Cytogenetic variation in somatic tissue cultures and regenerated plants of barley (Hordeum vulgare L.)

Abstract

Chromosome number of morphogenic and non-morphogenic calli and regenerated plants of barley were determined. Cultures were obtained from two kinds of explants, immature embryos and seedling leaves from three cultivars, Ingrid, Dissa and Golden Promise. Callus chromosome analyses were carried out during a 12 month period in a medium containing 2 mg/1 of 2,4-D. Diploid cells were predominant in all cases; although in leaf-derived cultures tetraploid cells (2n --4x --28) showed a tendency to increase as time in culture increased and after more than six months in culture, diploid cells decreased to percentages of almost 70%. Aneuploid cells were generally infrequent in all cases. The source of explant has been more important than the genotype (cultivar) and the type of callus (morphogenic vs. non-morphogenic) in the chromosomal stability of cultures as time increases. From short term cultures, only 1.85% of the regenerated plants were tetraploid, the remaining were diploids. The ability of morphogenic calli to regenerate plants decreased before any significant reduction of diploid cells were observed.

Somaclonal Variation and Induced Mutations in Crop Improvement

“…Gonzalez et al (1996) suggested that the source of explant, the type of callus (morphogenie vs. non-morphogenic) and duration of culture was more important than the genotype in determining chromosomal stability of barley cultures. Gonzalez et al (1996) suggested that the source of explant, the type of callus (morphogenie vs. non-morphogenic) and duration of culture was more important than the genotype in determining chromosomal stability of barley cultures.…”