ARS's new automated spraying system can detect the presence, size, shape and foliage density of trees and then apply the optimum amount of pesticide in real time. Click the image for more information about it.
By Sharon Durham
February 11, 2016
An experimental variable-rate spraying system that helps growers efficiently apply chemicals to trees was developed by Agricultural Research Service (ARS) scientists at the agency's Application Technology Research Unit in Wooster, Ohio. The new sprayer reduced average pesticide use between 46 and 68 percent, with an average cost savings of $230 per acre for ornamental nurseries. The cost savings can be much higher for orchards and other fruit crop productions.
ARS agricultural engineer Heping Zhu, along with engineer Richard Derksen and research leader Charles Krause, developed the laser-guided sprayer that synchronizes spray outputs to tree structures. Their colleagues at the Ohio State University, Oregon State University and the University of Tennessee evaluated the sprayer, which would help nursery, orchard and grape growers apply chemicals to trees. Zhu and his colleagues received a National Institute of Food and Agriculture (NIFA) grant to develop this technology to control insects and diseases. The technology and performance evaluations were described in several papers in the journal Transactions of the ASABE.
The sprayer developed by Zhu and his colleagues controls output to match targeted tree structures. The two-ton sprayer can treat either a single row, or two to six rows of trees at a time. Conventional spray application technology requires excessive pesticide use to achieve effective pest control in floral, nursery, orchard, and other specialty crop productions, according to Zhu. This challenge is now overcome by the new precision sprayer, which is able to characterize the presence, size, shape and foliage density of target trees and automatically applies the optimum amount of pesticide.
Zhu and his colleagues conducted field trials on the technology's performance in six commercial nurseries in Ohio, Oregon and Tennessee. Their field experiments showed that the precision sprayer consistently applied the correct amount of chemicals despite changes in tree structure and species, and increased consistency of spray deposition uniformity on targets at different growth stages. Pest control with the new sprayer was comparable to that of conventional sprayers and reduced pesticide use.
ARS is the USDA's chief intramural scientific research agency.
Read more about this technology in the February issue of AgResearch magazine.
By Kim Kaplan
February 10, 2016
BELTSVILLE, Md., Feb. 10, 2016—Temperature extremes during shipping and elevated pathogen levels may be contributing to honey bee queens failing faster today than in the past, according to a study just published by U.S. Department of Agriculture (USDA) scientists in the scientific journal PLOS One.
"Either stress individually or in combination could be part of the reason beekeepers have reported having to replace queens about every six months in recent years when queens have generally lasted one to two years," explained entomologist Jeff Pettis with the Bee Research Laboratory in Beltsville, Maryland, who led the study. The Bee Research Laboratory is part of USDA's Agricultural Research Service.
Queens only mate in the first few weeks of life. Then they use the stored semen to fertilize eggs laid throughout their life. Queen failure occurs when the queen dies or when the queen does not produce enough viable eggs to maintain the adult worker population in the colony. Replacing queens cost about $15 each, a significant cost per colony for beekeepers.
Commercial beekeepers usually order their replacement queens already mated, and the queens are shipped to apiaries from March through October. Researchers questioned whether temperature extremes during shipping could damage the sperm a queen has stored in her body. During simulated shipping in the lab, inseminated queens exposed to 104° F (40° C) for 1-2 hours or to 41° F (5° C) for 1-4 hours had sperm viability drop to 20 percent from about 90 percent.
In real-world testing, queens, along with thermometers that recorded the temperature every 10 minutes, were shipped from California, Georgia and Hawaii to the Beltsville lab by either U.S. Postal Service Priority Mail or United Parcel Service Next Day Delivery in July and September. Researchers found that as many as 20 percent of the shipments experienced temperature spikes that approached extremes of 105.8° F and 46.4° F for more than 2 hours at a time. Those exposed to extreme high or low temperatures during shipping had sperm viability reduced by 50 percent.
"The good news is with fairly simple improvements in packaging and shipping conditions, we could have a significant impact on improving queens and, in turn, improving colony survival," Pettis said.
Assessments of the queens sent in by beekeepers for this study found that almost all of them had a high incidence of deformed wing virus; Nosema ceranae was the next most commonly found pathogen.
Beekeepers had also been asked to rate the performance of each colony from which a queen came as either in good or poor health. A clear link was found between colonies rated as better performing and queens with higher sperm viability. Poorer performing colonies strongly correlated to queens with lower sperm viability.
"We saw wide variation in both pathogen levels and sperm viability in the queens that were sent in to us, and sometimes between queens from the same apiary in July and September, so there is still more research to do. But getting queens back to lasting two years may well be one of the links in getting our beekeeping industry back to a sustainable level," Pettis said.
The Agricultural Research Service (ARS) is the U.S. Department of Agriculture's chief scientific in-house research agency. The Agency's job is finding solutions to agricultural problems that affect Americans every day from field to table. ARS conducts research to develop and transfer solutions to agricultural problems of high national priority and provide information access and dissemination to ensure high-quality, safe food, and other agricultural products; assess the nutritional needs of Americans; sustain a competitive agricultural economy; enhance the natural resource base and the environment and provide economic opportunities for rural citizens, communities, and society as a whole.