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1.
Abrahamsen B Zhao J Asante CO Cendan CM Marsh S Martinez-Barbera JP Nassar MA Dickenson AH Wood JN 《Science (New York, N.Y.)》2008,321(5889):702-705
Peripheral pain pathways are activated by a range of stimuli. We used diphtheria toxin to kill all mouse postmitotic sensory neurons expressing the sodium channel Nav1.8. Mice showed normal motor activity and low-threshold mechanical and acute noxious heat responses but did not respond to noxious mechanical pressure or cold. They also showed a loss of enhanced pain responses and spontaneous pain behavior upon treatment with inflammatory insults. In contrast, nerve injury led to heightened pain sensitivity to thermal and mechanical stimuli indistinguishable from that seen with normal littermates. Pain behavior correlates well with central input from sensory neurons measured electrophysiologically in vivo. These data demonstrate that Na(v)1.8-expressing neurons are essential for mechanical, cold, and inflammatory pain but not for neuropathic pain or heat sensing. 相似文献
2.
Oppong Allen Dadzie Abu M. Ifie Beatrice Asante Maxwell D. Prempeh Ruth N. A. Abrokwah Linda A. Kubi Zipporah Appiah Marfo Esther A. 《Journal of Crop Science and Biotechnology》2023,26(2):167-178
Journal of Crop Science and Biotechnology - Maize (Zea mays L.) is the most important cereal crop in sub-Saharan Africa. However, its production is constrained by many factors including low yields... 相似文献
3.
Asante Maxwell Darko Adjah Kossi Lorimpo Annan-Afful Ebenezer 《Journal of Crop Science and Biotechnology》2019,22(2):123-130
Journal of Crop Science and Biotechnology - Even though there are abundant rice genetic resources, only a fraction is used in breeding programs leading to a narrow genetic base for improved... 相似文献
4.
A. K. Asante J. R. Barnett 《The Journal of Horticultural Science and Biotechnology》2013,88(5):781-790
SummaryGraft union formation in mango (Mangifera indica L.) was studied using light microscopy. The initial wound response was resin secretion which contributed mainly to the initial adhesion of the graft partners. Early callus formation occurred mainly from the rootstock with cells produced in definite rows, often in fan-like array. Parenchyma cells at the cortex, pith, xylem and phloem rays were all involved in callus formation. The establishment of the cambial bridge between the stock and scion was followed by the formation of a protective layer, the periderm across the callus edges. 相似文献
5.
J. Adjebeng-Danquah V. E. Gracen S. K. Offei I. K. Asante J. Manu-Aduening 《Journal of Crop Science and Biotechnology》2016,19(1):99-108
We evaluated the agronomic performance and diversity for morphological traits among a collection of local and exotic cassava genotypes in the Guinea Savannah agroecology of Ghana. One hundred and fifty cassava genotypes were assessed using 28 agro-morphological (18 qualitative and 10 quantitative) traits recorded from three months after planting until harvesting at 12 months after planting. There was significant genetic variability among the genotypes for most of the traits evaluated. High broad sense heritability was observed for most of the traits. Principal component analyses of the traits indicated that the first three principal component axes which accounted for more than 55% of the variation for 10 quantitative traits included storage root yield, number of leaves, harvest index, height at first branching, and plant height as the most important traits. A greater proportion of the phenotypic variances of plant height, height at branching, and harvest index were accounted for by genetic variances indicating that progress could made with selection. Pearson correlation analysis indicated that a number of traits were related to growth and yield of cassava in the Guinea Savanna ecology, making indirect selection for root yield possible. The study revealed ample genotypic variation in these morphological and agronomic traits to support selection for improved varieties. 相似文献
6.
Fifty cassava clones were studied using RAPD technique. They included landraces from the Wenchi, Nkoranza, Dormaa Ahenkoro
and Asonafo districts of the Brong Ahafo region of Ghana and three improved varieties. Genetic diversity of these genotypes
was studied using four primers, OPK-01, OPR-02, OPR-09 and OPJ-14. A total of 41 different bands were detected. Levels of
polymorphic fragments detected by the four primers ranged from 90% to 100%. By pooling bands from individual accessions together,
mean number of fragments per accession per primer ranged from 5.50±1.04 for the Improved cultivars to 7.00±0.71 for populations
of landraces from Dormaa. Mean frequencies of fragments not detected by the primers for the accessions were 0.524±0.12, 0.460±0.12,
0.561±0.12 and 0.523±0.12 for landraces from Wenchi, Nkoranza, Dormaa Ahenkro, Asonafo and the Improved varieties, respectively.
The grand mean frequency of individuals showing fragments not present in populations was 0.522±0.10. Genetic diversity estimates
ranged from 0.290 to 0.425 (mean 0.352±0.05) for primer OPK-01, 0.001 to 0.381 (mean 0.309±0.06) for primer OPR-02, 0.335
to 0.344 (mean 0.283±0.04) for primer OPR-09 and 0.152 to 0.352 (mean 0.261±0.07) for primer OPJ-14. Within the accessions
mean gene diversity estimates were 0.316±0.03, 0.293±0.09, 0.331±0.02, 0.322±0.07 and 0.247±0.03 for accessions from Wenchi,
Nkoranza, Dormaa Ahenkro, Asonafo districts and the Improved varieties, respectively. Interpopulational genetic divergence
ranged from 0.069 to 0.203 (mean 0.119±0.04). Rate of nucleotide substitution among the landraces was 9.8 per cent per site
per year, while that for the Improved varieties was 15 per cent.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
Wood density,phytomass variations within and among trees,and allometric equations in a tropical rainforest of Africa 总被引：1，自引：0，他引：1
M. Henry A. Besnard W.A. Asante J. Eshun S. Adu-Bredu R. Valentini M. Bernoux L. Saint-André 《Forest Ecology and Management》2010
The development of tree allometric equations is crucial to accurate forest carbon assessment. However, very few allometric equations exist for sub-Saharan Africa and as a result generalized allometric equations, often established for forests in other continents, are used by default. The objectives of this study were (1) to propose a sampling methodology and calculation procedures to assess biomass for tropical tree species of contrasted tree shapes in Africa, (2) to identify factors affecting within and between trees wood density, (3) to propose an allometric model that integrates these factors and (4) to evaluate the reliability of using generalized allometric equations in this type of forests. Models were developed to predict wood density and phytomass of the trees based on the harvesting of 42 trees from 16 species, representing three guild status in the wet evergreen forest of Boi Tano in Ghana. Results indicated that the wood density was highly influenced by the tree species, guild status, size of the tree and pith to bark distance. Dry mass of a tree was influenced by diameter at breast height, crown diameter and wood density. The wood density depends on the position of the wood within the tree and the guild status considered. The use of generalized allometric models in literature is limited by the specific climate zone, the consideration of tree height and species specific wood density. In considering those factors, using generalized allometric equations could result in an error of 3%. Further research should better consider the bigger trees and the influence of the topography and ecosystem history. 相似文献
8.
Nematode numbers were assessed at 2-week intervals in a coastal savanna soil amended with neem leaves and animal manure for
12 weeks under fallow conditions. The number of plant-parasitic nematodes decreased significantly with the application of
the neem-based amendments, whereas the number of non-parasitic nematodes increased.
http://www.phytoparasitica.org posting July 14, 2005. 相似文献
9.
J. Adjebeng-Danquah J. Manu-Aduening V. E. Gracen S. K. Offei I. K. Asante 《Journal of Crop Science and Biotechnology》2016,19(4):263-273
This study was carried out to assess genotypic variability in abscisic acid content, carbon isotope ratio, and their relationship to storage root yield and yield components in cassava under irrigation and moisture stress. The study involved 20 cassava genotypes arranged in randomized complete block design with three replications. Irrigation water was applied using a drip irrigation system with a discharge rate of approximately 5.33 L m-2 hr-1. Significant (P < 0.05) genotypic variability was observed for all physiological, growth, and yield traits assessed. Abscisic acid content was higher under stress than irrigation and negatively correlated with root yield (r = -0.45), harvest index (r = -0.43), and above-ground biomass yield (r = -0.20) indicating that it can be used as indirect selection criteria against unproductive genotypes. Carbon isotope ratio was significantly and positively correlated with above-ground biomass yield (r = 0.20) but not root yield (r = 0.09). Estimates of genotypic variability indicated high values for most of the growth and yield components but low heritability values for abscisic acid content, carbon isotope ratio, stomatal conductance, and root yield under stress conditions. However, higher estimates were recorded under irrigation and in the combined analysis. It was also found from this study that carbon isotope ratio influences above-ground biomass but not storage root yield under stress conditions. The results from this study provide useful information on the relationship between abscisic acid content, carbon isotope discrimination, and storage root yield in field-grown cassava. 相似文献
10.
The effect of shade and fertilizer application on nutrient uptake and dry matter (DM) partitioning in cocoyam was evaluated by growing the plant under different levels of shade and fertilizer application at Forest and Horticultural Crops Research Centre, Kade, within a period of 9 months. The shade levels used were 80%, 70%, and 50% shade, and full sunlight exposure. The fertilizer rates used were 112 kg/ha nitrogen, phosphorus and potassium (NPK) (15-15-15 120 kg/ha NPK (15-15-15) in a form) of mineral fertilizer, 112 kg/ha NPK organic fertilizer and no fertilizer (control). The split-plot design was used with shade levels as the main plot factor and fertilizer levels as the sub plot factor. The interaction effect of shade and fertilizer had a significant effect (p ≤ 0.05) on DM of cocoyam leaves, petioles, corm, and cormels as well as nutrient accumulation in plant parts. Cocoyam leaves of plants grown under 50–70% shade stored significantly higher (p ≤ 0.05) quantities of nutrients (1.51 ppm of N, 6.61 ppm of P, and 53.10 ppm of K) and accumulated more DM (71.30 g) than leaves of plants grown under full sunlight exposure which accumulated 1.37 ppm of N, 4.31 ppm of P, 26.06 ppm of K, and 30.7 g DM, at the two rates of the chemical fertilizer application. Under full sunlight exposure, significantly higher amounts of DM were accumulated in the corms and cormels at mineral fertilizer level of 112 kg/ha. At mineral fertilizer rate of 120 kg/ha, nutrient accumulation was significantly higher (p ≤ 0.05) in the corm and cormels (1.72 ppm of N and 7.72 ppm of P) of plants grown under full sunlight exposure than those grown under 70% shade level (0.6 ppm of N and 2.94 ppm of P). Nitrogen and phosphorus accumulation was significant in the petioles of plants grown under the 70% shade level at fertilizer rate of 120 kg/ha. It is recommended that cocoyam be grown under 50–70% shade at a fertilizer rate of 112–120 kg/ha for leaf production and under full sunlight exposure at 112 kg/ha (NPK) for cormel production. 相似文献