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Maize is a staple food crop for millions of Africans. Despite this fact, African farmers have been harvesting average grain yield of not more than 2 t/ha while there is a potential of producing more than 10 t/ha. Drought is one of the major abiotic constraints contributing to this low productivity. Drought diminishes crop productivity mainly by causing premature leaf senescence. The ipt gene codes for isopentenyltransferase (IPT) enzyme which catalyzes the rate limiting step in the biosynthesis of cytokinin and has been shown to enhance tolerance to drought in transgenic crops by delaying drought-induced leaf senescence. This created interest to investigate if ipt gene can be useful in enhancing drought tolerance in locally adapted African tropical maize genotypes. The tropical maize inbred line CML216 was transformed with ipt gene using Agrobacterium-mediated transformation method. Five transgenic lines which were proved to be stably transformed through Southern blot analysis with copy number of 2 to 4 per event were developed. In drought assay carried out in the glass house, transgenic lines expressing the ipt gene showed tolerance to drought as revealed by delayed leaf senescence compared to the wild type plants. Transgenic plants maintained higher relative water content and total chlorophyll during the drought period and produced significantly higher mean grain yield of 44.3 g/plant while the wild type plants produced mean grain yield of 1.43 g/plant. It is proposed that the transgenic lines developed in this study can be further tested for tolerance to drought under contained field trials. Furthermore, transgenic lines developed can be used in breeding programs to improve drought tolerance in other commercial tropical maize genotypes through conventional breeding. Key words: Cytokinin, delayed leaf senescence, drought inducible, CML216, ipt gene.

The Cartagena Protocol on Biosafety to the Convention on Biological Diversity is an internationally binding instrument addressing issues of biosafety. Biosafety refers to the need to protect human health and the environment from the possible adverse effects of the products of modern biotechnology. Accordingly, all countries to the convention are required to put in place regulatory mechanisms to enhance the safety of biotechnology in the context of the Convention’s overall goal of reducing all potential threats to biological diversity, while taking into account the risks to human health. Therefore, each country party to the convention has its own procedures to enact laws to guide the safe use of biotechnology. In Uganda, the process involves the drafting of the bill by the first parliamentary counsel, approval by cabinet, first reading at the parliament, committal to the responsible parliamentary sessional committee, tabling of the bill for public hearing, consultations, and final approval. In Uganda, the Committee on Science and Technology is responsible for the Biosafety Bill. In March 2013, the Committee tabled the bill for public hearing and submissions from public institutions. There were comments supporting the passage of the Bill and comments in objection. The reasons for objection are mainly due to precaution, speculation, lack of knowledge about biotechnology and biosafety, and alleged influence from biosafety entrepreneurs. This article reviews these public views, revealing controversy and possible consensus to pass the bill.

Striga hermonthica (Del.) Benth. is the major biotic constraint to sorghum production. Its control is difficult and can only be achieved through integrated management strategies that depend mainly on host plant resistance and enhanced soil fertility. However, breeding for resistance is hampered by the complexity of host parasite interactions and lack of reliable screening methods. The invention of molecular markers has enhanced the effectiveness of breeding for resistance. Five genomic regions (QTLs) with linked markers associated with Striga resistance were mapped in sorghum variety N13 by [10]. In this study, to increase the efficiency of marker-assisted selection (MAS), 27 EST-SSR markers in close association with Striga resistance QTLs were also identified and mapped. Populations of backcross (BC 3 S 4 ) derived from N13 (Striga resistant) X three farmer preferred sorghum cultivars: Tabat, Wad Ahmed and AG-8 (Striga susceptible) were generated. Thirty-one lines (BC 3 S 4 ) with confirmed Striga field resistance were genotyped with foreground and background selection makers. Twenty resistant lines, with two or more major QTLs were selected for regional evaluation. Of these 10 lines were selected and advanced for multi-location testing, together with Wad Ahmed, Tabat, AG-8, N13, SRN39 and IS9830 as checks. Standard variety trials were conducted in Striga sick plots over three seasons (2009-2011) in Sudan, Gezira Research Station, Damazine, Sinnar, and Gedarif. Results revealed that four lines (T1BC 3 S 4 , AG6BC 3 S 4 , AG2BC 3 S 4 and W2BC 3 S 4 ) were Striga resistant and agronomically superior with yields ranging from 180% to 298% higher relative to their recurrent parents. This Striga resistance coupled with superior attributes of the recurrent parent (including very high yield potentials, high grain quality and drought tolerance) will provide adaptation and stability across a wide range of environments. These are the first products of DNA markerassisted selection (MAS) in sorghum released for cultivation by farmers in sub-Saharan Africa.