Regeneration of soybean (Glycine max L. Merrill) through direct somatic embryogenesis from the immature embryonic shoot tip

Abstract

We describe here a simple and efficient system of soybean (Glycine max L. Merrill) regeneration through direct somatic embryogenesis by using immature embryonic shoot tips (IEST) as explants. The cultivar Kaohsiung 10 (cv. K10) used in this study did not show embryogenic response either from mature seed-derived explants (cotyledon, embryonic tip, leaf, shoot and root) or immature cotyledons. However, it showed a high percentage (55.8%) of somatic embryo (SEm) formation from the IEST excised 2-3 wk after flowering, thus indicating the crucial roles of type and age of explants. The IEST put forth primary SEm after 2 mo of culturing on Murashige and Skoog (MS) medium supplemented with 6% sucrose, 164.8 A mu M 2,4-dichlorophenoxyacetic acid (2,4-D), 5 mM asparagine and 684 A mu M glutamine. Subsequently, secondary SEm were developed 1 mo after culturing on MS medium containing 123.6 A mu M 2,4-D and 3% sucrose. Cotyledonary embryos were induced on MS medium supplemented with 0.5% activated charcoal after 1 mo. The embryos were desiccated for 72-96 h on sterile Petri dishes and regenerated on hormone-free MS medium. Plantlets with well-developed shoots and roots were obtained within 5-6 mo of culturing of IEST. The SEm-derived plants were morphologically normal and fertile. Various parameters thought to be responsible for efficient regeneration of soybean through somatic embryogenesis are discussed. To our knowledge, this is the first report to employ IEST as explants for successful direct somatic embryogenesis in soybean

First Report of Agrobacterium tumefaciens mediated genetic transformation of aquatic Rice paddy herb (Limnophila aromatica)

“…Thereafter, in vitro regenerated shoot tip explants were taken for genetic transformation studies. Shoot tip explants are potent explants used for genetic transformation studies in other economically important plants like corn (Cao et al, 2014;Zhong and Sticklen, 2000), cotton (Gould et al, 1998;Lei et al, 2012), soybean (Loganathan et al, 2010), jute (Saha et al, 2014), eucalyptus (Silva et al, 2011) etc. showing their suitability for genotype independent genetic transformation.…”

Induksi dan Proliferasi Embriogenesis Somatik In Vitro pada Lima Genotipe Kedelai

“…Loganathan et al (2010) menunjukkan bahwa genotipe sangat berpengaruh dalam keberhasilan embriogenesis somatik. Beberapa genotipe lebih responsif terhadap media kultur dibandingkan genotipe lainnya (Thiruvengadam et al, 2006;Hiraga et al, 2007;Yang et al, 2009).…”

Soybean: Plant Manipulation to Agrobacterium Mediated Transformation

“…Such variability's can partially be overcome by some modifications in embryogenesis and regeneration protocols (Bailey et al, 1993). Recently Loganathan et al (2010) reported the somatic embryogenesis from immature embryonic shoot tips on MS medium containing 6% sucrose, 2,4-D and amino acids. The embryos efficiently regenerated into shoots on hormone free MS medium containing charcoal.…”