Abstract

Influence of ten different genotypes, age of trees and environmental temperature on induction of androgenesis and apperance albino horse chestnut embryos were studied. Efficiency of in vitro androgenesis via anther and microspore culture had been investigated. Microspores and anthers were used from the same closed flower bud. Androgenic response of different genotypes was measured and compared. Anther induction rates were from 5 to 37.6%, depending on genotype. The number of embryos per isolated anther varied between 0.5 to 5.0 embryos in anther culture, while in microspore culture varied between 3.0 to 27 embryos, depending on genotype. A microspore culture was 5 - 6 times efficient than anther culture for same genotype. Age of the trees had no influence on androgenesis induction. Temperature of about 4 - 5^°C was optimal for androgenic embryo induction. Albino horse chestnut embryos phenomenon depended on genotype. The number of albino appearing in anther was higher than in microspore culture. The same correlation of appearing albino was observed between short and long day.Flow cytogenetic analysis of androgenic embryos originating from anther and microspore culture was done after a first generation of regenerants. All androgenic embryos, the first generation from microspore culture were haploid, while 50% of the regenerants originating from anther culture were haploid, and the other half diploid.

Key words: Horse chestnut, genotype, environmental impact, androgenic embryos,ploidy stability.