The Journal of Heredity 1997:88(6):459-465
© 1997 The American Genetic Association 88:459-465
research-article |
Characterization and Breakdown of Self-Incompatibility in Field Bindweed (Convolvulus arvensis L.)
Horticulture Department, Purdue University West Lafayette, Indiana
the Faculty of Agriculture, Shinshu University Ina Nagano, 399-45 Japan
Address correspondence to Dr. Weatwood, Virginia Polytechnic Institute and State University, Department of Plant Pathology, Physiology, and Weed Science, 410 Price Hall, Blacksburg, VA 24061
Corresponding Editor: Prem P. Jauhar
Abstract
Field bindweed blotypes differ in glyphosate tolerance. Our previous studies have Indicated quantitative genetic inheritance of this trait. In order to study the genetics of these differences we must be able to make sexual crosses, however, self-crossing and backcrosslng are difficult due to self-Incompatibility (SI) In field bindweed flowers. Therefore research was conducted to characterize and overcome the SI system in field bindweed. We determined SI to be of the multiallelic, sporophytic type based on observations of pollen-stigma Interaction, and in the pattern of compatibility of F1 backcrosses to the parent biotypes. Pollen in incompatible crosses produced short pollen tubes that failed to penetrate the stigma surface. Backcrossing showed most F1 plants to be compatible with one parent, indicating dominance interactions between alleles. SI in field bindweed was successfully overcome by both bud pollination and heat treatment which exposed plants to 38°C for 2 days before pollination, however, no seeds were produced. Treatment of stigma tips with a hot soldering iron for 23 s allowed abundant pollen tube growth from selfed pollen lying in a zone adjacent to the heat-injured area. This method resulted in production of viable selfed seed at rates equal to that observed in outcrosses.