Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Life Sciences
Morphology And Distribution Of Petiolar Nectaries In Ipomoea (Convolvulaceae), Kathleen H. Keeler, Robert B. Kaul
Morphology And Distribution Of Petiolar Nectaries In Ipomoea (Convolvulaceae), Kathleen H. Keeler, Robert B. Kaul
School of Biological Sciences: Faculty Publications
The distribution of petiolar nectaries in 24 species of Ipomoea was investigated. Petiolar nectaries were found on 12 species (8 new reports, 4 confirmations of previous reports) and quoted from the literature as being found on 3 other species; they were absent from 9 species investigated. The structure of petiolar nectaries in the genus ranges from simple beds of superficial nectar-secreting trichomes (1 species), to slightly recessed "basin nectaries" (8 species), to "crypt nectaries," which are structurally the most complex extrafloral nectaries known (3 species). (Structures were not determined for 3 species.) Petiolar nectaries are present in all subgenera, but …
Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler
Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler
School of Biological Sciences: Faculty Publications
Frequencies of plants with extrafloral nectaries were determined for two elevations in Jamaica. Extrafloral nectaries were found on 0.28 of the plants at sea level (Happy Grove, Portland) and 0.00 of the plants at 1310 m (Whitfield Hall, St. Thomas). Ant abundance, as indicated by discovery of and recruitment to baits, was greater at the lower elevation site. However, despite the apparent absence of plants with extrafloral nectaries, there were abundant ants at 1310 m.
Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler
Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler
School of Biological Sciences: Faculty Publications
Extrafloral nectaries (EFNs) are glands on a plant, not involved in pollination, that produce solutions containing sugars (and other compounds). Long noted by morphologists, EFNs have recently been observed to be part of ant-plant mutualisms. The function of EFNs appears to be to attract aggressive insects, especially ants, which by disturbing or preying upon herbivores, reduce damage to the plant (Janzen, 1966a,b; Elias and Gelband, 1975; Keeler, 1975, 1977; Bentley, 1976, 1977a,b; Schemske, 1978; Tilman, 1978; Inouye and Taylor, 1979; Pickett ad Clark, 1979). Furthermore, they constitute an unusual plant defense against herbivores: at EFNs plants employ ants as a …
Nocturnal Pollination Of Abronia Fragrans (Nyctaginaceae), Kathleen H. Keeler
Nocturnal Pollination Of Abronia Fragrans (Nyctaginaceae), Kathleen H. Keeler
School of Biological Sciences: Faculty Publications
Abronia fragrans Nutt. (Nyctaginaceae) is a white-flowered herb of dry sandy soils from Idaho and South Dakota to Arizona and Texas. It can be readily observed to fit a night-blooming, moth-pollinated syndrome (Faegri and van der Pijl, The principle of pollination ecology, 1971). This does not seem to have been noted: in all references to A. fragrans we could find, the only indication of nocturnal anthesis was the comment of Nelson (Handbook of Rocky Mountain plants, 1969), who observed that the fragrance was more noticeable at night. Tillett (Brittonia 19:299-327, 1967), working on Pacific species, suggested that the pink …