Response of flax genotypes to doubled haploid production

Forty-four flax genotypes with a diverse genetic background were evaluated for anther culture response using a standard anther culture protocol in order to determine the feasibility to initiate a routine haploid production system in applied breeding programs. A strong genotype effect on callus induction and shoot regeneration in anther culture was found in this study. A number of genotypes, including two low cadmium content lines 96-11785 and 96-11826, a high oil content line 96-22109 and a high linolenic acid content line M 4919 were identified as highly responsive. The impact of the findings in this study on flax breeding was discussed. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effect of sucrose concentration on elongation of shoots from flax anther culture

Anther culture is considered as the most successful method of producing doubled haploid plants in flax. The efficiency of shoot regeneration from anther culture has been improved dramatically by optimizing culture temperature and callus induction medium. However, shoot elongation has become increasingly the limiting factor for further improvement of the overall efficiency of doubled haploid production. The effect of sucrose con- 21 centration on shoot elongation was investigated in this study. The medium containing 10 g l sucrose produced longer and more vigorous shoots than the same medium containing other concentrations of sucrose. The possible physiological basis of sucrose on shoot elongation in flax was discussed.     

Identification of microspore-derived plants in anther culture of flax (Linum usitatissimum L.) using molecular markers

The microspore origin of anther-culture-derived plants of flax was determined using inter-simple sequence repeat (ISSR) and randomly amplified polymorphic DNA (RAPD) markers. Polymorphic fragments between the two parents of the F₁ donor plants were identified and their segregation patterns in anther-culture-derived plants were used to elucidate the origin of those plants and to determine the degree of independence of plants regenerated from the same callus. Using one ISSR primer (UBC 889) and two RAPD primers (UBC 556 and 561), 12 out of 16 plants were unequivocally identified as being derived from microspores. Plants derived from the same callus had identical PCR patterns at five polymorphic loci and thus were likely derived from the same microspore. Therefore, it is proposed that the number of calli forming shoots be used to describe the anther culture efficiency in flax. Received: 3 February 1998 / Revision received: 8 June 1998 / Accepted: 8 July 1998