Search National Agricultural Library Digital Collections

NALDC Record Details:

Analysis of Ploidy Level and Its Effects on Guard Cell Length, Pollen Diameter, and Fertility in Hydrangea macrophylla

Permanent URL:
http://handle.nal.usda.gov/10113/17762
Abstract:
Ploidy level was estimated in Hydrangea macrophylla (Thunb) Ser. using flow cytometry. For H. macrophylla ssp. macrophylla, 42 diploid and 19 triploid cultivars were identified. All 14 H. macrophylla ssp. serrata (Thunb.) Makino cultivars tested were diploids. Somatic chromosome counts confirmed the ploidy of three diploid (2n = 2x = 36) and three triploid (2n = 3x = 54) cultivars. Stomatal guard cell length and pollen diameter of H. macrophylla ssp. macrophylla diploid cultivars were smaller than those of triploid cultivars. However, because the range of measurements for the diploids overlapped that of the triploids, neither guard cell nor pollen measurements are recommended for determining ploidy of H. macrophylla cultivars. Fertility was estimated using pollen staining and controlled pollinations. Stainable pollen for triploid cultivars averaged 63% and ranged from 25% in 'Masja' to 85% in 'Marechal Foch'. Viable seed was obtained when four triploid cultivars were used as pistillate or staminate parents in controlled pollinations to diploid H. macrophylla ssp. macrophylla cultivars. A bimodal distribution of pollen sizes, which is suggestive of unreduced gamete production, was observed in one cultivar; however, more detailed genetic and cytologic studies are needed to elucidate the mechanism behind triploid formation in H. macrophylla taxa.
Author(s):
Jones, K.D. , Reed, S.M. , Rinehart, T.A.
Subject(s):
Hydrangea macrophylla , ornamental woody plants , nursery crops , guard cells , length , pollen , plant fertility , flow cytometry , cultivars , chromosome number , stomata , diameter , diploidy , triploidy , germ cells
Format:
p. 483-488.
Note:
Includes references
Source:
HortScience : a publication of the American Society for Horticultural Science 2007 June, v. 42, no. 3
Language:
English
Year:
2007
Collection:
Journal Articles, USDA Authors, Peer-Reviewed
File:
Download [PDF File]
Rights:
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.