20 research outputs found
Influence of the origin of stem cutting, season of collection and auxin application on the vegetative propagation of African Sandalwood (Osyris lanceolata) in Tanzania: scientific paper
An investigation into the possibility of propagating O. lanceolata through stem cutting was carried out at Tanzania Tree Seed Agency, Iringa Zone, Tanzania. The aim was to test the potential of stem cuttings in providing an alternative/supplement to the use of seeds that are constrained with germination and storage problems. Three treatments were investigated on the rooting success and subsequent nursery performance of the cuttings: the effect of season at which cuttings are collected i.e. December, February, June and September; the effect of origin of stem cutting in a shoot, i.e. basal and terminal portions; and the effect of different levels of IBA as root promoters, i.e. 0, 50, 100 and 150 ppm. The results revealed that stem cuttings collected from the sprouting stumps have a potential to be used in propagating O. lanceolata. Season at which cuttings are collected; origin of the stem cuttings in a shoot and application of auxins influenced the rooting success. Stem cuttings collected in September, originating from the basal portion had the best rooting (43.8 + 3.9%). This is possibly related to the high levels of stored food in the plant after undergoing active photosynthesis during the rain season, November-May. Auxin application in interaction with the season at which cuttings were collected enhanced the number of cuttings that rooted, the number of roots formed (13 + 0.4), the length (14 + 0.3 cm) and biomass of roots (6.95 + 3.9 g) produced. The concentration to be applied for effective rooting depended on the season at which cuttings were collected. Of the origin of stem cuttings, basal portions had better rooting than the terminal portion. The high nutrition status and low nitrogen content of basal portions may play a role in enhancing their performance. Thus when raising O. lanceolata from stem cuttings, best rooting is obtained from those raised between June and September using cuttings from the basal origin of the juvenile shoots. Application of IBA between 50 and 100 ppm further enhances rooting success.
Key Words: Osyris lanceolata, African sandalwood, Stem cuttings, Collection season, Stem origin, IBA application, Rooting success
Southern African Forestry Journal Vol.201, 2004: 13-2
Comparison of the Chemical Compositions of the Essential Oils from the Aerial Parts, Fruits and Roots of Nigerian Laportea aestuans
Reactivity, characterization and mechanical performance of particleboards bonded with tannin resins and bio hardeners from African trees
An electrochemical and structural investigation of silicon nanowires as negative electrode for Li-ion batteries
Multi-variate analysis of factors governing the pharmacokinetics of exogenous factor VIII in haemophiliacs
A novel antiplasmodial 3′,5′-diformylchalcone and other constituents of Friesodielsia obovata
Stable cycling of double-walled silicon nanotube battery anodes through solid–electrolyte interphase control
Although the performance of lithium ion-batteries continues to improve, their energy density and cycle life remain insufficient for applications in consumer electronics, transport and large-scale renewable energy storage(1-5). Silicon has a large charge storage capacity and this makes it an attractive anode material, but pulverization during cycling and an unstable solid-electrolyte interphase has limited the cycle life of silicon anodes to hundreds of cycles(6-11). Here, we show that anodes consisting of an active silicon nanotube surrounded by an ion-permeable silicon oxide shell can cycle over 6,000 times in half cells while retaining more than 85% of their initial capacity. The outer surface of the silicon nanotube is prevented from expansion by the oxide shell, and the expanding inner surface is not exposed to the electrolyte, resulting in a stable solid-electrolyte interphase. Batteries containing these double-walled silicon nanotube anodes exhibit charge capacities approximately eight times larger than conventional carbon anodes and charging rates of up to 20C (a rate of 1C corresponds to complete charge or discharge in one hour).N