In vitro high frequency plant regeneration from hypocotyl and root segments of spinach by organogenesis

Abstract

An efficient protocol for spinach (Spinacia oleracea L.) plant regeneration from hypocotyl and root segments was established. When the sub-apical hypocotyl and tip-free root segments were cultured on Murashige & Skoog (1962)-based medium containing high concentrations of indole-3-acetic acid (85.62/zM) and gibberellic acid (100 #M), more than 75% and 90% of the hypocotyl and root explants, respectively, formed shoots. After elongation, more than 92% of the shoots rooted on medium supplemented with 2.85-5.71/~M of indole-3-acetic acid. More than 70% of rooted plantlets survived in soil and were fertile. Significant interactions between growth regulator combinations, explant types and environmental conditions on shoot initiation, development and rooting were discussed.

The combined effect of photoperiod, light intensity and GA3 on adventitious shoot regeneration from cotyledons of spinach (Spinacia oleracea L.)

“…Very high levels of GA 3 were used in previous spinach regeneration protocols (Xiao and Branchard 1995), but in our present study, clusters of slender shoots were rarely observed or only calluses were observed at the highest GA 3 concentration tested (2.5 mg l Ϫ1 ). GA 3 is known to promote shoot primordium development (Molvig and Rose 1994), but its effect depends on the cultivar (Al-Khayri et al 1991;Komai et al 1996a;Goto et al 1998;Ishizaki et al 2001), the type of explant (Komai et al 1996a), the effective concentration (AlKhayri et al 1992), the composition and the sequence of plant hormones in the medium (Molvig and Rose 1994) and the photoperiod and light intensity, as shown in our present results.…”

“…Leaf discs, hypocotyls, root segments, leaf-derived protoplasts, thin cell layers from hypocotyls and roots have also been utilized in organogenesis (Al-Khayri et al 1991Goto et al 1998;Knoll et al 1997;Leguillon et al 2003;Mii et al 1992;Molvig and Rose 1994;Sasaki 1989;Xiao and Branchard 1995;Zhang and Zeevaart 1999). Organogenesis has been utilized for the genetic transformation of spinach by Agrobacterium tumefaciens (Al-Khayri 1995;Knoll et al 1997;Zhang and Zeevaart 1999).…”

Efficient in vitro regeneration of fireweed, a medicinal plant

“…In our study, when leaf, petiole and root explants were compared, it was clear that root explants were much more productive for shoot formation than leaf and petiole explants (Table 1). Similarly, root explant was also reported as the most responsive explant in terms of shoot organogenesis with Spinacia oleracea L. (Xiao and Branchard 1995), Hypericum perforatum L. (Zobayed and Saxena 2003), Passiflora cincinnata Mast. (Lombardi et al 2007) and Clitoria ternatea L. (Shahzad et al 2007).…”

In vitro adventitious shoot regeneration of the medicinal plant meadowsweet (Filipendula ulmaria (L.) Maxim)

“…In our study, when leaf, petiole, and root explants were compared, root explants were approximately three times more effective in shoot formation with all PGR combinations and concentrations tested (Tables 1, 2 and 3). Similarly, root explants were reported as the most responsive explant in terms of shoot organogenesis with Spinacia oleracea L., (Xiao and Branchard 1995), Hypericum perforatum L. (Zobayed and Saxena 2003), Passiflora cincinnata Mast. (Lombardi et al 2007), and Clitoria ternatea L. (Shahzad et al 2007).…”