Precocious <i>In-Vitro</i> Flowering of Perennial Asparagus (<i>Asparagus officinalis</i> L.) Regenerants with a Chemical Inducer

Abstract

A precocious flowering system of regenerants in asparagus ( Asparagus officinalis ) was achieved by treatment with a chemical inducer. Somatic embryos withered completely by being processed for 8 - 12 days with 200 μM n -propyl N -(3,4-dichloro - phenyl)carbamate that had been dissolved in distilled water. In contrast, precocious flowering occurred at an extremely low rate (3.4%) when somatic embryos were processed in carbamate dissolved in Murashige and Skoog’s liquid medium. To encapsulate the female and male embryos, we surveyed the optimum conditions of viscosity and concentration of sodium alginate for encapsulating the seeds, and we screened the values of 80 - 120 cps and 2% - 3%, respectively. The synthetic seeds produced also withered when they were processed with the carbamate dissolved in distilled water. However, when Murashige and Skoog’s liquid medium was used for the solvent, the flowering frequency of the synthetic seeds was enhanced (13.3%). Based on our morphological and histological observations, female and male regenerants that were processed with the carbamate solution produced individual flower organs. The conversion of sex expression did not occur. A precocious flowering system would allow a significant reduction in the time required for perennial seedlings to flower and can, therefore, save time required for further experiments that employ floral homeotic mutants.