Quality protein maize (QPM) is a high-lysine, hightryptophan variety. The essential amino acid profile, the protein efficiency ratio (PER) of mixtures of QPM and normal maize, and the hedonic response to three traditional foods were studied with four QPM varieties. The lysine content of the QPM varieties ranged from 3.7 to 4.2 g/100 g protein and was significantly (p < .05) higher than that for normal maize (2.6 to 3.1 g/100 g protein), but lower than the FAO-recommended human level of 5.0 g/100 g protein, The PER values of normal maize showed significant (p < .05) improvement at replacement levels of 60% or more with QPM. The overall acceptability scores showed that QPM varieties were equally acceptable as normal maize in ga kenkey and were preferred to the local normal maize in tuo zafi. The tropical Ghanaian QPM varieties have enhanced amino acid profiles and were acceptable in traditional foods.

The current study aimed at evaluating the effect of gibberellic acid (GA 3 ) and sucrose on in vitro propagation of two elite sweet potato cultivars (Ukerewe and Gihingamukungu). Nodal explants from in vitro growing plantlets were harvested and cultured on Murashige and Skoog media supplemented with 2.5, 5, 10, 20 and 40 μM, GA 3 . In a separate experiment, sucrose was evaluated at 30, 60, 90, 120, 150, 180 and 210 mM. For Ukerewe, the explants cultured on medium supplemented with 10 µM GA 3 recorded the longest (2.78 ± 0.36 cm) microshoots. . On the other hand, cultivar Gihingamukungu explants cultured on media supplemented with 2.5 GA 3 µM produced the longest ((3.23 ± 0.40 cm) microshoots. Nodal explants from the two cultivars cultured on media supplemented with sucrose 150 mM yielded the longest microshoots (2.51 ± 0.26 and 2.34 ± 0.24 cm, respectively). From the results of the current study, it can be concluded that for micropropagation of the cultivar Ukerewe 10 µM GA 3 should be used while 2.5 GA 3 µM should be used for micropropagtion of cultivar Gihingamukungu. The regenerated plantlets were successfully weaned in the greenhouse. The protocol developed in this research will open new prospects for massive propagation of the elite sweet potato cultivars in Rwanda.

Explants of two elite cooking banana cultivars, FHIA17 and INJAGI were collected from healthy source of stock plants growing in the field. Sterilization was evaluated using different concentrations (20, 30, 40, 50 and 60%) of a commercial bleach (JIK) for 25 min. Effects of cytokinins benzyl amino purine (BAP), 2-isopentenyl adenine (2iP) and kinetin each evaluated at 5, 10, 20, 24 and 40 µM and thidiazuron (TDZ) at 0.1, 0.5, 1 and 1.5 µM, on microshoot induction were investigated. Effects of auxins viz. napthaleneacetic acid (NAA), indole-3-acetic acid (IAA), 2,4-dichlorophenoxyacetic acid (2,4-D) and indole-3-butyric acid (IBA each evaluated at 5, 10, 20 and 40 µM) on rooting were tested as well. The highest (91%) numbers of clean explants were obtained when the explants were subjected to sterilization in 40% Jik for 25 min. The FHIA 17 explants cultured on MS media supplemented with 40 µM kinetin produced the highest (3.00±0.35) mean number of microshoots. On the other hand, INJAGI explants cultured on MS media supplemented with 0.1 µM TDZ yielded the highest mean number (1.84±0.24) of microshoots and the highest mean length (0.99±0.13). Rooting was achieved in all media supplemented with the auxins evaluated except on 2,4-D. These results have an important significance on the application of tissue culture in propagation of cooking bananas in Rwanda, which is highly desired to support the government policy of replacing old unproductive bananas with elite high yielding varieties.