App. Sci. Report. 12 (3), 2015: 128-133 © PSCI Publications Applied Science Reports www.pscipub.com/ASR E-ISSN: 2310-9440 / P-ISSN: 2311-0139 DOI: 10.15192/PSCP.ASR.2015.12.3.128133 Combined effect of hormonal concentrations (naa and bap) on root formation kenaf ( hibiscus cannabinus l.) R. Sultana 1 , A.K.M.L.Quader 2 , Maksudul Haque 3,* , S.Mazumder 4 , S.K.Paul 5 1. Biotechnology department, Bangladesh Agricultural University, Mymensingh, Bangladesh, 2. Agronomy department, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh, 3. Scientific officer, Plant Breeding Division, Bangladesh Rice Research Institute, Gazipur 1701, Bangladesh 4. Sher-e-Bangla Nagar Adorsha Mohila College, Dhaka-1207, Bangladesh, 5. Scientific Officer, Agronomy Division, Bangladesh Agricultural Research Institute, Joydebpur, Gazipur-1701, Bangladesh. *Corresponding author email: maksudulhq@gmail.com Paper Information A B S T R A C T Received: 14 June, 2015 Accepted: 29 September, 2015 Published: 20, December, 2015 Citation Sultana R, A.K.M.L.Quader AKML, Maksudul Haque MH Mazumder S, Paul SK. 2015. Combined effect of hormonal concentrations (naa and bap) on root formation kenaf (hibiscus cannabinus l.). Applied Science Reports, 12 (3), 128-133. Retrieved from www.pscipub.com (DOI:10.15192/PSCP.ASR.2015.12.3.128133) The present study was undertaken to investigate the comparative regeneration potential of seedling explants of kenaf (Hibiscus cannabinus L.) at the Biotechnology Laboratory, Department of Biotechnology, Bangladesh Agricultural University, Mymensingh, during the period from January, 2014 to June, 2014. An efficient regeneration protocol was developed for kenaf genotypes HC-2, HC-95 and HC-3 using root tip, cotyledon and hypocotyl as explants. For regeneration, Murashige and Skoog (MS) medium was used as culture medium and supplemented with different concentrations and combinations of NAA (α-napthaleneacetic acid) and BAP (6-Benzylaminopurine) as growth regulators. Different concentrations and combinations of hormones for root formation NAA (0.0, 1.0, 1.0, 1.5, 2.0, 2.0 and 2.0 mg/L) and BAP (0.0, 1.0, 2.5, 5.0, 7.5, 10.0 and 15.0 mg/L) were used. The HC-2 genotype had the highest root formation (40.86%) and HC-95 genotype had the lowest value 26.11% for root formation respectively. The root formation (49.67%) occurred the best on 2.0 mg/L NAA + 7.5 mg/L BAP combination. On the other hand, hypocotyl explant showed the highest root formation (55.72%) followed by the other two explants (Root tip and cotyledon) which had root formation (0.0%, 50.38%). The explant from the hypocotyl of genotype HC-2 showed the best performance root formation (88.67%) in 2.0 mg/L NAA +7.5 mg/L BAP combination within 7-10 days compared with genotype HC-95 and HC-3. The frequency of variation was found to be genotype dependent. Certain changes were found in regeneration of all the three genotypes, suggesting the existence of a mutation-sensitive part of the kenaf genome and possibility of improvement through somaclonal variation. © 2015 PSCI Publisher All rights reserved. Key words: Hormonal concentrations, Root formation, Explants, Kenaf (Hibiscus cannabinus L.) Introduction Kenaf (Hibiscus cannabinusL.) is a short-day, fast grwing annual, herbaceous plant cultivated for its stem fiber. It is native to tropical regions of Asia and Africa. It belongs to the Malvaceae family. Kenaf is closely related to cotton, roselle and hollyhocks. The kenaf plant has a wider range of adaptation to climate than any other fiber plant grown for commercial use. It can grow well and produce high fiber yield on an enormously wide range of soils. It has been widely planted due to its multiple uses ranging from basic animal feed to a variety of bio-composite products focuses on fibre production, such as making ropes, sacks, canvases and carpets (Li, 1980). Advanced biotechnology provides both an innovation method for kenaf breeding and germplasm multiplication and accelerates the process of kenaf breeding. The plant breeding methods can be combined with tissue culture methods in order to form genetic variability for desired traits (Nazet al., 2007; Ozyigit&Gozukirmizi, 2008). The application of biotechnology in combination with the traditional breeding methods will cause the gigantic task of increasing food production. The development of insect and/or disease-resistant transgenic kenafs would greatly enhance conventional breeding efforts. Mclean et al. (1992) reported organogenesis of kenaf via callus culture but failed or were irreproducible. Banks et al. (1993) demonstrated foreign gene expression in kenafcallus, however, they were not able to regenerate plants.