Direct in vitro regeneration of castor bean plants (Ricinus communis) using epicotyls

Abstract

DIRECT in vitro REGENERATION OF CASTOR BEAN PLANTS (Ricinus communis) USING EPICOTYLS REGENERAÇÃO DIRETA in-vitro DE PLANTAS DE MAMONA (Ricinus communis) USANDO EPICÓTILOSABSTRACT: A regeneration protocol for castor bean plant (Ricinus communis) was successfully developed using epicotyl sections obtained from in vitro seedlings. The maximum number of induced shoots (4.3 shoots/explant) and highest shoots frequency (75,56%) was obtained in WPM medium supplemented with TDZ (1 mg/L) and zeatin (0.5 mg/L), whereas the minimum number (0.8 shoots/explant) and lowest shoots frequency (37,78%) was obtained in medium containing TDZ (1 mg/L) and BAP (0.5 mg/L). The highest percentage of rooting (93.3%) was obtained in a medium containing IBA (1 mg/L). These plants were transplanted in a mesh house and achieved a high adaptability to acclimatization, reaching 77% survival. On the other hand, the maximum elongation (height) during this stage was 7.9 cm in plants supplemented with WPM nutrients, whereas it was only 4.38 cm in control plants.

An Optimized Protocol for In Vitro Indirect Shoot Organogenesis of Impala Bronzovaya and Zanzibar Green Ricinus communis L. Varieties

“…Gil-Correal et al achieved a 75.56% frequency of regeneration and 4.3 shoots per explant by culturing epicotyls of the "VERC-02" genotype on a medium containing 1 mg/L of TDZ + 0.5 mg/L of zeatin. On the other hand, the 1 mg/L of TDZ + 0.5 mg/L of 6-BAP combination resulted in a large decrease in the regeneration frequency (37.78%) and number of shoots per explant (0.8) [48]. Studying a castor bean genotype from the Rajshahi University Botanical Garden, Alam et al found an 85% regeneration frequency for a culture medium with 3 mg/L of 6-BAP and 36% by using 4 mg/L of 6-BAP + 0.5 mg/L of NAA [45].…”

“…The start of callus formation was observed at days 5-7, which corroborates the results of some other authors. Gill-Correal et al observed the emergence of a callus in the epicotyls of the "VERC-02" castor bean genotype on day 8 [48]. Rahman and Bari described a callus starting in the hypocotyls of cv.…”

“…For example. Alam [45,48,53,54]. Using only 2.4D, Khafagi noted a more intensive growth of the callus compared to the culture media with cytokinins + auxins [53].…”

“…A large number of works were devoted to the in vitro regeneration of castor bean shoots. Protocols with different combinations and concentrations of the PGR (such as BAP, IAA, kinetin, TDZ, and zeatin) have been presented [44][45][46][47][48]. The best results of these experiments are summed up in Table S1.…”

Efficient direct shoot organogenesis and genetic stability in micropropagated sacha inchi (Plukenetia volubilis L.)

“…Several scientific reports have focused on regeneration from hypocotyls and epicotyls in the Euphorbiaceae family [ 5 , 6 ], despite high recalcitrance. Regarding sacha inchi specifically, a few studies have reported the use of in vitro propagation to evaluate the auxin:cytokinin ratio in apical meristems [ 7 ] and different segments of the epicotyl and hypocotyl [ 8 – 10 ], with highest shooting but low process efficiency with 0.5 and 1 mg/L 6-benzylaminopurine and 0.1 mg/L and 0.25 mg/L 1-naphthylacetic acid (NAA).…”