Determination of ploidy level in “Mitchell” Petunias

• Published in: Plant science (Limerick) Vol. 65; no. 1; pp. 119 - 124
• Main Authors: Kamo, Kathryn K., Griesbach, Robert J.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 1989; Elsevier Science
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Cytogenetics; Fundamental and applied biological sciences. Psychology; Generalities. Genetics. Plant material; Genetics and breeding of economic plants; Genetics of eukaryotes. Biological and molecular evolution; microfluorimetry; ploidy determinations; Pteridophyta, spermatophyta; Vegetals and fungi; “Mitchell” Petunias; microfluorimetry; “Mitchell” Petunias; ploidy determinations; Ploidy; Tissue culture; Chromosomic number; Fluorescence spectrometry; Haploidy; Regeneration; Diploidy; Petunia; Dicotyledones; Angiospermae; Flower crop; Spermatophyta; Solanaceae; Chimerism; Chloroplast; Cultivar
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/0168-9452(89)90214-8

Mitchell Petunia plants were analyzed for their level of ploidy by: (1) counting the number of chromosomes in root tips; (2) counting the number of chloroplasts per guard cell pair; and (3) using fluorescence microscopy to measure the amount of DNA stained with Hoechst 33258. The majority of plants propagated through tissue culture were chimeric rather than either completely diploid or haploid, and we have shown that one cannot distinguish between haploids and chimeric haploid/diploid plants based on chloroplast counts. One must use either chromosome counts or microfluorimetry to distinguish between these.