork-like appearance. Once infected, the roots are unable to effectively absorb water and nutrients, resulting in smaller lettuce heads and yield loss.

Cultural practices and fumigation techniques used to treat corky root are costly and labor-intensive. Developing lines with genetic resistance is still the most common and preferred method to combat the disease.

The new leaf lettuce breeding lines — one red leaf lettuce and two green leaf lettuces — have plant weight comparable to or higher than commercial cultivars. The breeding lines have also showed little to no tipburn in test trials. They can be used commercially for production of fresh lettuce or to develop new cultivars.

Source: Agricultural Research Service

Corrugated plastic bins can be reused durable nesting shelters for wild bees, according to an Agricultural Research Service (ARS) research entomologist.

Female wild bees will readily use a properly placed, suitably furnished tote as a shelter for their nests, according to James H. Caneof the ARS Pollinating Insects Biology, Management and Systematics Research Unit in Logan, Utah.

Turned on their long side, the totes can be held firmly in place on a wooden or metal post by means of a lightweight steel chain and a customized metal support frame.

Cane came up with the idea of using corrugated plastic totes (like those used for handling mail and packages) as nesting shelters, and has tested them during spring and summer in California, Oregon, Wyoming and Utah. His experiments show that the lightweight, rectangular bins, each 23-1/2 inches long by 15-1/2 inches wide by 15-1/2 inches high, serve as a sturdy, inexpensive and reusable shelter for protecting bee nests against wind and rain.

Growers, professional and hobbyist beekeepers, and backyard gardeners who want wild bees to live near and work in their fields, orchards, vineyards or home gardens can use the totes to house nesting materials, such as five-sixteenths-inch diameter paper drinking straws enclosed in cardboard tubes and stuffed inside empty cardboard milk cartons. Wild female bees such as the blue orchard bee, Osmia lignaria, can use the straws as homes for a new generation of pollinators.

Wild bees are needed now, perhaps more than ever, to help with jobs usually handled by America’s premier pollinator, the European honey bee, Apis mellifera. Many of the nation’s honey bee colonies have been decimated by the puzzling colony collapse disorder or weakened by varroa and tracheal mites or the microbes that cause diseases such as chalkbrood and foulbrood.

A single corrugated plastic tote can accommodate as many as 3,000 young, enough to pollinate one-half to one-acre of orchard. And, unlike bulky or stationary shelters, the tote houses can easily be moved from one site to the next.

Source: Agricultural Research Service

Recognized globally as an ideal means of conserving soil and water while also storing soil carbon, the agricultural practice known as “no-till” may not be applicable under all environmental conditions.

No-till farming means leaving residue left on the soil surface after harvest in place rather than plowing it under. Compared to plowing, no-till has myriad benefits: less labor, less machinery wear, decreased fossil fuel consumption, reduced soil erosion, improved soil productivity, increased wildlife habitats and a better method of maintaining and conserving soil water.

No-till is considered a successful carbon sequestration practice when carbon input (storage) exceeds carbon output (loss). Carbon input includes crop residues, winter cover crops, complex farming systems, and use of compost and manure. The output includes losses of carbon by decompositon, erosion and leaching.

Ohio State University soil scientists recently measured carbon levels in no-till fields throughout seven states and found that soil texture, moisture, temperature, and terrain parameters affected the amount of carbon stored on the soil surface.

“No-till is not applicable everywhere as a means of practicing carbon sequestration,” says Rattan Lal, soil scientist at Ohio State’s Ohio Agricultural Research and Development Center. “There are situations where other carbon sequestration methods would be more effective. I’m not saying that no-till is not good. It is a good practice, but it does not work for all soils, for all crops and all conditions. We must not make carbon sequestration synonymous with no-till. The strategy is to develop a system of soil management in which carbon input into the system exceeds the output.”

Lal and his colleagues studied no-till fields in Ohio, Michigan, Indiana, Pennsylvania, Kentucky, West Virginia and Maryland and identified situations where the practice was the most effective in storing carbon and where it was not.

“Basically, those soils that are well-drained, are silt/silt-loam in texture, warm quickly and have some sloping characteristics prone to erosion are excellent candidates for no-till. Clay soils or other heavy soils that drain poorly, are prone to compaction and are in areas where the ground stays cooler may not always increase carbon storage through no-till.”

In Ohio, for example, the researchers found that no-till would store carbon on about 40 percent of the state’s cropland. In actuality, no-till is practiced on 35 percent of Ohio’s field crops, said Lal.

“Globally, no-till is practiced on only 6 percent of the total cropland and mostly practiced in the United States, Canada, Brazil, Australia, Argentina and Chile. There’s a reason for that — because it can be worked into practices in which carbon input exceeds carbon output.”

In situations where no-till may not be ideal, there are plenty of other carbon sequestration methods available, including mulching, cover crops, complex crop rotations, mixed farming systems, agroforestry, and biochar (a charcoal-like biomass material).

The study also compared carbon levels between no-till and conventional tillage fields and found that, in some cases, carbon storage was greater in conventional tillage fields. But the key is soil depth.

“If you compare carbon storage between no-till and plowed fields with the plow depth, or the first 8 inches of the soil, carbon storage is generally much greater in no-till fields than in plowed fields. But if you go deeper, say 12 inches and deeper, one may find more carbon stored in plowed fields than in no-till.”

Farmers should not measure soil carbon based just on surface depth. Lal recommends going to as much as 1 meter (3.25 feet) below the soil surface.

Lal said that the study is not a criticism of no-till and its benefits, but simply a way of determining where the practice best fits and where other carbon sequestration methods may work better.

“In situations where no-till is ideal, it’s a sustainable soil management practice that simply can’t be ignored,” said Lal. “It saves time, money and wear on machinery and its profit margin is much higher than plowing.”

Source: Ohio State University College of Food, Agricultural, and Environmental Sciences

Researchers at Virginia Tech, Oak Ridge National Laboratory, and the University of Georgia have produced hydrogen gas pure enough to power fuel cells by mixing 14 enzymes, one coenzyme, and cellulosic materials like woodchips or grass.

The group announced three advances from their “one pot” process: 1) a novel combination of enzymes, 2) an increased hydrogen generation rate — to as fast as natural hydrogen fermentation, and 3) a chemical energy output greater than the chemical energy stored in sugars – the highest hydrogen yield previously reported from cellulosic materials.

“In addition to converting the chemical energy from the sugar, the process also converts the low-temperature thermal energy into high-quality hydrogen energy – like Prometheus stealing fire,” said Percival Zhang, assistant professor of biological systems engineering at Virginia Tech.

The researchers used cellulosic materials isolated from wood chips, but crop waste or switchgrass could also be used. Using cellulose instead of starch expands the renewable resource for producing hydrogen to include biomass.

“If a small fraction – 2 or 3 percent – of yearly biomass production were used for sugar-to-hydrogen fuel cells for transportation, we could reach transportation fuel independence,” Zhang said.

The research results have been published in the Wiley journal ChemSusChem (Chemistry and Sustainability), in an article titled “Spontaneous High-Yield Production of Hydrogen from Cellulosic Materials and Water Catalyzed by Enzyme Cocktails.”

• Growth Spurts
• Designing and Building Fuel Cells

Grass filter strips placed in riparian zones not only curb soil erosion, but also block and degrade the widely used herbicide atrazine, Agricultural Research Service (ARS) scientists report.

Atrazine has been used extensively to suppress weeds in corn production for decades, but because it’s applied directly to soil it’s especially prone to losses in surface runoff. The contamination of surface water by atrazine and its less-toxic breakdown components has raised ecological concerns.

Riparian zones are transitional areas between upland areas, such as crop fields, and water bodies. The grasses and other vegetation in these zones help reduce pollution in streams and lakes.

In studies of the effect of different grass species on herbicide transport and degradation, eastern gammagrass showed the highest capacity for promoting atrazine degradation. Orchardgrass, smooth bromegrass, and switchgrass were also effective.

The studies have shown that grass buffers reduced the transport of herbicides to shallow groundwater and in runoff. These buffers can reduce herbicide transport through trapping of sediment and by increased infiltration of water into the soil.

Source: Agricultural Research Service, USDA

• Plants and Seeds

With U.S. milk prices collapsing after two years of historical highs, an old dairy program reauthorized by the 2008 Farm Bill may aid dairy producers by adding additional income over the coming months.

Dairy producers are being encouraged to sign up for the Milk Income Loss Contract (MILC) — a program that provides monthly payments to producers when market prices drop below the program’s defined trigger price.

MILC was first authorized by the dairy title of the 2002 Farm Bill, and after years of extensions has been included in the 2008 dairy title of the Food, Conservation and Energy Act. MILC now includes a feed cost adjuster and increases in both the payment rate and production eligibility among small to medium-sized dairy farms.

“MILC functions similarly to the old grain countercyclical payment programs,” says Cameron Thraen, an Ohio State University Extension dairy economist. “The program has an identified target or trigger price and when the market price drops below that trigger price, the difference between the two is calculated and farmers receive 45 percent of that difference.”

With milk prices tumbling nearly 35 percent in just the past few weeks due to decreased domestic and global demand and the outlook for 2009 looking grim, Thraen said that dairy producers should act quickly to sign up for the MILC program.

“There is absolutely no cost to sign up for the progrom. Any producer who is not signed up for the program or is not thinking about signing up is missing an excellent opportunity.”

Thraen reminds producers that participating in the previous MILC program does not automatically enroll a producer in the current program. New sign-up forms must be completed and submitted.

Details of how the program works are available in a series of documents located on Thraen’s OSU Extension website. The information includes a spreadsheet that allows dairy producers to calculate monthly eligible milk shipments, MILC payments, and total anticipated revenue from the program based on actual or estimated monthly milk and feed prices throughout fiscal year 2009.

The following are some basics dairy producers should know about MILC:

• Sign-ups for MILC began on Dec. 22, 2008. Producers can sign up anytime during 2009 to be eligible to receive potential payments, but must do so the month prior to when they would like to enter the program. Producers can sign up to participate in MILC by contacting their local Farm Service Agency.
• The cap on milk production to remain eligible is 2.985 million pounds per fiscal year. Once a dairy farm’s monthly milk shipment reaches the cap, the producer is no longer eligible to receive payments for the current fiscal year.
• There is no cost to sign up for the program. But once sign-up occurs and a start month is selected, there can be no adjustments. That is, if a farmer enters the program during a time when there are no triggered payments, that farmer cannot readjust eligibility to a future date.
• New to MILC for the 2008 Farm Bill is the inclusion of dairy feed costs, which are calculated into the projected payment. The adjustment was made to reflect market shifts based on corn, soybeans and alfalfa prices.
• Payment per hundredweight is based on 45 percent of the difference between the market price and feed price adjusted MILC trigger price.

Source: Ohio State University College of Food, Agricultural, and Environmental Sciences

• Growth Spurts
• Husbandry
• Market Watch

Farmers know that agricultural equipment can cause compaction in no-till crop fields, but Ohio State University researchers have found that, depending on soil type, compaction can be severe and persist for years.

Based on 20 years of compaction studies at various locations in Ohio, just one year of harvest traffic on clay soils can reduce corn yields by as much as 40 percent, and the impacts from compaction can persist for as long as eight years. The research, “Axle-Load Impacts on Hydraulic Properties and Corn Yield in No-Till Clay and Silt Loam,” has been published in Agronomy Journal.

“This is one of the few long-term compaction studies in the nation. We know that equipment causes compaction, but we wanted to know how long that compaction lasts and how severe it really is,” said Rattan Lal, an Ohio State University soil scientist with the Ohio Agricultural Research and Development Center. “What we’ve learned is that it’s better to take steps to prevent compaction rather than run into the difficulties associated with compaction and struggle to try to eliminate it.”

Lal and his colleagues made a one-time distribution with a single axle 20-ton grain cart and a single axle 10-ton grain cart across fields with two types of soils: clay and silt loam, and then measured how long it took for the fields to recover from the effects of compaction. While compaction from clay soils persisted for years, silt loam soils escaped serious compaction problems.

“Unlike silt loam soils, clay soils drain poorly and don’t respond to the freezing and thawing process during winter, so compaction tends to persist more and its impact on crop growth and yield is much more severe,” said Lal.

Farmers can reduce the compaction hazard through a variety of methods:

• Practicing minimal tillage techniques, such as chisel plowing or subsoiling.

• Relying on soil critters, such as earthworms, to break up the soil through natural processes. The study found that compaction can have an impact on earthworm populations, decreasing numbers 70 percent in clay soils and 50 percent in silt loam soils.

• Growing a cover crop, such as alfalfa, that has a taproot system and can extend deep into the soil. Research Lal conducted in Africa using pigeon peas, a type of taproot plant, showed compaction was eliminated within two years.

• Leaving crop residue in the field. The residue acts as a buffer to dissipate any wheeled traffic.

• Using dual-axle instead of single-axle equipment and wider tires to distribute weight.

• Practicing controlled traffic — a method whereby all farm equipment is the same width so that traffic is confined to specific paths year after year, and the remainder of the soil is untouched.

• Planting or harvesting crops only under ideal environmental conditions. Lal’s compaction research also found that working in fields during rainy conditions increased the severity of compaction.

Lal plans to continue the long-term compaction study, compacting the soil every year and then implementing various control techniques to determine which one would work best.

Compaction can have a number of impacts on the soil and the plants growing in it. Compaction destroys the soil structure and causes erosion by keeping water out. It prevents plant roots from penetrating deep into the soil, and traps carbon dioxide while preventing oxygen from reaching plant roots. The result suffocates the plant either killing the plant or impacting yield performance.

Source: Ohio State University College of Food, Agricultural, and Environmental Sciences

• Growth Spurts

Two new sugarcane cultivars specifically developed for Florida’s sand soils have been released by the USDA Agricultural Research Service.

The new cultivars, CP 00-1446 and CP 00-2180, were developed at the ARS Sugarcane Field Station in Canal Point, Florida, as part of an effort to provide growers with more cultivars that yield well on sand soils. The new cultivars are the result of cooperative research with the University of Florida and the Florida Sugar Cane League, Inc.

During testing, potential sugarcane cultivars are evaluated on their yields of cane and sugar. Both CP 00-1446 and CP 00-2180 produced high quantities of cane, and their sugar yields were 32 percent and 15 percent higher, respectively, than the sugar yield of a commercial variety used for comparison.

Growers in Florida usually get three annual harvests from one planting of sugarcane. Both new varieties produce very high cane yields for the first harvest and moderate yields for the other two harvests, commonly referred to as ratoons.

Florida produces more sugar than any state in the United States. The majority of the sugarcane is produced in organic soils along the southern and southeastern shore of Lake Okeechobee in southern Florida. Twenty percent of Florida’s sugarcane acreage is grown on sand soil.

Seed cane of the releases is available from the Florida Sugar Cane League, Inc., for commercial planting. Small quantities of seed cane for research purposes can be obtained from the ARS Sugarcane Field Station.

Source: Agricultural Research Service

In the six years since New York growers began adopting high tunnels — 20-by-100-foot unheated movable plastic structures that can cover 300 plants — tomatoes have been the most commercially successful.

In high tunnels, heat-loving tomato plants that can be trellised vertically and will bear continuously. A 25-pound box of U.S. #1 top-grade tomatoes sells for $40 to $50 wholesale, while field-grown tomatoes (with their unavoidable cracks and slight blemishes) may bring a grower only $5.

Chris Wien, Cornell University professor of horticulture and the leader of high tunnel research projects funded through the New York Farm Viability Institute, says he expects the use of high tunnels in New York to return a gain of $500,000 per year in the farm-gate value of the state’s horticultural crops by 2010.

Cornell extension specialists are assisting farmers across the state who want to adopt the technology. A half-dozen high tunnel vegetable research projects are currently under way on farms in several counties. These projects are funded by the New York Farm Viability Institute.

“We want to be sure that there’s a sustainable system in place by which high tunnel technology is easy to come by, and there’s a knowledgeable extension staff available to help,” says Wien, who has worked with growers producing diverse crops, including tomatoes, watermelon, cantaloupe, cabbage and onions, using high tunnels up to 300 feet long.

Source: Cornell University

• Tomatoes
• Greenhouses
• The Hoophouse Handbook: Growing Produce and Flowers in Hoophouses and High Tunnels