Micropropagation of wild species of the genus Asparagus L. and their interspecific hybrids with cultivated A. officinalis L., and verification of genetic stability using EST-SSRs

Abstract

An efficient micropropagation method forasparagus species was developed in this study. The methodallows the fast cloning of the elite genotypes from differentasparagus species and the interspecific hybrids obtainedfrom these species. Rhizome bud explants were disinfectedusing 3 g l-1 of benomyl and 20 g l-1 of sodium hypochlorite.Then, they were cultured on Asparagus RhizomeBud Medium 3 (ARBM-3) consisting in modified Murashigeand Skoog medium with salts with EDDHA-Fe(85.7 mg l-1) instead of EDTA-Fe and vitamins, supplementedwith 0.3 mg l-1 NAA, 0.1 mg l-1 KIN, 2 mg l-1ancymidol and 6 % sucrose. Results showed that themethod developed produced high disinfection rates(70?95 %). More than 70 % of the explants developedshoots and the rooting rate on ARBM-3 medium was30?45 %. The rooting rate increased to 60?85 % when theunrooted shoots were subjected to an additional cycle ofrooting, reaching 100 % after two cycles of rooting. Themultiplication was achieved through mechanical divisionof rooted shoot clusters growing in ARBM-3. The acclimatizationrate of the micropropagated plantlets was higherthan 90 %. The micropopagated plantlets were screened forsomaclonal variation using 12 expressed sequence tagderived simple sequence repeat markers. The results confirmedthe character ??true to type?? of the plantlets, indicatingthat the method developed in this study can be usedto successfully micropropagate asparagus species.