Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: April 1, 2007
Publication Date: June 24, 2007
Citation: Hanlin, S.J., Mcclurg, S.G., Gardner, C.A. 2007. Insect Pollination at North Central Regional Plant Introduction Station – Past and Present. In: Proceedings of the 9th International Pollination Symposium on Plant-Pollinator Relationships - Diversity in Action. Technical Abstract: The North Central Regional Plant Introduction Station, or NCRPIS, is a joint venture among USDA-ARS, the Agricultural Experimental Stations of the 12 North Central States, and Iowa State University (ISU). As a component of the National Plant Germplasm System (NPGS), NCRPIS is dedicated to the conservation and utilization of plant genetic resources. The station was established in 1948 as one of four regional stations in the United States.  NCRPIS collections include over 49,500 accessions of 1860 species representing ca 340 genera distributed among five curatorial projects. Controlled pollination of individual plant accessions maintained at NCRPIS is necessary in order to preserve the original genetic profile of the population and its inherent diversity. At NCRPIS, insect pollinators are added to caged accessions of plant taxa that are more effectively and economically pollinated by insects than by hand; these include Brassica and other oilseed crops, miscellaneous umbels, wild-type sunflowers, vegetables such as cucurbits, and some ornamental and medicinal plant species. Historical development of controlled insect pollination at NCRPIS will be described, including development of equipment and other technologies used from 1957 to the present. These developments facilitated pollination by honeybees, bumblebees, Osmia bees, alfalfa leafcutting (ALC) bees, and flies on many plant taxa. Controlled insect pollination was initiated in 1957, when honey bees alone were used to pollinate cages of carrots, beets, celery, and onion , and has progressed to 2006 when ca 1100 accessions of many taxa were pollinated in cages by five distinct pollinators Prior to 1986, curatorial and farm staff performed all honey bee tasks. In 1986, the first USDA-ARS technician (Bill Hotchkiss) was hired to manage the honey bees under the supervision of entomologist R.L. Wilson,(1980–2000). This position was filled by Craig Abel (1988–1998), who in addition to supplying honey bees for ca 800 field cages, initiated a strong program of pollinator research with the support of Wilson. Since 1999, Steve Hanlin has supplied high quality nucs of honey bees and implemented use of ALC bees with assistance from Sharon McClurg (1984-present). Use of student workers has been essential to the success of the controlled pollination program. Current insect pollinators used at NCRPIS: Honey bees (Apis mellifera) have been utilized at NCRPIS since 1957. They are placed in ca 800 cages per year, year round; domiciles (containing 2000 to 4000 bees) can be used in multiple cages throughout the growing season. Traditionally honey bees are used to pollinate many different plants and for honey production; at NCRPIS they are used on many plants but honey produced is fed back to the bees. Honey bees forage best at 15 to 32 C (60 to 90 F). Rearing is well established but costly due to the equipment and amount of continuing care required. Bumblebees (Bombus impatiens) have been utilized at NCRPIS since1989. They are used in ca 10 cages per year, year round; domiciles (with ca 50 bees) can be reused in other cages. Traditionally Bombus are used to pollinate many different plants; at NCRPIS they are used mainly for ornamentals with trumpet-shaped flowers. Bumblebees will work in rainy, cool, windy weather at 13 to 32 C (55 to 95 F); they are active for many hours each day. Rearing trials at NCRPIS proved difficult, so commercial colonies are used which are expensive to purchase. Osmia (O. cornifrons and O. lignaria) have been utilized at NCRPIS since 1992. They are used in ca 200 cages annually, April to June; domiciles (with ca 40 bee cells) can not be relocated from one cage to another. Traditionally Osmia were used for early blooming fruit trees; at NCRPIS they are used for early season Brassica, miscellaneous umbels and ornamentals. Osmia forage best at 10 to 30 C (50 to 85 F). Rearing is established, not costly; Osmia are preferred as they are non aggressive. Houseflies or Musca domestica and Blue bottle flies or Calliphora sp., have been utilized at NCRPIS since 1980. Flies (ca 200 pupae per cage) are used in ca 40 winter-spring greenhouse cages and ca 80 summertime field cages and are replenished in cages weekly due to short life span. Traditionally flies are not used as pollinators; at NCRPIS we have found addition of flies increases successful pollination of many umbels. Flies work at 21 to 32 C (70 to 90 F), but not in rainy weather. Rearing is well-established; pupae are low cost to purchase. Alfalfa leafcutting (ALC) bee (Megachile rotundata) have been utilized at NCRPIS since 2004. ALC (20 to 40 bees per cage) are used in ca 40 greenhouse cages and ca 200 field cages. ALC live a variable length of time in cages depending on time of year and crop. Traditionally ALC were used to pollinate forage legumes; at NCRPIS we have used ALC on a wide variety of genera which have small to medium size flowers of a “flat or open” nature. ALC seem to work best at 26.5 C (80 F) or above in dry conditions, and do not work well in cooler wetter weather. ALC rearing is established, bees are low cost and require little care once they have emerged from leaf cells.