SHORT COMMUNICATION In vitro shoot growth, direct organogenesis and somatic embryogenesis promoted by silver nitrate in Coffea dewevrei Vaddadi Sridevi & Parvatam Giridhar Received: 6 November 2011 / Accepted: 13 June 2012 / Published online: 9 January 2013 # Society for Plant Biochemistry and Biotechnology 2013 Abstract Direct differentiation of shoot buds in Coffea dewevrei was evident from the seedling shoots with collar region and also from collar region end of hypocotyl seg- ments in presence of 40 μM AgNO 3 , 8.88 μM of BA and 2.85 μM of IAA. Apart from this, shoot end of hypocotyl explants mainly supported yellow friable callus or somatic embryos. Subsequent transfer to the same medium induced secondary somatic embryogenesis. The collar region of the hypocotyl explants not only showed direct organogenesis by producing 1–3 shoots per explant and also able to produce globular somatic embryos and embryogenic yellow friable callus. Similarly direct somatic embryogenesis along with yellow friable embryogenic callus formation on 1/2 strength MS medium comprising 1.47 μM IAA, 2.22 μM BA and 40 μM AgNO 3 was noticed from cut portion of in vitro leaf and stalk of regenerated plants. The microshoots rooted well upon subculturing onto the same medium in 6 weeks and showed 60 % survival in green house and resumed growth upon hardening. Keywords Collar region . Coffea dewevrei . Organogenesis . Silver nitrate . Somatic embryos Abbreviations AgNO 3 Silver nitrate BA Benzyladenine IAA Indole-3-acetic acid MS Murashige and Skoog RH Relative humidity Introduction The genus Coffea (Rubiaceae) includes more than 60 spe- cies, out of this Coffea arabica and C. canephora are prominent in the trade of coffee beans and the cultivation of the other two minor species C. liberica and C. dewevrei is limited. C. dewevrei (2n=22) belongs to section Eucoffea and subsection Pachycoffea (Carvalho and Monaco 1967). C. dewevrei is highly resistant to rust infections with good yield and also require temperature and good light for culti- vation (Chevalier 1947; Lopes and Monaco 1979). The levels of caffeine in C. dewevrei is ~1.2 % (Ashihara and Crozier 2001) which is more than that of C. arabica (1.0 %) but less than that of C. canephora cv. Robusta (1.7–2.0 %). Earlier studies showed that in matured fruits of C. dewevrei the alkaloid caffeine metabolizes rapidly when compared to the other species (Mazzafera et al. 1991; Mazzafera 1993). When grown undisturbed C. dewevrei attain a greater height compared to that of C. canephora and C. arabica and it may require 4–5 years to bear fruiting. Moreover, it finds use in C. canephora breeding programmes. Though in vitro prop- agation and somatic embryogenesis protocols are well estab- lished for both C. arabica and C. canephora varieties (Giridhar et al. 2004; Vinod et al. 2006a) including the genetic transformation methods for caffeine regulation (Vinod et al. 2006b) no such reports are available with C. dewevrei. While pursuing the metabolic engineering of caf- feine in Coffea, C. dewevrei could be used as a model for desired gene silencing. As a tool for such studies somatic embryos are highly useful for efficient gene transfer through Agrobacterium mediated transformation. Apart from this, in vitro propagation methods for C. dewerei could be suitable for mass multiplication for its commercial cultivation in view of its superior features such as clustered fruit V. Sridevi : P. Giridhar (*) Plant Cell Biotechnology Department, CSIR-Central Food Technological Research Institute, Mysore 570 020, India e-mail: parvatamg@yahoo.com J. Plant Biochem. Biotechnol. (January–March 2014) 23(1):112–118 DOI 10.1007/s13562-012-0186-2