%0 Journal Article %T In vitro Regeneration by Indirect Organogenesis of Selected Kenyan Maize Genotypes using Shoot Apices %A J. Muoma %A G. Muluvi %A J. Machuka %J Biotechnology %D 2008 %I Asian Network for Scientific Information %X The study reports a reliable and reproducible regeneration system of two open pollinated varieties-OPV`s (Katumani KAT and dry land cultivar DLC1), a hybrid (DH01) and an inbred line (TL08) using shoot apices as explants via organogenesis. The shoot apices were cultured on Murashige and Skoog (MS) basal media supplemented with 9 ¦ÌM 2,4-dichlorophenoxyacetic acid (2,4-D) and 8.88, 17.75, 26.64, 35.52 or 44.40 ¦ÌM N6-benzylaminopurine (BAP) with (+) or without (-) 296 ¦ÌM adenine for calli induction. The most effective combination for calli induction was modified MS media containing 26.64 ¦ÌM BAP and 296 ¦ÌM adenine. Calli was maintained on MS media with 9 ¦ÌM 2, 4-D and 4.44 ¦ÌM BAP for calli proliferation. Calli of TL08 genotype directly formed shoots on the media containing 9 ¦ÌM 2, 4-D and 26.64 ¦ÌM BAP, while the KAT, DLC1 and DHO1 formed a mixture of embryogenic and organogenic calli on the media supplemented with 9 ¦ÌM 2, 4-D and 4.44 ¦ÌM BAP. The frequency of callus formation was genotype dependant with KAT 55%, DLC1 35%, DH01 47% and TL08 44%. The number of shoot formed by the selected varieties ranged from 4.9 to 5.7 shoots depending on the genotypes. The number of shoots formed on the media supplemented with 296 ¦ÌM adenine was higher than that on media without adenine. Shoots were regenerated from organogenic calli after 4-6 weeks depending on the genotype and the presence or absence of adenine, with plant regeneration varying from between 29-55%. Root induction was promoted using MS media supplemented with 1.97 and 2.95 ¦ÌM Indole-3-butyric acid (IBA). Seeds from in vitro regenerated plants (R0) produced normal plant (R1) in the field trial and were comparable to the plants grown with the mother seeds. %K Adenine %K in vitro regeneration %K organogenesis %K shoot apices %K Zea mays %U http://docsdrive.com/pdfs/ansinet/biotech/2008/732-738.pdf