High frequency of plant regeneration from anther culture in flax, Linum usitatissimum L.

Abstract

The effects of induction medium compositions on flax anther culture were investigated in order to improve the efficiency of callus induction and plant regeneration. Anthers were inoculated onto the modified MS medium supplemented with five different combinations of plant growth regulators. The medium containing the combination of 2mg/l 2,4-dichlorophenoxy-acetic acid (2,4-D) and 1 mg/1 6-benzylaminopurine (BAP) produced a significantly higher number of calli forming shoots/100 responded anthers and a significant increase in overall efficiency of regeneration than the same basal medium containing 1 mg/1 a-naphthalene-acetic acid (NAA) and 2 mg/1 BAP (CK). Among the five levels of thiamin hydrochloride tested, the modified MS medium containing 10 mg/1 thiamin hydrochloride significantly increased the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration compared with the same basal medium containing 0.1 mg/1 thiamin hydrochloride. Maltose concentration had a significant effect on the percentage of anthers producing calU, the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration. The medium containing 6% or 9% maltose produced the highest overall efficiency of regeneration among the five levels of maltose evaluated. Sucrose concentration significantly affected the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration, and dramatically affected the frequency of microspore-derived plants and the frequency of spontaneous chromosome doubhng in microspore-derived plants. The efficiency of doubled haploid line production obtained in this study appears adequate for applied breeding programmes.

Effect of genotype and medium composition on flax Linum usitatissimum L. anther culture

“…However, comparison based on anther efficiency was more accurate than the overall efficiency of regeneration as shoot regeneration from possibly fragmented callus did not affect anther culture efficiency. Previous study demonstrated that A 22 C-9 had a lower overall efficiency of regeneration and a higher percentage of microspore-derived plants than A 22 C medium containing 6% sucrose (A 22 C-6) for flax AC McDuff/AC Emerson F 1 hybrid (Chen et al 1998b). As a result, the overall efficiency of doubled haploid plants production was shown to be similar between A 22 C-9 and A 22 C-6.…”

“…The anther culture procedure was the same as described previously (Chen et al 1998b). Essentially, five anthers from each of two buds (total ten anthers) with microspores at the mid to late uni-nucleate stage were inoculated onto a plastic petri dish (35×10 mm) containing 3 ml callus induction medium solidified with 0.4% Sea Plaque agarose.…”

“…The overall efficiency of regeneration through anther/microspore culture has been too low to be used for practical applications (Sun and Fu 1981;Nichterlein et al 1991;Nichterlein and Friedt 1993). Recently, the overall efficiency of regeneration in flax anther culture has been improved dramatically through the modification of anther culture conditions (Chen et al 1998a) and medium composition (Chen et al 1998b). The microsporederived populations and doubled haploid populations have been used to study the inheritance patterns of molecular markers and disease-resistance genes (Chen et al 2001).…”

Effect of genotype and medium composition on linseed (Linum usitatissimum) ovary culture

“…Cultivars 'Linola', 'Mikael' and 'Szaphir' showed the highest shoot regeneration frequency when callus had originated on induction medium supplemented with 2 mg L −1 BAP and 1 mg L −1 NAA while combination of 1 mg L −1 BAP + 2 mg L −1 IAA promoted shoot formation in ovaryderived callus of 'Barbara'. In Linum usitatissimum it was reported that the combination of 1 mg L −1 BAP with 2 mg L −1 2,4-D in the induction medium dramatically improved organogenetic capacity of anther culture-derived callus in subsequently significantly increased the overall efficiency of regeneration compared with the combination of 2 mg L −1 BAP and 1 mg L −1 NAA (Chen et al 1998). In the present study, the combination of 1 mg L −1 BAP and 2 mg L −1 2,4-D in the induction medium significantly decreased shoot regeneration frequency in 'Barbara', 'Mikael' and 'Szaphir', and completely inhibited shoot formation from ovaryderived callus of 'Linola'.…”

“…It is a dual-purpose crop, a source of oil and fibre. Breeding of linseed, which is practiced in many countries of the world, even nowadays is a long and complicated process, based on interspecific hybridization and selection of the best plants, therefore the development of genetically stable lines takes a very long time -10-12 years (Chen et al 1998). Rapid breeding techniques could help in producing new linseed lines such as those resistant to pathogen infection and/or with increased productivity (Rutkowska-Krause et al 2003).…”