Factors effecting adventitious shoot regeneration from leaf explants of quince (Cydonia oblonga)

Abstract

A procedure for adventitious shoot regeneration from leaf explants of quince (Cydonia oblonga Mill.) using thidiazuron (TDZ) was developed. Excised leaves of cultures grown on Murashige and Skoog (MS) medium containing 5 p~M benzyladenine (BA) and 0.9% Gibco Phytagar were used. Several experiments were conducted to determine optimum concentrations of thidiazuron, a-naphthaleneacetic acid (NAA) and sucrose. When the medium contained 1.5 txM TDZ and 2.5 ~M NAA, 85% of the discs regenerated shoots with an average of eight shoots per leaf disc. An incubation period of three weeks in the dark was necessary for optimum shoot regeneration. Leaves excised from four to six-week-old cultures gave a higher percent shoot regeneration than leaves from cultures older than six weeks. Regeneration percentages were significantly reduced when sucrose concentration in the medium was less than 3%. A significantly higher percentage of shoots regenerated when leaf discs were placed on the regeneration medium abaxial side down as compared to the adaxial side.Regenerated shoots were cultured on MS medium containing 5 txM BA and rooted on half-strength MS medium containing 10 txM NAA. Rooted plantlets were acclimatized to greenhouse conditions for evaluation of any somaclonal variation. The importance of these findings are discussed in relation to in vitro improvement of plants.

Adventitious bud regeneration from leaf explants of Platanus occidentalis L. and genetic stability assessment

“…In our study, when 40-day-old and other younger or older leaves were compared, it was clear that 40-day-old explants were much more productive for shoot formation than others. Similar studies have also been reported in Prunus (Mante et al 1989), Lachenalia (Niederwieser and Van Staden 1990), Cydonia oblonga (Baker and Bhatia 1993), Aegle marmelos (Islam et al 1993) and Malus (Famiani et al 1994).…”

“…Prior incubation in the dark is very important process for dedifferentiation and differentiation of P. occidentalis. Incubation in the dark has been reported to increase shoot regeneration in various plant species, such as blueberry (Billings et al 1988), pear (Chevreau et al 1989), apple (Fasolo et al 1989), campanula (Sriskandarajah et al 2004), watermelon (Compton 1999), Zhanhua winter jujube (Gu and Zhang 2005) and quince (Baker and Bhatia 1993). Our results indicated that an incubation period of 7 days in the dark is optimal for shoot regeneration of P. occidentalis (data not presented).…”

Plant regeneration: cellular origins and molecular mechanisms

“…Explants from juvenile plants regenerate shoots more effectively than those from mature plants (Dong and Jia, 1991;Baker and Bhatia, 1993;Becerra et al, 2004;Zhang et al, 2015). The decline in shoot regeneration capacity with aging is at least partly due to a reduced responsiveness to plant hormones.…”

Plant regeneration and morphology during in-vitro organogenesis fromHeloniopsis orientalis (Thunb.) C. Tanaka

“…Our preliminary experiments indicated a difference in response between tissues pretreated in the dark, followed by culture under illumination versus those not receiving the dark pretreatment. Incubation in the dark also increases shoot regeneration in species such as blueberry (Billings et al, 1988), pear (Chevreau et al, 1989), apple (Fasolo et al, 1989), quince (Baker and Bhatia, 1993), and rose (Ibrahim and Debergh, 2001). Therefore, we conclude that incubating the tissue for 10 d in the dark is more effective for promoting shoot regeneration in H. orientalis.…”