Aneuploidy among androgenic progeny of hexaploid triticale (XTriticosecale Wittmack)

Abstract

Doubled haploids are an established tool in plant breeding and research. Of several methods for their production, androgenesis is technically simple and can efficiently produce substantial numbers of lines. It is well suited to such crops as hexaploid triticale. Owing to meiotic irregularities of triticale hybrids, aneuploidy may affect the efficiency of androgenesis more severely than in meiotically stable crops. This study addresses the issue of aneuploidy among androgenic regenerants of triticale. Plant morphology, seed set and seed quality were better predictors of aneuploidy, as determined cytologically, than flow cytometry. Most aneuploids were hypoploids and these included nullisomics, telosomics, and translocation lines; among 42 chromosome plants were nulli-tetrasomics. Rye chromosomes involved in aneuploidy greatly outnumbered wheat chromosomes; in C0 rye chromosomes 2R and 5R were most frequently involved. While the frequency of nullisomy 2R was fairly constant in most cross combinations, nullisomy 5R was more frequent in the most recalcitrant combination, and its frequency increased with time spent in culture with up to 70% of green plants recovered late being nullisomic 5R. Given that 5R was not involved in meiotic aberrations with an above-average frequency, it is possible that its absence promotes androgenesis or green plant regeneration. Overall, aneuploidy among tested combinations reduced the average efficiency of double haploid production by 35% and by 69% in one recalcitrant combination, seriously reducing the yield of useful lines.

Arabinogalactan proteins improve plant regeneration in barley (Hordeum vulgare L.) anther culture

“…Culture periods longer than 18 days on the induction medium promote excess callusing with consequent low embryo formation and low conversion rate into plants (Kao et al 1991;Sriskandarajah et al 2015). Extended time in culture may induce variation at different levels among regenerants, promote clone formation-(sets of genetically identical plants), and increase the frequency of chromosome aberrations or the proportion of albino plants (APs) (Jähne et al 1991;Oleszczuk et al 2011Oleszczuk et al , 2014. Each one of those reduces the overall efficiency of androgenesis.…”

Gametocidal Factor Transferred from Aegilops geniculata Roth Can Be Adapted for Large-Scale Chromosome Manipulations in Cereals

“…Moreover, triticale is a less meiotically stable crop, compared to wheat, and that is manifested by chromosome pairing issues and tends to show a fair proportion of aneuploids among both sexually derived progenies and DH lines (Lukaszewski and Gustafson, 1987; Lelley, 2006). Oleszczuk et al (2011) karyotyped (not randomly, basing on morphology) 140 DH plants of winter triticale and observed some plants with chromosome abnormalities, such as different chromosome number (nullisomics and tetrasomics), telocentric chromosomes, and translocations. What is more, most of the plants were nullisomics for one or more rye chromosomes, and chromosome 5R was the most frequently involved, followed by 2R.…”

“…From the other point of view, the gametocidal action contributed to elimination of triticale chromosome arms (3AS, 3RS, 4RL, 7RL) and segments (distal segment of 5BL and 5RS-5RL.del). Intriguingly, some of the reports indicated that chromosome 5R is involved in induction of chromosome abnormalities (Charmet et al, 1986; Oleszczuk et al, 2011). It is also worth underlining that chromosome 5B carries the Ph1 gene locus (5BL), which enforces strictly bivalent pairing in polyploid wheat, and this makes 38T+D5BS-5BL.5RL DH lines a great germplasm for meiotic studies.…”

“…DH lines can be produced in several ways, applying distant hybridization, androgenesis, or gynogenesis (Forster et al, 2007). In triticale, generally, androgenesis is induced, using anther cultures (Ślusarkiewicz-Jarzina and Ponitka, 2003; Oleszczuk et al, 2011). This technique, in most cases, produces reasonable yields of haploids and DHs and is routinely used in triticale breeding.…”

Analysis of Yield and Yield Related Traits Variability of Winter Wheat (Triticum aestivum L.) Cv. Izolda and Double Haploid Lines

“…Tested DH lines were obtained via androgenesis from isolated anthers of Izolda cv. in in vitro culture (Konieczny et al, 2003;Oleszczuk et al, 2011).…”