Assessment of phenotypic and genetic stability in strawberry plants cv. Festival derived from different in vitro propagation methods using SSR and ISSR markers

Abstract

Different propagation methods using two explants types, subculture number and growth regulators type and concentration were studied to examine their effects on organogenic potential, phenotypic and genetic stability in strawberry cv. Festival. Our results proved that the significant highest shoot number was achieved after 7th subculture of meristem tip on MS medium containing 0.5 mg/l BA and direct regeneration of shoots from leaf disc explants on TDZ containing medium. However, the significant lowest shoot number was obtained after 12th subculture of meristem tip using 2 mg/l BA. Shoot number produced through an indirect regeneration method using 2,4-D+BA significantly decreased in comparison to the direct regeneration method using TDZ-containing medium. Ex vitro phenotypic test showed that leaf morphology, serration pattern and stomata number were similar among plants obtained from different propagation methods comparing with mother plants. In the same direction, SSR analysis indicated that plantlets of cv. Festival obtained from meristem-propagation method subculture up to 12th generation using high BA concentration (2.0 mg/l) were genetically stable (zero% polymorphism) as compared with control plantlets and ex vitro mother plants. Also, direct regenerated and callus derived plantlets were also genetically stable using SSR markers. However genetic differences were detected using ISSR technique (32% polymorphism), where plantlets from 12th subculture using high BA (2.0 mg/l) and callus derived plantlets were genetically differed from each other and from control plantlets, mother plants as well as plantlets derived from 7th subculture using 0.5 mg/l BA. Micropropagated shoots from meristem culture up to 7th subculture and regenerated ones from leaf disc using
TDZ may be produce genetically stable plantlets in the commercial production nurslings of cv. "Festival".