International Research Journal of plant and Crop Sciences ISSN: 1711-3490 Vol. 1(1), pp. 005-014, November, 2013. © Advanced Scholars Journals

Full Length Research Paper

Development of a highly efficient in vitro Culture system for Ugandan adapted sorghum Genotypes

Muhumuza, J .B^{1, 2} and Okori P¹

¹ School of Agricultural Sciences, Makerere University, P.O. Box 7062,Kampala Uganda.

² Mbarara Zonal Agricultural Research and Development Institute,P.O Box 389, Mbarara Uganda.

*Corresponding author. E-mail: [email protected] 

Accepted 22 October, 2013

Abstract

World over sorghum genetic transformation is limited by its recalcitrance to tissue culture and genotype dependent regeneration and Ugandan adapted sorghum genotypes may not be exceptional. This study intended to develop an efficient in vitro culture system for Ugandan adapted sorghum genotypes and identify genotypes amenable to in vitro culture under different test conditions. Ages of IZE and phytohormone callus induction medium composition were optimized. Twenty Ugandan adapted sorghum genotypes were screened on two medium types; Murashige and Skoog and L3 basal medium. Optimum in vitro culture responses were achieved at 2, 4-D level of 2.5 mg/l supplemented with 0.5 mg/l of kinetin hormone. Inclusion of kinetin hormone in callus induction medium at low 2, 4-D levels gradually reduced the callus induction frequency while higher 2, 4-D levels exhibited inhibitory effects. The best age of IZE for in vitro culture was between 16-18 days post anthesis. IZE physiological state of different genotypes at the same age varied. Strong genotype by medium type influenced in vitro culture responses rather than the genetic control only. MUC007/194 and MUC007/193 have been earmarked as model genotypes for in vitro culture and can be systems to introgress useful genes into recalcitrant but commercially viable genotypes.