Induction of microspore embryogenesis in cultured anthers of hordeum vulgare. The effects of ammonium nitrate, glutamine and asparagine as nitrogen sources

Abstract

Improvement of the yield of green plants was obtained by decreasing the concentration of ammonium nitrate in the culture medium and using glutamine as a nontoxic nitrogen source. Embryoids developed directly from the microspores on such media, and frequently green plants were obtained by germination of the embryoids on the induction medium, whereas formation of calli was greatly reduced.Ficoll was tested as a carrier agent in liquid barley anther culture. It gave a higher total yield ofembryoids resulting from an increased number of responding anthers and an increased number of developed structures. When anthers were floated on a Ficoll medium surface the microspores developed inside the anther. After several mitotic divisions the anther wall burst and the proembryoids were expelled onto the surface of the medium. Here their development continued by germination. The substitution of ammonium nitrate by glutamine or asparagine in the liquid medium containing Ficoll was found to be beneficial for culture development.This report is based on the regeneration of 6,827 green plants, with an optimal average ratio of green to albino plants of 1.8. A frequency of 4.6 green plants per plated anther was obtained.

Improvements in the production of doubled haploids in durum wheat (Triticum turgidum L.) through isolated microspore culture

“…Olsen (1987) demonstrated that in barley glutamine can play a key role to increase the proportion of green plants. We have demonstrated that the C 17 medium is a good medium for microspore culture of durum wheat (Cistué et al 2006).…”

“…The importance of an adequate proportion of glutamine in the induction medium for the regeneration of green plants was clearly shown by Olsen (1987) in the case of barley anther culture. In this species, the initial divisions of microspores, further proliferation, embryo formation and plant recovery could be manipulated independently by altering the nitrogen composition of culture media (Mordhorst and Lörz 1993;Mordhorst et al 1997).…”

Genotypic differences in proembryoid development and green plantlets regeneration through androgenesis in barley varieties

“…In barley, as well as other responsive species, inherited factors have been reported as involved in successful haploid plant development (FAROUGHI-WEHR et al, 1982;LARSEN et al, 1991;HENRY et al, 1994). But androgenetic response is possible only when androgenetic genotypes have appropriate environmental conditions that include physiological state of the donor plant, culturing anthers at the right stage of development of microspore and the right culture medium composition (OLSEN, 1987;MORAES-FERNANDES, 1990 (FAROUGHI-WEHR & FRIEDT, 1984;QUÉDRAOGO et al, 1998;MORAES-FERNANDES et al, 1999;SMYKAL, 2000). The purpose of this research was the analysis of in vitro proembryoid development and green plantlets regeneration, in in vitro cultivated anthers, in order to investigate the androgenetic capacity of barley cultivars belonging to crossing block of Embrapa Trigo Barley Breeding Program that had good agronomic traits.…”

Ontogenetic events in androgenesis of Brazilian barley genotypes

“…During the last twenty years improvements in the composition of culture media caused a change in the pattern of differentiation. Instead of disorganized calluses, there was an induction of embryos, increasing substantially the efficiency of plantlet regeneration (Olsen, 1987;Hunter, 1987;Sorvari & Schieder, 1987;Finnie et al, 1989;Daniel & Baumann, 1990;Last & Bretell, 1990;Orshinsky et al, 1990;Kao et al, 1991;Cai et al, 1992;Scott & Lyne, 1994a, b). When compared with organogenesis, regeneration via direct embryogenesis has many advantages.…”