Source: UNIV OF ARKANSAS submitted to NRP
EFFECT OF INSECTICIDES ON HONEY BEES AND OTHER POLLINATORS OF CROPS AND FRUITS IN ARKANSAS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
1013964
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 3, 2017
Project End Date
Sep 30, 2022
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIV OF ARKANSAS
(N/A)
PINE BLUFF,AR 71601
Performing Department
Department of Agriculture
Non Technical Summary
Pollination is an essential process in the production of a myriad of fruits and vegetables. In the agricultural environment, bees are the most important pollinators. However, many farmers are noticing a lack of pollinators throughout their farmlands. They will survive, thrive and reproduce when their habitat provides their requirements such as food, nest sites and appropriate nest materials. The objectives of the project are to identify major and minor pollinator genera and species, and pollinators' abundance and species richness in cucumber, watermelon and sweetpotato fields in Arkansas. We will further investigate the influence of pesticides on pollinators' abundance and species richness in cucumber, watermelon and sweetpotato fields in Arkansas.
Animal Health Component
30%
Research Effort Categories
Basic
60%
Applied
30%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
21130101130100%
Goals / Objectives
Pollinators, especially bees are keystone organisms in most terrestrial ecosystems. They will survive, thrive and reproduce when their habitat provides their requirements such as food, nest sites and appropriate nest materials. They are essential for maintaining the integrity, productivity and sustainability of many types of ecosystems. Without them, many fruit- and seed-eating birds and some mammals would have a less varied and less healthy diet.Most pollinators visit flowers to get pollen and/or nectar, which they use to feed themselves, their offspring and one another at times. When pollinators forage pollen and/or nectar, they pollinate plants by transferring or crossing pollen from flower to flower. Honey bees, native bees and other pollinators play important roles in crop, vegetable and fruit production (Chaplin-Kramer, et al. 2014; Foley, et al., 2011; Smith, et al., 2015). Therefore, their pollinating roles are essential to insure fertilization and to increase the size and quality of crops at harvest because agricultural fields need up to 78% of crop and vegetables depended on the pollinators in temperate-zone and 94% in tropical-zone (Ollerton, et al., 2011).Managed honey bees, which are general pollinators in the U.S., have been in a severe decline from about 6 million colonies in 1947 to 2.62 million colonies in 2013 (USDA, 2013). In managed honey bees (Apis mellifera), in general, beekeepers reported 15 to 20% colony death after the winter season prior to 1980 in the U.S. However, in 2007 and 2008 colony death reached 31 to 36% (van Engelsdorp et al., 2008). During this period, commercial beekeepers reported 30 to 90% colony loss. Since the mid-1980s, introduced mites such as tracheal (Acarapis woodi) and Varroa mite (Varroa destructor) made beekeeping more laborious and more likely to fail. Especially, Varroa mite infestation results in shortened lifespan of over-wintered honey bees, eventually ending in colony death. Diseases caused by the fungal parasite Nosema and viruses such as Israeli Acute Paralysis Virus, Kashmir Bee Virus and Deformed-Wing Virus have severe negative impact on honey bees (Cox-Foster, et al., 2007). Native bees and other pollinators may not be exceptional in a similar situation.Another factor that has been suggested as being related to honey bee declines is insecticides. The use of insecticides and other chemicals that have been applied to control plant diseases and pests in the field resulted in declining population of pollinators by killing them directly, impairing behavioral perception, lowering foraging rate and interfering with homing ability (Vandam, et al., 1995; Bortolotti, et al., 2003; Colin, et al., 2004; Decourtye, et al., 2004; Decourtye, et al., 2005). The effects of sub-lethal doses to various pollinator groups lowered survival rate during early stage of the pollinator.Abundance means the number of individuals of each species collected per unit of time. Species richness means that the number of bee species present at a site. These two indicators will provided us information on numbers of individuals of different species per unit time and species richness. These data will allow us to compare both overall availability of bee pollinators among the areas and the relative abundance of native bees or honey bees within the farmland.Climate change (Sparks & Yates, 1997; Deutsch et al., 2008; Morris et al., 2008; Heard & Hendrikz, 1993; Stone, 1994; Rader et al., 2013), land-development and partial fragmentation of farmlands and forests near agricultural fields have influenced the negative impact on pollinators (Mandelik et al., 2012) because these changes result in mis-timing for food resources and pollination, as well as loss of nesting habitat.Currently various pest management techniques such as better organic or inorganic chemicals have been introduced to help agricultural productivity. But agricultural success requires the presence of pollinators in the agricultural field. Pesticide use, however, can negatively affect bee abundance and species richness in agriculturalsettings (Kevan 1975, Johansen 1977, Plowright et al. 1978, Plowright & Rodd 1980, Gels et al. 2002, Shuler et al. 2005). Pesticide use had a slight negative impact on bee abundance, but only three studies had relevant data on pesticide use and the effect was not significant. Some studies have shown that bee species differ widely in susceptibility to pesticides, so that data on toxicity to honey bees may not be accurate for all bee species (Thompson & Hunt 1999). Scott-Dupree et al. (2009) investigated the toxicity of several widely used pesticides (imidacloprid, clothianidin, deltamethrin, spinosad, and novaluron) on three different bee species (Bombus impatiens, Megachile rotundata, and Osmia lignaria) and found as much as a 65-fold difference in sensitivity among species. The impact of herbicides on bee abundance and diversity is not clear so far. In Arkansas, no previous studies have examined herbicide use on bee abundance and diversity.The objectives of the project are to identify major and minor pollinator genera and species, and pollinators' abundance and species richness in cucumber, watermelon and sweetpotato fields in Arkansas. We will further investigate the influence of pesticides on pollinators' abundance and species richness in cucumber, watermelon and sweetpotato fields in Arkansas.
Project Methods
Objective 1: Identify pollinator genera and species and quantify species abundance and richness in cucumber field in Arkansas.Data on pollinator identification, visitation and abundance on cucumber field will be collected at the UAPB Agricultural Experiment Station in Pine Bluff, Arkansas, during the growing seasons of the project. Sampling will be conducted during the peak flowering period of the cucumber in each of four years.All collections will be made between 9:00 and 15:00 on days when the air temperature exceeds 15°C. Pollinators will be netted flying near cucumber blossoms or landing on cucumber blossoms, which means our measure of abundance will be closely correlated with visitation rate. The PI developed two different collecting methods (Grubb, 1977; Brittain et al., 2009), both of which provide information on pollinator species richness, and one of which provides information on pollinator abundance.General collecting: consists of walking along rows of cucumber field and netting any pollinators we observe landing on or flying around cucumber blossoms. Honey bees will not be collected during this type of survey as the objective is to characterize the pollinator species richness in the experimental field.Time-trial collecting: consists of collecting all pollinators including honey bees during 15-minute intervals. For 15 minutes the PI or a student will walk down a single, 100 m row of the cucumber field and collect all pollinators observed. The 15-minute timed collections give us information on pollinator abundance (numbers of individuals of different species) per unit time as well as species richness. Timed collections will allow us to compare both overall pollinator abundance among fields as well as the relative abundance of native vs. honey bees within fields.For both methods, pollinators will be killed in killing jars, stored in labeled collecting vials, and later mounted on insect pins. For all collections we will record locality (and latitude/longitude), time of day, weather conditions (temperature, cloud cover, wind speed), and collector identification. Specimens will ultimately be labeled with a unique barcoded label (containing a unique specimen identification code) which also includes standard insect label information, such as state, county, locality, date, collector and host-plant. Specimens will be idetnified to species using relevant taxonomic keys to bees of eastern North America (e.g.Mitchell 1961a,b; Bouseman & LaBerge 1978; LaBerge 1971, 1978; LaBerge & Bouseman 1973, Rehan & Richards 2008), the Discover Life website, or by comparison with authoritatively identified specimens in the University of Arkansas at Pine Bluff Insect Collection and Sunflower project specimen (Posey et al., 1986).In many pollinator diversity studies, species identification is a major obstacle because ofthe large number of species, lack of good reference material, or lack of taxonomic expertise. The PI was trained in bee species identification at the "Bee Workshop" at the U.S. Geological Survey Patuxent Wildlife Research Center and has 10 years' experience identifying bees of Arkansas.Objective 2: Identify pollinator genera and species and quantify species abundance and richness in watermelon field in Arkansas.Data on pollinator identification, visitation and abundance on watermelon field will be collected at the UAPB Agricultural Experiment Station (Lonoke, Arkansas) during the growing seasons of the project. Sampling will be conducted during the peak flowering period of the watermelon in each of four years.All collections will be made between 9:00 and 15:00 on days when the air temperature exceeds 15° C. Pollinators will be netted flying near watermelon blossoms or landing on watermelon blossoms, which means our measure of abundance will be closely correlated with visitation rate. All collecting methods will be the same as those described above.Objective 3: Identify pollinator genera and species and quantify species abundance and richness in sweetpotato field in Arkansas.Data on pollinator identification, richness, abundance, and visitation patterns on sweetpotato will be collected at the University of Arkansas Pine Bluff Agricultural Experiment Station during the 2017-2022 growing season. Data collection will be conducted during July, which is the peak flowering period, and in early August each year.During the peak flowering period, 5-minute insect net swipe samplings will be taken during the 3-year project period. Meanwhile, bowl traps with soap water will be set up, and trapped insects will be collected. Each bowl trap will be located from 1 to 25 flower heads. Individual bee visitations will be recorded by species when possible, and the total number of bees will be counted during the observation period. When the appearance of the bees is observed, pictures will be taken for identification.The PI will use current traps to monitor once a week when sweetpotatos are in the field. The sweetpotato is less attractive to pollinators than other flowering plants so that we are going to focus on the species of underground genera at the sweetpotato field.All collections will be made between 9:00 and 15:00 on days when the air temperature exceeds 15° C. When the number of the sweetpotato leaves reaches 10 or more per plant, we will collect 1 kg of soil from the field every week and will identify major and minor genera of underground species.Objective 4: Determine the effect of pesticides on pollinators in cucumber, watermelon and sweetpotato fields in Arkansas.We will divide insecticide use into two ways. The importance of surrounding habitat on pollinator species richness and/or abundance has been shown in a number of crop systems (Kremen et al. 2002). First, we will survey local growers to personally characterize the farm management practices that they employ. Three options include organic, IPM, and conventional.Second, insecticide use can negatively affect pollinator abundance and species richness in agricultural fields and surrounding habitats (Shuler, et al. 2005; Winfree et al. 2009). We will collect insecticide use records from local growers on an annual basis and compare relationship of the environmental impact between insecticide use and abundance/richness of the pollinators.Farmers in the project will participate in keeping in their farming practice record of the pesticide and herbicide, monitoring and comparing bee health, and collecting pollinators in their fields during blooming period. Guidelines on insecticide use will be developed for farm management, and recommendations will be formed on how farmers can sustainably manage and preserve the biodiversity of pollinators around specialty crops and vegetables. The PI will form an Extension conference for local farmers who may need more pollinators in their field so that they can avoid the extra cost of honey bee rentals and to inform them on how to use honey bees to assure quality pollination in the field.