Dry-season sorghum is a type of sorghum whose establishment ends at the end of the rainy season and its development takes place during the dry and cold harmattan period. Its root system is particularly well developed with deep penetration for water withdrawal. This study was conducted to assess the level of genetic diversity present among dry-season sorghum in Chad’s Sudanese zone using phenotypic traits, and to identify new sources of drought tolerance that could be used in sorghum breeding programs. A high variability in qualitative traits was observed except for the botanical race which showed that all cultivars were of durra race. It was also observed that most cultivars had compact panicles (66.67%), mostly black glumes (66.67%), glume hairiness (58.33%) and did not have aristation (91.67%). Most qualitative traits showed a coefficient of variation of less than 30%, and the analysis of the variance showed that at 0.1% probability, there were significant differences between cultivars for all traits except botanical race. It was observed that the potential productivity of dry-season sorghum of this collection was strongly related to their staygreen characteristic; a trait of enormous importance in breeding for postflowering drought tolerance in sorghum. Plant height was highly heritable (91.9%), followed by the peduncle length (90.2%), panicle length (87.5%) and the internodes number (86.5%). Structuring of diversity separated the cultivars into four statistically distinct groups; with group 2 clustering cultivars with panicle productivity, early maturity and high staygreen, and other traits that contribute to the performance of cultivars. The findings will help to enhance the selection and production of dry-season sorghum in Chad and also provide alternative sources for staygreen introgression into the larger sorghum breeding community.

RESUMEAu Burkina Faso, le sorgho à grains sucrés [Sorghum bicolor (L.) Moench] est une culture marginale dont les grains sont consommés frais au stade pâteux. Afin de recueillir les connaissances paysannes sur la gestion du sorgho à grains sucrés et de déterminer le niveau et la structuration de la diversité agromorphologique de ces sorghos du Burkina, une prospection-collecte d'accessions a été réalisée dans les quatre zones agro-écologiques du pays. Au total, 126 accessions ont été collectées dans 102 villages parmi lesquelles 97 ont été caractérisées à partir de 12 caractères qualitatifs et 12 quantitatifs suivant un dispositif blocs de Fisher à trois répétitions. L'étude a montré d'une part que ce sorgho est cultivé surtout dans les champs de case et principalement par l'ethnie mossi et d'autre part que la nomenclature paysanne est basée surtout sur les caractères phénotypiques visibles. Une importante variabilité agromorphologique a été observée au niveau de tous les caractères quantitatifs et une répartition des 97 accessions en 3 groupes : les accessions à cycle long et à rendement grains élevé, les accessions à cycle court et à rendement grains faible et les accessions à cycle et rendement moyens. Les races botaniques caudatum (45,4 %) et caudatum-guinea (48,5%) sont les plus prédominantes dans la collection. Cette diversité génétique est un atout important pour les programmes de sélection et d'amélioration génétique du sorgho.

Assessment of agromorphological diversity and genetic parameters in Northern of Burkina Faso' sweet grains sorghum [Sorghum bicolor (L.) Moench]. Objective: The study was conducted to determine the level of genetic diversity of Northern of Burkina Faso' sweet grains sorghum and to estimate genetic parameters in order to identify appropriate breeding strategies for the crop improvement. Methodology and Results: Accessions were grown according to a device in Blocks of Fisher with three replications. Results showed an important morphological diversity structured around vegetative and yield traits. Accessions were distributed into four groups based on plant height and grains yield. The difference between phenotypic and genotypic variances was lower for all characters. High broad sense heritability estimates recorded for all characters. High heritability combined with high expected genetic advance were observed for yield traits. However, high heritability and low expected genetic advance were observed for vegetative traits. The cycle presents a high broad sense heritability and moderate expected genetic advance. Conclusion and Application: Four groups obtained are pools of various genes which could be used as broodstock for varieties development that meet expectations of farmers. The genetic diversity in Northern of Burkina' sweet grains sorghum could be exploited in sorghum breeding programs. Genetic parameters obtained suggest that improvement of sweet grains sorghum by a simple selection method is possible.

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KEYWORDS Cleome gynandra Selection Agromorphological characterization Burkina Faso ABSTRAC TPresent study was aimed to understand the scientific basis of the farmer's nomenclature of the local varieties of Cleome gynandra L. and to identify the characters of interests that can be used for the varietal improvement of the species. A survey was carried o ut in five cities of Burkina Faso with 56 producers of C. gynandra with the help of semi-structured interviews to identify the preferential characters. Furthermore thirty accessions were collected and evaluated in July 2014 at Gampela according to randomized complete block design with seventeen variables. T he study revealed that in the denomination of local varieties, the farmers use agromorphological characters such as the color of the stem, leaves and the vegetative cycle of the plant. It was also revealed that the selection of plant in the vegetable garden s is preferred for the green color of the stem, leaves, long vegetative cycle, height of the plant, dimensions of the leaves and the number of primary branches. T hese were the selective interests for the farmers identified during the survey. T he study also revealed that the process of selection is more advanced in Ouagado ugo u, where the demand is very high and where the consumers are more as compared to the other localities where the choice of the p lant has just began for consumption. T he results of this study have permitted to undertake the varietal improvement of the species according to the needs of the producers whose majority have a particular preference for the green ecotypes with long cycle.