Protecting Pollinators and Crops from Pests
ARS promotes sustainable crop production by protecting crops and pollinators from pests that threaten their health and consequently reduce crop yields. More than 4,500 invasive pests damage crops, costing U.S. agriculture an estimated $30 billion annually. In addition, the risks posed to bees by invasive mites, beetles, and disease is equivalent to $15 billion in lost pollination services for fruit, nut (almond), and legume crops. The following FY 2019 accomplishments highlight several ARS advances in pollinator health and pest management research. Hyperlinked accomplishment titles point to active parent research projects.
Mite blood-feeding dogma overturned: Varroa mite feeds instead on bee fat body. Varroa mite is the greatest factor in honey bee mortality. Reassessing the feeding habits of these parasitic mites in collaboration with University of Maryland cooperators, ARS researchers in Beltsville, Maryland, found that contrary to decades of literature, varroa mites do not feed on honey bee blood (hemolymph), but instead feed on the insect’s fat body. This has important implications for using mite control strategies that involve the bee, since any anti-mite chemical, such as those that silence mite genes, would have to be delivered not to the bee hemocoel (blood system), but rather to the fat body. Since the fat body is also where a bee’s hormones are produced, it also helps to explain the mite’s devastating effects.
Small hive beetle genome sequenced. Small hive beetle eats through honey bee hive comb, honey, pollen, and brood, and is an important worldwide parasite of social bee colonies. ARS scientists in Beltsville, Maryland, sequenced and characterized the beetle genome and found it contains unique detoxification genes. In addition, sequencing described the proteins used by these beetles to identify each other and honey bee colonies by smell, a critical target for attempts to trap beetles. The study provides new insights into the genomic basis for local adaption and invasiveness in the beetle and a blueprint for control strategies that target this pest without harming their honey bee hosts.
Protecting sorghum from sugarcane aphid
Monitoring and predicting sugarcane aphid populations lowers cost of treatment. The United States typically produces more than 400 million bushels of sorghum valued at more than $1.5 billion on more than 6 million acres. Sugarcane aphid is an invasive pest of sorghum and severely threatens the economic viability of sorghum production in Kansas, Oklahoma, and Texas, which together account for about 82 percent of grain sorghum production nationwide. Effective insecticides and resistant hybrids have been identified, thus helping to reduce damage, but monitoring sugarcane aphid infestations in sorghum fields is essential to optimal management. ARS scientists in Stillwater, Oklahoma, developed sugarcane aphid infestation monitoring methods based on acquisition and analysis of multispectral imagery obtained from an aerial platform. This innovative spatial pattern system can delineate spatially variable infestations of sugarcane aphid in sorghum fields, detect changes in spatial extent and infestation intensity, and differentiate between aphid damage and other crop stress events such as drought. The ARS research facilitated development of novel methods for monitoring sugarcane aphid infestations in sorghum fields that are suitable for making insecticide control decisions at the whole-field and intrafield scales. The research results have been published and adoption of recommendations could reduce the number of improperly timed or unnecessary insecticide applications, which would be an economic benefit to sorghum growers.
Sorghum lines resistant to sugarcane aphid and greenbug released. Sugarcane aphid is a new invasive pest of sorghum and causes severe damage to sorghum that results in substantial production losses (i.e., $742.7 million in 2015). ARS scientists in Stillwater, Oklahoma, screened germplasm resources for resistance to this devastating aphid through evaluation of a large collection of sorghum germplasm, leading to the identification of resistant materials and subsequent incorporation of this genetic resistance through traditional breeding. Two breeding lines have been released: STARS 1801S has genetic resistance to both sugarcane aphid and greenbug, and STARS 1802S has resistance to sugarcane aphid and head smut disease. These new resistant sources are already available to the sorghum community and will directly contribute to genetic improvement of sorghum for crop protection and can successfully help sorghum producers safeguard their crops from this severe aphid pest.
ARS facilitates registration of chemical pesticides for specialty crops. Specialty crops, including vegetables, fruits, nuts, and ornamentals, have a very high value per acre, but their small acreages compared with row crops can be a major deterrent to pesticide registrants to label their products for these uses. The Interregional Research Project Number 4 (IR-4 Project) is the primary entity in the United States that facilitates registrations of conventional pesticides and biopesticides for specialty crops by developing and submitting data that are required by the Environmental Protection Agency for registration. In collaboration with the national IR-4 Project and cooperating universities and crop protection industries, ARS researchers in eight locations conducted field trials and pesticide residue analyses in 2019 and developed data for food, floral, and nursery crops. The researchers conducted 55 and 96 field trials for food crops and ornamentals, respectively. In addition, pesticide residue analysis research was performed on 40 sample sets of food crops at two ARS laboratories. In 2018, ARS data supported the registration of 151 crop uses for 4 fungicides and 1 herbicide that are now available to specialty crop growers to reduce losses from pests, diseases, and weeds. The IR-4 Project contributes to an increase of $7.8 billion dollars annually to the U.S. Gross Domestic Product and supports more than 100,000 jobs.
New precision sprayer for specialty crops. ARS scientists in Wooster, Ohio, developed an innovative laser-guided sprayer to help specialty crop growers apply precise amounts of agrochemicals. The system uses high-speed laser scanning technology to image the tree structures and then an air-assisted variable-rate spraying system controls the spray outputs to match targeted tree canopies. The Smart-Apply Intelligent Spray Control System has been licensed to and commercialized by Smart Guided Systems LLC in Indianapolis, IN. Since the technology acquisition in April 2019, the company has retrofitted existing 20 sprayers throughout the U.S., with orders for approximately 40 additional units. The growers represent nearly 750 sprayers in total, an the company expects all sprayers to be converted over time. The crops represented in the 20 units so far are: citrus, nursery, apple, pear, pecan, and Hazelnut. Chemical savings by using the Intelligent Spray Control System range from 36-90% depending on crop type and age of tree. The Intelligent Spray Control System was just recognized by American Society of Agricultural and Biological Engineers (ASABE) as a top 50 new product innovation winner (AE50) and was selected as the winner of the prestigious 2020 Davidson Prize, awarded to the top AE50 winning products judged to be the most innovative and most likely to have a significant impact on agricultural production, efficiency, or safety. Further, the system was selected by World Ag Expo as the Top-10 new product for 2020.