Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/25/2002
Publication Date: 8/26/2002
Citation: PALMER, R.G., WESTIN, E., SCOTT, M.P., HORNER, H.T., BROWN, A. NECTAR COMPOSITION OF WILD PERENNIAL GLYCINE (SOYBEAN) SPECIES. MEETING ABSTRACT. 2002. p. 382. Abstract No. 704.
Technical Abstract: The genus Glycine contains the cultivated annual soybean G. max, the wild annual soybean G. soja, and about 21 wild perennial Glycine species. The perennials are largely indigenous to Australia, but are found in Papua New Guinea, Timor, Philippines, Japan and Taiwan. Outcrossing by insects occurs at a very low frequency (<1%) in the cultivated species, between <1% to 20% in the wild annual species, and can exceed 50% in certain wild perennial species. The objective was to determine nectar composition (glucose, fructose, and sucrose) from flowers of glasshouse-grown wild perennial plants. Nectar samples were collected from 105 accessions representing 15 recognized species and 6 other types. Sugars were analyzed by spectrophotometric enzyme assays. Sugar ratios were the most meaningful for comparative purposes. The ratio of glucose: fructose: sucrose was relatively constant across time (10:00 to 17:00 hours) and across days. Variation among species was most noticeable for sucrose, as low as 50% to as high as 90%, with the glucose: fructose ratio relatively constant. Within a species, most accessions presented similar sugar ratios. The extreme ratios were from accessions that were the most diverse in growth habit, and divergent for molecular markers. The information gained from the floral nectar composition of the wild perennial species will guide research for nectar composition-outcrossing associations in the cultivated species. The overall goal is to produce large quantities of F1 hybrid seed for plant breeding studies, and for commercial hybrid seed production. Unfortunately, there is a paucity of data on the native insects that effect outcrossing in the wild perennial species.