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Genetic and geographic variation in growth of Balanites aegyptiaca in Niger: comparing results from provenance/progeny tests in the nursery and field
Some tree improvement programs in Africa use nursery tests to investigate genetic and geographic variation in growth, but do they lead to the same conclusions as field tests? We investigated this question using provenance/progeny tests (12 provenances, 108 families) of Balanites aegyptiacafrom semi-arid Niger. The nursery test included treatments for time (12–16 months) and watering regime (reduced and normal). Family variation was significant for shoot diameter (Sdia), height (Sht), dry weight (Swt) and root dry weight (Rwt) in the nursery, and for tree height at 1 and 2 years (Fht-1, Fht-2) but not at 13.5 years (Fht-13.5) in the field. Provenance variation was significant only for root/shoot weight ratio (RSwt) in the nursery. Family mean Fht-1 and Fht-2 were positively correlated with all nursery growth variables except RSwt. Provenance mean Fht-2 was positively correlated with Sht, while provenance mean Fht-13.5 was negatively correlated with Swt and positively correlated with RSwt. Family mean survival at 13.5 years was positively correlated with Swt, Sdia, Fht-1 and Fht-2. Family mean Rwt, RSwt and Fht-2 increased from the more humid western to the drier eastern locations. -
Trend and Structure of Populations of Balanites aegyptiaca in Parkland Agroforestsin Western Niger
In Sub-Saharan Africa, trees and shrubs are intentionally cultivated with crops for multiple ecological and socioeconomical benefits [1-3]. Agroforestry systems are important for improving crop productivity, maintaining ecosystem integrity, and limiting capital resources depletion such as water, nutrients and soil [4,5]; mitigating the effect of global climate changes due to permanent tree cover that stores terrestrial carbon [6-9]; and reducing forest destruction by providing wood and non-timber products for human wellbeing [10]. Classically, agroforestry systems have been classified into six categories in which the woody plant component has the central role in the functioning of the agroforestry systems. These systems include crops under tree cover, agroforests, agroforestry in a linear arrangement, animal agroforestry, sequential agroforestry and minor agroforestry techniques [11]. The systems of crops under tree cover include all combinations of trees and crops in which the woody component creates an upperstorey covering the crops. -
Importance Ethnobotanique Et Des Menaces Sur Le Délice Du Boboye, Neocarya Macrophylla (Sabine) aPrance, (Chrysobalanaceae) Dans La Vallée Fossile
La présente étude, conduite dans la vallée fossile du Dallol Bosso, vise à connaitre la perception locale du niveau de menace sur l’espèce Neocarya macrophylla en vue de fournir des indicateurs de gestion durable du peuplement naturel. Pour ce faire, des enquêtes ont été menées dans deux zones agroécologiques. La collecte des informations a été effectuée à travers un questionnaire simple articulé autour du peuplement ligneux, les sources d’approvisionnement et les organes prélevés des espèces ligneuses alimentaires ainsi que les menaces qu’elles subissent et leurs causes. Il ressort que l’espèce la plus dominante est Neocarya macrophylla. Cette espèce est à usages multiples dont entre autres l’usage alimentaire, l’usage médicinal et l’usage énergétique.