Comparison of Plant DNA Contents Determined by Feulgen Microspectrophotometry and Laser Flow Cytometry

Abstract

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Determination of ploidy level and nuclear DNA content in blueberry by flow cytometry

“…Thus the genome size (in million base pairs, Mbp) can be estimated as 608 Mbp/haploid genome by assuming that 1 pg of nuclear DNA has 965 Mbp (Bennett and Smith 1976). This estimate for blueberry is almost four times greater than that found for Arabidopsis (Arumuganathan and Earle 1991 a), five times smaller than that estimated for corn (Michaelson et al 1991), almost half the size of the tomato genome (Arumuganathan and Earle 1991a), and substantially larger than the genome sizes of fruit species such as papaya, mango, apricot, sweet cherry, peach, orange and raspberry (Arumuganathan and Earle 1991a).…”

“…The application of flow cytometry to nuclei stained with propidium iodide has been directly compared with more tedious traditional approaches to measuring plant cell DNA content, and this newer approach has been found to give equivalent results (Michaelson et al 1991). Chromosome number has often been found to be significantly correlated with nuclear DNA content (Verma and Rees 1974;Black and Beckman 1983).…”

Characterization of hybrid seedlings from crosses of <i>Nicotiana stocktonii</i> Brandegee×<i>N. tabacum</i> L. and <i>N. stocktonii</i>×progenitors of <i>N. tabacum</i>

“…sylvestris, and N. stocktonii×N. tomentosiformis hybrid seedlings and each hybrid parent; the leaves were chopped off and macerated in ice-cold buffer (Michaelson et al 1991). The macerated tissue was filtered through a 25 mm nylon mesh.…”

High levels of the cytokinin BAP suppress programmed cell death in hybrid tobacco cells (Nicotiana suaveolens*N. tabacum) expressing hybrid lethality

“…For cytometric analysis, nuclei were isolated from hybrid cells cultured with a standard level or high levels of BAP for 3 days at 28°C by chopping in ice-cold buffer (Michaelson et al 1991) and filtering through a 70 and a 20 mm nylon mesh. The nuclei were collected from the filtrate by centrifugation for 5 min at 2500 rpm and suspended in FACSFlow sheath fluid (Becton Dickinson) supplemented with 250 mM SYTOX Green.…”