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Biology subjects

Auer, C.

Publications and source records attributed to Auer, C..

2 recordsLinked to original sources

Camelina (Camelina sativa L. Crantz) Crop Performance, Insect Pollinators, and Pollen Dispersal in the Northeastern US.

Camelina sativa (camelina) is an oilseed crop in the Brassicaceae that has been genetically engineered for the production of biofuels, dietary supplements, and other industrial compounds. Cultivation in North America is both recent and limited, so there are gaps in knowledge regarding yield, weed competition, and pollen-mediated gene flow. For these experiments, camelina SO-40 was grown for three years without weed control. Spring-sown camelina was harvested at 80-88 days with [~]1200 growing degree days (GDD) with yields of 425-508 kg/hectare. Camelina yields were the same with or without weeds, showing competitive ability in low-management conditions. Crop failure in 2015 was associated with delayed rainfall and above-average temperatures after seeding. Camelina flowers attracted pollinating insects from the Hymenoptera, Diptera, Lepidoptera, and Coleoptera. Hymenoptera included honey bees (Apis melifera), mining bees (Andrenidae), sweat bees (Halictidae), bumble bees (Bombus spp.) and leaf cutter bees (Megachilidae). Insect visitation on camelina flowers was associated with modest increases in seed yield. Honey bees comprised 28-33% of all pollinators and were shown to carry camelina pollen on their legs. Air sampling showed that wind-blown pollen was present at low concentrations at 9 m beyond the edges of the field. These experiments demonstrated for the first time that camelina pollen dispersal could occur through honey bees or wind, although bee activity would likely be more significant for long-distance gene flow.

plant biology↗

Reducing Pollen Dispersal using Forest Windbreaks.

The adoption of genetically engineered (GE) crops has created a demand for practical methods to mitigate pollen dispersal and gene flow. The goal of this project was to measure the ability of a narrow forest windbreak to reduce downwind pollen fluxes from switchgrass (Panicum virgatum L.), a North American grass and model biofuels feedstock. Switchgrass fields were established in two identical plots where one had a forest windbreak and the other was in an open (control) site. Switchgrass reproduction, pollen dispersal, wind speed, and wind direction were measured over two years. Daily release of switchgrass pollen peaked at 11:00-13:30 during a flowering period that lasted about 44 days. The best estimate for switchgrass pollen source strength (PSS) was 141 x 109 pollen/season/hectare for fields planted at commercial densities. The forest windbreak consistently decreased downwind switchgrass pollen concentrations by 333-20,000 fold compared to the control plot which had a 58-77 fold decrease due to downwind distance alone. These results suggest that forest windbreaks could be used as a barrier to reduce pollen dispersal and gene flow from switchgrass and other crops.\n\nResearch HighlightA narrow forest windbreak greatly decreased downwind pollen concentrations from a switchgrass field suggesting that trees can reduce crop gene flow, enhance coexistence between farming systems, and provide ecosystem services.

plant biology↗