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71.
72.
Leucaena leucocephala failed to nodulate effectively with promiscuous indigenous rhizobia with which Mucuna pruriens nodulated effectively. Mucuna pruriens was adequately established and well nodulated due to the presence of favourable climatic and edaphic factors which enhanced its establishment in the humid/moist savanna zone of Nigeria. The microsymbiont for M. pruriens seems to thrive more in an alkaline rhizosphere. Introduction of M. pruriens into the farming system in Nigeria may serve as a low input agricultural system, which is not only sustainable but also economically viable.  相似文献   
73.
This paper attempts some preliminary evaluation of the potential of agroforestry techniques as a forestry strategy for controlling atmospheric CO2—a critical greenhouse gas. The end-use scenario that attempts to meet the wood and related needs of the nation while mitigating climate change was adopted. The net emission estimate for the Forestry Sector in 1990—the base year for the study—was 9.5 million tonnes of carbon (MtC). Based on this figure, projections into the year 2030 gave cumulative net emissions of 427.4 and 580.5 MtC at 1.3% and 2.6% deforestation rates respectively. However, mitigating with agroforestry techniques, assuming that about 76% of the estimated 39.5 million ha of farmland in the country is committed to a variety of agroforestry systems, the results show that a total of 1530 MtC can be withdrawn from the atmosphere by the year 2030. The paper concludes that there is a reasonable case for the use of agroforestry techniques in the country, both as a means of sustaining soil productivity and as a strategy for mitigating climate change.  相似文献   
74.
BackgroundLoiasis is currently receiving attention as a disease of public health importance because of the possibility of increased risk of developing neurologic serious adverse event following mass ivermectin treatment against onchocerciasis in individual co-infected with Onchocerca volvulus and Loa loa.Conclusions/SignificanceLow prevalence of onchocerciasis and loiasis co-infection in this study suggests that loiasis may not pose a serious epidemiological threat to the continuous distribution and sustainability of ivermectin for the treatment of onchocerciasis. Evaluation of the interruption of onchocerciasis transmissions in this region using all the indicators set forth by WHO is therefore suggested.  相似文献   
75.
The diversity of trees 5 cm in diameter and above at breast height was studied at five sites within the Nigerian rainforest. The sites were Gambari, Oban, Omo, Owan and Sapoba forest reserves. Diversity was measured in terms of similarity and heterogeneity and explored at beta and gamma levels. Over 315 species were encountered during the study. In terms of species richness, there are 80, 226, 163, 137 and 159 species in Gambari, Oban, Omo, Owan and Sapoba, respectively. The occurrence of the species showed that, while 26 species are common to all the sites, 62, 17, 15, 8 and 6 species are restricted to Oban, Omo, Sapoba, Gambari and Owan, respectively. Ordination by detrended correspondence analysis indicated gradients along the first two axes. The first axis reflecting rainfall gradient which decreases from Oban through to Sapoba, Owan and Gambari. The second axis showed a separation of Omo, and Owan and Sapoba. This suggests a gradient of soil parent materials, the former site is on the basement complex while the latter is on the cretaceous rock. It is suggested that each forest should be managed based on its particular characteristics, such as species composition and abundance. Thus, forests with high species diversity but fewer numbers of individuals, such as in Oban, should be earmarked for conservation while species-rich forests with relatively more economic species, as in Sapoba and Omo, should be managed for sustained timber production. Floristically poor forest, such as those in Gambari and Owan, should be converted to plantations of fast growing species but with care taken to avoid exposing such sites to soil erosion.  相似文献   
76.

Background  

Current data on the pattern of parkinsonism and Parkinson's disease in Nigerians are sparse.  相似文献   
77.
Biological Trace Element Research - In this pioneering effort on Nigerians, the arithmetic means, ranges, and standard deviations for the concentrations of the 13 elements, Br, Ca, Cl, Cu, Fe, K,...  相似文献   
78.
This study examined the performances of 21 cassava cultivars in two cropping seasons on the field against root rot disease and the yield in cassava-maize intercrop. Data were collected on number of root/plant, weight of root (t/ha) and disease severity (DS) on rotted roots at 12 and 16 months after planting (MAP), respectively. There were significant (P ≤ 0.05) differences for DS at 12 and 16 MAP in both seasons with cultivar TMS 97/JW2 having the least DS score. TMS 97/JW2 was resistant to the root rot pathogen, while eleven other cultivars were moderately resistant to the disease at 16 MAP. There was no consistency in the roots weight for the cultivars over the two cropping seasons but higher roots weight was recorded at 16 MAP than 12 MAP with different cultivars having highest roots weight at these periods. Intercropping maize with cassava does not have any management potential on root rot development.  相似文献   
79.
A study was carried out to evaluate the chemical composition, in vitro apparently and truly degraded dry matter (DM), utilizable crude protein at the duodenum (uCP) (total CP at the duodenum minus endogenous CP), methane production, and short chain fatty acid production of haulms of six cowpea varieties. The study was arranged in a 2 × 2 × 2 factorial design, with three replicates. Three improved (ITA2, ITA6 and ITA8) and three commercial (Oloyin, Peu and Sokoto) cowpea varieties harvested during wet and dry seasons were used for the study. After an initial gas test to evaluate 96 h gas production profiles of haulms with and without polyethylene glycol (PEG), the time to half maximal gas production was calculated and a second incubation conducted with fermentation stopped at substrate specific half time (t1/2) and 24 h for each substrate. True DM degradability was measured from incubated residues and combined with gas volume to estimate the partitioning factor. Crude protein flow to the duodenum was estimated by combining gas volume with the measured ammonia nitrogen in the incubated fluid. Addition of PEG did not have any effect (P>0.05) on all the variables determined. Interaction between group (improved vs. commercial) and season was observed for CP (P=0.002), lignin (P=0.003) and hemicellulose (P=0.030) contents of the haulms. A group × season interaction was also observed for some of the variables at both substrate specific t1/2 and 24 h. Commercial cowpea haulms had greater (P=0.002) microbial mass and produced less (P<0.05) methane than the improved cowpea haulms. The improved cowpea haulms were less (P<0.001) degraded in the rumen and as a result ensured greater (P<0.001) amount of uCP. The results validated that cowpea haulm is an important agro-based by-product that is adequate in protein and energy to sustain ruminant animal production in Nigeria and other Sub-Saharan African countries during the extended dry season.  相似文献   
80.
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