HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Baluch, S. J. Articles by Cleveland, R. W. Search for Related Content PubMed Articles by Baluch, S. J. Articles by Cleveland, R. W. Agricola Articles by Baluch, S. J. Articles by Cleveland, R. W.

Pollen Germination and Tube Growth after Selfing and Crossing Coronilla varia L¹

Crownvetch, Coronilla varia L., is relatively self-incompatible. Plants selected to represent the full range of self-fertility of a large sample of C. varia L. ‘Penngift’ were used in greenhouse experiments to locate the site or sites of incompatibility of self-pollinations. Pollen germination and pollen tube growth in pistils after self- and cross-pollinations were observed employing UV fluorescence microscopy.

Pollen germination on the stigma and pollen tube penetration of the style occurred within the first 12 hours after self- and cross-pollination. Pollen tubes reached ovaries within 24 hours for both types of pollination.

In one experiment, the average number of germinated pollen grains on stigmas was significantly higher after crossing than after selling. However, this relationship between the two types of pollination was not consistent over the plants studied. For most plants, pollen germination on stigmas after cross-pollination was about twice that after self-pollination. This suggested that self-incompatibility existed on the stigma. In the second experiment, using a different pollen source, the average number of germinated pollen grains on the stigma after crossing was not significantly different from that after selfing and the site of incompatibility seemed to be in the style.

Pollen tube behavior in the ovary was the same for selfing and crossing in both experiments. For selfing, less ovules matured as seed than were penetrated by pollen tubes. Thus, both fertilization failure and post-fertilization ovule abortion could have affected the amount of seed set after selling.

Pollen germination and pollen tube behavior were the same in flowers from excised stems and stems growing on plants.

Key Words: Crownvetch • Microgametophyte • Incompatibility • UV Fluorescence microscopy

² Graduate Trainee in Genetics and Associate Professors of Plant Breeding, respectively, Pennsylvania State University, University Park, Pa. 16802.

Received for publication July 3, 1972.