Abstract
Callus holds great potential for biotechnology applications in plants. In this study, several experiments were performed to establish a protocol for in vitro induction of good quality callus by using immature cotyledons and embryos of Juglans regia cv. ‘Xiangling’ as the explants. DKW basal media supplemented with different concentrations of plant growth regulators were applied to determine the induction rate, texture and color of the recovered callus. Results showed that the optimum culture medium for the callus induction from these explants was a DKW basal medium consisting of 1 mg/L BA, 2 mg/L KT 250 mg/L glutamine, 500 mg/L casein hydrolysate, 200 mg/L Vc, 50 g/L sucrose and 2.8 g/L Gelrite (i.e., the T8 medium). The average rate of callus induction on the medium reached 80.7% for the immature cotyledons and 66.7% for the immature embryos, and all the callus was characterized by a friable, creamy or yellow appearance. In vitro proliferation of callus was not very successful as a result of the fact that the friable callus with creamy or yellow color grew very slowly, whereas the fast-growing callus was easy to turn brown and died eventually. Even though further investigation will be required to overcome the problem of browning and assess the regeneration ability of the callus, this approach for the production of friable callus may have valuable applications for walnut and other woody trees.
Highlights
The common walnut (Juglans regia), one of the ancestral species of Juglans, is a popular fruit crop with a potential for nut production, as it is abundant in nutritious substances and dietary minerals (Vahdati et al, 2008, 2009)
Most of these researches focused on browning phenomenon, shoot or bud elongation, root induction, embryo germination or somatic embryogenesis (Fernández et al, 2000; Vahdati et al, 2006, 2008, 2009; Amiri, 2006; Fatima et al, 2006; Leal et al, 2007; Avilés et al, 2009; Toosi and Dilmagani, 2010; Payghamzadeh and Kazemitabar, 2010, 2011; Amiri and Gharati, 2012; Gotea et al, 2012)
Callus induction from the immature cotyledons After 3 days of culture, the excised immature cotyledons gradually changed color from white to green on all media, and the initiation of callus was observed around the cut edge of the explants after another one week of culture on all media except medium CK, the control
Summary
The common walnut (Juglans regia), one of the ancestral species of Juglans, is a popular fruit crop with a potential for nut production, as it is abundant in nutritious substances and dietary minerals (Vahdati et al, 2008, 2009). Previous reports suggested that somatic embryogenesis could be induced from immature cotyledons, embryos, embryonic axes and endosperm on an appropriate medium (Tulecke et al, 1988; Tang et al, 2000; Fernández et al, 2000; Vahdati et al, 2006; Fatima et al, 2006; Toosi and Dilmagani, 2010; Payghamzadeh and Kazemitabar, 2011).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
