scholarly journals Site-specific Nutrient Management for Lowland Rice in the Northern Savannah Zones of Ghana

2015 ◽  
Vol 3 (2) ◽  
pp. 109-117 ◽  
Author(s):  
W Dogbe ◽  
J. M Sogbedji ◽  
S. S. J Buah

A multi-location study was conducted to assess the nitrogen (N), phosphorous (P) and potassium (K) requirements of lowland rice (Oryza sativa L.) for a local variety Digang cultivated in the northern Savannahs of Ghana and offer site specific nutrient recommendations. Ten on-farm nutrient omission trials involving five rates of N, P and K combinations were conducted during 2010 cropping season in Sudan and Guinea Savannah agro-ecological zones. The treatments (kg/ha as N, P2O5 and K2O) comprised 0-0-0 (control), 0-90-90 (zero N), 90-0-90 (zero P), 90-90-0 (zero K), 90-90-90 (NPK). Grain yields were increased by applying fertilizer N, P and K in sufficient amounts (90 N, 90 P2O5 and 90 K2O kg/ha) to overcome deficiencies and maintain soil fertility. Nitrogen was a major limiting nutrient in the irrigated and rain fed lowlands in the northern Savannahs of Ghana. The N-limited yields varied between 832 and 1875 kg/ha, suggesting variability of N supplying capacity of the experimental plots. The impact of omitting N was different among the locations with the irrigated lowlands ecosystems in the Sudan Savannah that recorded the highest yield loss due to N omission and Guinea Savannah the least. Higher level of fertilizer N (118 kg/ha) was required in the irrigated lowland in the Sudan Savannah to achieve maximum yield compared with 52 to 79 kg N/ha in the rain fed lowlands of Guinea Savannah. Potash fertilizers have little effect on yield, especially in irrigated lowlands in the Sudan Savannah. Grain yield reductions due to nutrient deficiencies were more severe in the Upper West region than in Upper East region and Northern region. Higher levels of N in irrigated lowland ecosystems in the Sudan Savannah and higher P and K may be required in Upper West region in the Guinea Savannah than recommended for achieving higher yields on a sustainable basis.

2018 ◽  
Author(s):  
Hossam H Tayeb ◽  
Marina Stienecker ◽  
Anton Middelberg ◽  
Frank Sainsbury

Biosurfactants, are surface active molecules that can be produced by renewable, industrially scalable biologic processes. DAMP4, a designer biosurfactant, enables the modification of interfaces via genetic or chemical fusion to functional moieties. However, bioconjugation of addressable amines introduces heterogeneity that limits the precision of functionalization as well as the resolution of interfacial characterization. Here we designed DAMP4 variants with cysteine point mutations to allow for site-specific bioconjugation. The DAMP4 variants were shown to retain the structural stability and interfacial activity characteristic of the parent molecule, while permitting efficient and specific conjugation of polyethylene glycol (PEG). PEGylation results in a considerable reduction on the interfacial activity of both single and double mutants. Comparison of conjugates with one or two conjugation sites shows that both the number of conjugates as well as the mass of conjugated material impacts the interfacial activity of DAMP4. As a result, the ability of DAMP4 variants with multiple PEG conjugates to impart colloidal stability on peptide-stabilized emulsions is reduced. We suggest that this is due to constraints on the structure of amphiphilic helices at the interface. Specific and efficient bioconjugation permits the exploration and investigation of the interfacial properties of designer protein biosurfactants with molecular precision. Our findings should therefore inform the design and modification of biosurfactants for their increasing use in industrial processes, and nutritional and pharmaceutical formulations.


2018 ◽  
Vol 8 (2) ◽  
pp. 51-74
Author(s):  
Fonteh Athanasius Amungwa

This paper examines the impact of community education and challenges facing Centres for Education and Community Action as a rural development strategy in Cameroon. The study was conducted in the North-West Region of Cameroon, employing field observations, semi-structured interviews with key informants using a convenient sampling technique and through elaborate review of documents. These research instruments were blended into what is termed triangulation and the data collected was analysed descriptively. The main focus of qualitative analysis is to understand the ways in which people act and the accounts that people give for their actions. This paper posits that extreme dependence on the provision of Western formal education cannot solve the problems of a rapidly changing society like Cameroon, which is facing a long-term economic crisis and persistent unemployment issues of graduates. Consequently, education should be redefined in the context of the prevailing economic crisis to make it responsive to the aspirations of rural communities. Findings showed that community education had contributed towards rural development immensely but has suffered many challenges due to neglect of the field in the policy agenda. This paper recommends the integration of community education with formal education to facilitate group and community betterment in particular and rural transformation in general.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander Pralow ◽  
Alexander Nikolay ◽  
Arnaud Leon ◽  
Yvonne Genzel ◽  
Erdmann Rapp ◽  
...  

AbstractHere, we present for the first time, a site-specific N-glycosylation analysis of proteins from a Brazilian Zika virus (ZIKV) strain. The virus was propagated with high yield in an embryo-derived stem cell line (EB66, Valneva SE), and concentrated by g-force step-gradient centrifugation. Subsequently, the sample was proteolytically digested with different enzymes, measured via a LC–MS/MS-based workflow, and analyzed in a semi-automated way using the in-house developed glyXtoolMS software. The viral non-structural protein 1 (NS1) was glycosylated exclusively with high-mannose structures on both potential N-glycosylation sites. In case of the viral envelope (E) protein, no specific N-glycans could be identified with this method. Nevertheless, N-glycosylation could be proved by enzymatic de-N-glycosylation with PNGase F, resulting in a strong MS-signal of the former glycopeptide with deamidated asparagine at the potential N-glycosylation site N444. This confirmed that this site of the ZIKV E protein is highly N-glycosylated but with very high micro-heterogeneity. Our study clearly demonstrates the progress made towards site-specific N-glycosylation analysis of viral proteins, i.e. for Brazilian ZIKV. It allows to better characterize viral isolates, and to monitor glycosylation of major antigens. The method established can be applied for detailed studies regarding the impact of protein glycosylation on antigenicity and human pathogenicity of many viruses including influenza virus, HIV and corona virus.


2018 ◽  
Vol 38 (3) ◽  
pp. 210-215 ◽  
Author(s):  
Zhongjun Hu ◽  
Shulan Jin ◽  
Yizong Huang ◽  
Ying Hu ◽  
Wei Cheng ◽  
...  

2004 ◽  
Vol 8 (3) ◽  
pp. 449-459 ◽  
Author(s):  
I. A. Malcolm ◽  
D. M. Hannah ◽  
M. J. Donaghy ◽  
C. Soulsby ◽  
A. F. Youngson

Abstract. The spatio-temporal variability of stream water temperatures was investigated at six locations on the Girnock Burn (30km2 catchment), Cairngorms, Scotland over three hydrological years between 1998 and 2002. The key site-specific factors affecting the hydrology and climatology of the sampling points were investigated as a basis for physical process inference. Particular emphasis was placed on assessing the effects of riparian forest in the lower catchment versus the heather moorland riparian zones that are spatially dominant in the upper catchment. The findings were related to river heat budget studies that provided process detail. Gross changes in stream temperature were affected by the annual cycle of incoming solar radiation and seasonal changes in hydrological and climatological conditions. Inter-annual variation in these controlling variables resulted in inter-annual variability in thermal regime. However, more subtle inter-site differences reflected the impact of site-specific characteristics on various components of the river energy budget. Inter-site variability was most apparent at shorter time scales, during the summer months and for higher stream temperatures. Riparian woodland in the lower catchment had a substantial impact on thermal regime, reducing diel variability (over a period of 24 hours) and temperature extremes. Observed inter-site differences are likely to have a substantial effect on freshwater ecology in general and salmonid fish in particular. Keywords: temperature, thermal regime, forest, salmon, hydrology, Girnock Burn, Cairngorm


Ekonomika APK ◽  
2021 ◽  
Vol 316 (2) ◽  
pp. 15-25
Author(s):  
Dmytro Zherlitsyn ◽  
Andrii Skrypnyk ◽  
Nataliia Klymenko ◽  
Kateryna Tuzhyk

The purpose of the article is to determine with the help of econometric and optimization methods the priority strategies of agrarian business in the field of crop production and to compare with the existing leaders in the use of innovations in the field of crop production. Research methods. The study is based on the use of econometric analysis methods to build trends in grain yield dynamics in leading countries in the use of innovative agricultural technologies and optimization methods for the study of dominant strategies used by agricultural enterprises in crop production. Research results. As a result of using the declining marginal grain yield depending on the amount of costs, which are determined by the cost of importing technology per 1 ha, the optimal cost values for both maximum yield and maximum profit. It is shown that at certain time intervals the costs of farmers were excessively high not only in terms of profit optimization but also to optimize yields. It is assumed that taking into account the latest innovation trends, agribusiness will move to a strategy of profit maximization Scientific novelty. As a result of econometric analysis it is shown that the use as a target function of yield leads to a significant increase in the variability of this indicator, while a moderate increase in yield is accompanied by significantly less variability. Quantitative indicators of the impact of climate risks on grain yields in Ukraine have been obtained, which explain approximately 50% of the variance in the grain yield indicator in Ukraine. Practical significance. It is shown that the representation of marginal yield in the form of a decreasing linear function is confirmed in practice. Further research, which in the presence of detailed information on the production processes of individual enterprises can be conducted by panel regression (observation points are spaced in space and time), can provide a more detailed picture of the efficiency of individual production components in their areas of interaction. Tabl.: 4. Figs.: 3. Refs.: 19.


2021 ◽  
Author(s):  
Zach S Grover ◽  
Rachel L Cook ◽  
Marcela Zapata ◽  
J Byron Urrego ◽  
Timothy J Albaugh ◽  
...  

Abstract Calcium (Ca) is a critical plant nutrient typically applied at the time of planting in intensive Eucalyptus plantations in South America. At two sites in Colombia, we examined (1) calcium source by comparing growth after application of 100 kg ha−1 elemental Ca as lime or as pelletized highly reactive calcium fertilizer (HRCF) compared to a no application control, and (2) Ca rate by applying 0, 100, 200, and 400 kg ha−1 elemental Ca as HRCF with the addition of nitrogen, phosphorus, potassium, sulfur, and boron (NPKSB). We assessed height, diameter, and volume after 12 and 24 months. There were no growth differences from Ca source at the 100 kg ha−1 rate. We found increased volume after 24 months at the “Popayan” site with 200 and 400 kg ha−1 Ca HRCF+NPKSB treatments (112 and 113 m3 ha−1, respectively) compared to control (92 m3 ha−1), a 22% increase. In contrast, volume did not differ after 24 months at the “Darien” site, ranging from 114 m3 ha−1 in the 0 kg ha−1 Ca HRCF+NPKSB treatment to 98 m3 ha−1 in the control. Differences in response are likely due to soil characteristics, such as organic matter, emphasizing the importance of identifying site-specific nutrient deficiencies. Study Implications: Operational applications may be over- or under-applying calcium carbonate in Eucalyptus plantations in South America. In the first two years of a seven-year rotation located in volcanic soils in Colombia, we found that one site with more organic matter at a greater depth did not need Ca additions, whereas the other site required greater than current operational applications to optimize productivity. Ca application rate trials across a gradient of soil conditions could establish critical values and improve recommendations of appropriate Ca application rates and emphasize the importance of understanding site-specific soil conditions to produce effective fertilization regimes.


1970 ◽  
Vol 32 (1) ◽  
pp. 41-53
Author(s):  
YN Jolly ◽  
A Islam ◽  
SB Quraishi ◽  
AI Mustafa

The impact of various dilutions (2.5, 5, 10, 25 and 50%) of paint industry effluent on physico-chemical properties of soil and the germination, growth and dry matter productions of corn (Zea mays L.) and rice (Oryza sativa L.) have been studied. The effluent was acidic and had low BOD and COD values because of its low content of suspended solid. It contained high concentration of calcium, medium concentrations of nitrogen, sodium, potassium, sulphate, chloride and low concentrations of phosphorus, magnesium and bicarbonate. The trace element like Mn, Ni, Cu, Zn and Pb were measured in the μg L-1 level. On irrigation of soil with the effluent an increase in the water soluble salts, pH, electrical conductivity, cation exchange capacity, nitrogen, phosphorus potassium, sodium, calcium, magnesium and iron contents of the soil for effluent concentrations of 2.5, 5 and 10% were observed but all these parameters were found to decrease on treatment of the soil with the effluent concentration of 25% and above. The effluent of the lower concentrations (2.5, 5 and 10%) enhanced the growth of both crops. However, negative effects on seed germination, dry matter production and the yield of both crops were found for the effluent concentration of 25% and above. doi: 10.3329/jbas.v32i1.2441 Journal of Bangladesh Academy of Sciences, Vol. 32, No. 1, 41-53, 2008


Scene ◽  
2018 ◽  
Vol 6 (2) ◽  
pp. 133-151 ◽  
Author(s):  
Julie Marsh

This article reflects on the significance and impact of Assembly, a site-specific research project made and exhibited in Birmingham Central Mosque, Brick Lane Mosque and Old Kent Road Mosque from 2016 to 2020. Assembly provided an opportunity for Muslims and non-Muslims to experience Jumu’ah prayer first-hand via the site performances, which temporarily dissolved the religious/social boundaries of each mosque. Each performance highlighted the differences and relations between each site, furthering ideas of performativity in Muslim prayer spaces. This article summarizes the impact reported by each mosque community as well as reflecting upon the relationships built within the wider community.


Sign in / Sign up

Export Citation Format

Share Document