an efficient method for producing doubled haploid plants of date palm ( phoenix dactylifera l.) was established using in vitro colchicine treatment of anthers. to this study male inflorescences were harvested in the appropriate developmental stage. separated anthers after one day cold (4°c) pretreatment, in uninucleate stage of microspore were transferred to the modified y 3 medium containing d...

Despite a great deal of theoretical attention, we have limited empirical data about how ploidy influences the rate of adaptation. We evolved isogenic haploid and diploid populations of Saccharomyces cerevisiae for 200 generations in seven different environments. We measured the competitive fitness of all ancestral and evolved lines against a common competitor and find that in all seven environm...

Doubled haploids of carnation (Dianthus caryophyllus L.) were obtained by pseudofertilized ovule culture. Emasculated ̄ower buds of carnation were pollinated with pollen inactivated by Xray irradiation. After 2±3 weeks, the ovaries were explanted and were cultured on solid MS medium containing 2 mM NAA, 2 mM BAP and 6% sucrose. Regenerated plants(R0) were morphologically different from the moth...

The terms 'haploid' and 'diploid' that describe single (n) and double (2n) chromosome sets in cells were coined by the Polish-German botanist Eduard Strasburger and originate from the Greek terms haplóos meaning 'single' and diplóos meaning 'double'. The term 'ploidy' was subsequently derived to describe the total chromosome content of cells. Consequently, the term 'euploid' refers to a chromos...

A supposed sporulation-deficient mutation of Saccharomyces cerevisiae is found to affect mating in haploids and in diploids, and to be inseparable from the mating-type locus by recombination. The mutation is regarded as a defective a allele and is designated a*. This is confirmed by its dominance relations in diploids, triploids, and tetraploids. Tetrad analysis of tetraploids and of their spor...

Successful haploid induction in loquat (Eriobotrya japonica (Thunb.) Lindl.) through in situ-induced parthenogenesis with gamma-ray irradiated pollen has been achieved. Female flowers of cultivar 'Algerie' were pollinated using pollen of cultivars 'Changhong-3', 'Cox' and 'Saval Brasil' irradiated with two doses of gamma rays, 150 and 300 Gy. The fruits were harvested 90, 105 and 120 days after...