Occurrence of cucumber mosaic virus within tomato seed lots

Tomato (Solanum lycopersicum L.) is an important crop whose fruit is widely consumed globally. However, its yield is affected by cucumber mosaic virus (CMV) and can cause total crop failure. The virus is mainly transmitted by aphid vectors, but data on its spread via seeds are limited. Thus, the occurrence of CMV within tomato seed lots obtained from different sources was investigated. Seven tomato accessions and varieties were collected from five sources and evaluated for seed transmission of CMV. One hundred seeds each were sown in a plastic tray, and germination rates were recorded. The incidence and severity of virus symptoms were observed at 3, 6, and 9 weeks after sowing (WAS), while leaves were tested for CMV using antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA). The germination percentage ranged from 60% in accession 'V4' to 92% in 'UC-82B'. Infection rates were 100%, 71.74%, 70.31%, 45.90%, and 8.33% in 'Roma-VF', 'UC-82B', 'NG/AA/SQ/09/053', 'V2', and 'V4', respectively. 'Kerewa' and 'Alausa-Long' exhibited zero infection rates and tested negative for CMV using ACP-ELISA. Eighty percent of test plants became symptomatic at 6 and 9 WAS, although accession 'NG/AA/SQ/09/053' tested positive for CMV despite showing no symptoms. Tomato seeds from commercial stores, research institutes, and farmers' fields tested positive for CMV, while seeds from the market were negative at 9 WAS. The results from this study confirm the transmissibility of CMV through seeds in tomatoes, although the rate of seed transmission is cultivar dependent

USPOREDBA PROCJENE EKONOMSKE KORISTI ZEMLJANIH BAZENA RIBNJAKA I BETONSKIH SPREMNIKA U AKVAKULTURNOM PODUZETNIŠTVU DRŽAVE OYO U NIGERIJI

The study focused on the comparative evaluation of economic benefits of earthen fish ponds and concrete tanks in aquaculture enterprises in Ibadan, Oyo state. Primary data were collected with the aid of structured interview schedule, administered through personal interviews and observations to elicit information from 100 fish farmers using purposive and convenience sampling procedure. Data collected were analyzed using descriptive, budgetary and inferential statistics. The study revealed that the mean age, male, married, household size, educated and fish farming experience were 41 years, 83.0%, 87.0%, 5 persons, 96.0% and 8 years, respectively. Earthen fish ponds users earned mean revenue of N3,322,189.85 with gross margin of N2,188,397.89 while concrete tank users earned N2,412,271.08 with gross margin of N1,413,299.46. The results showed profitability indices (0.61 and 0.47), Variable Cost ratio (0.35 and 0.30), Benefit Cost Ratio (2.55 and 1.89), Gross ratio (0.40 and 0.54) and Expenses structure ratio (0.13 and 0.23) for both the earthen ponds and concrete fish tanks, respectively. There were significant differences (t = 42.53, p≤0.05) between the profit level of earthen fish ponds and concrete tanks. Major constraints affecting economic status of the respondents were high cost of quality feed, insufficient funds, poaching and poor marketing channel. In conclusion, aquaculture is a more profitable and viable business regardless of the culture system. Government should assist the fish farmers by subsidizing feeds cost, granting and monitoring of loan.Temelj ovog istraživanja bila je usporedba procjene ekonomske koristi zemljanih bazena ribnjaka i betonskih spremnika u akvakulturnim poduzećima grada Ibadana u državi Oyo. U izboru 100 uzgajivača ribe korištena je kombinacija svrsishodnog i praktičnog uzorkovanja, a uzgajivači su bili podvrgnuti strukturiranom intervjuu radi prikupljanja primarnih podataka u svrhu deskriptivne statistike, proračunske tehnike i inferencijalne statistike. Istraživanje je rezultiralo sljedećim podacima: prosječna životna dob bila je 41 godina, muškaraca je bilo 83,0%, oženjenih 87,0%, u većini slučajeva bilo je 5 članova kućanstva, obrazovanih je bilo 96,0%, a iskustvo uzgoja riba kod ispitanika bilo je 8 godina. Korisnici zemljanih bazena ribnjaka imali su srednji prihod od N3,322,189.85 s bruto maržom od N2,188,397.89, dok su korisnici betonskih spremnika zaradili N2,412,271.08 s bruto maržom od N1,413,299.46. Indeks profitabilnosti bio je 0,61 i 0,47, varijabilni omjer troškova 0,35 i 0,30, omjer troškova i koristi 2,55 i 1,89, bruto omjer 0,40 i 0,54, a omjer strukture troškova bio je 0,13 i 0,23. Značajna je razlika između razine profita od zemljanih ribnjaka i betonskih spremnika (t = 42,53, p ≤ 0,05). Glavne prepreke koje utječu na ekonomski status ispitanika bili su visoki troškovi kvalitetne prehrane, neadekvatnost fondova, krivolov i loš marketing. Zaključno, akvakultura je isplativo i održivo područje poduzetništva, bez obzira na kulturni sustav. Vlada bi trebala pomoći uzgajivačima ribe subvencioniranjem troškova prehrane, odobravanjem i praćenjem kredita

Spatial Variability of VHF FM Radio Signals with Surface Refractivity Values in Niger State, Nigeria

Radio refractivity N exerts considerable influence on radio signals at Very High Frequency (VHF) and higher frequency bands. In particular, surface refractivity correlates positively with radio field strength, and knowledge of its temporal and/or spatial variability is important in predicting performance of terrestrial radio networks, especially at VHF frequencies. In this work, measurement of electric field strength of Frequency Modulated (FM) radio signals in Niger State, Nigeria was carried out at the onset and peak of the wet season; variation of surface radio refractivity was obtained in Minna, Niger State based on concurrent measurement of surface air temperature, pressure and relative humidity. Variation of electric field strength of FM radio signals in the wet season is found to agree in general with the observed variation of surface radio refractivity, Ns, in Niger State, Nigeria. Keywords: Electric field strength, surface radio refractivity, propagation

Synthesis, Characterization and Antimicrobial Activities of Some Nicotinamide – metal Complexes

Some transition metal complexes of nicotinamide have been prepared and characterized using melting point, conductivity measurement, infrared, electronic, HNMR and atomic absorption spectroscopic methods. . The antibacterial and antifungal studies of the metal complexes and the ligand have been evaluated against Escherichia coli, Staphylococcus and Bacillus subtilis , Aspergillus flavus, Aspergillus niger and penicillum species. It was found that nicotinamide formed stable metal complexes with these metal ions. The analysis of the spectroscopic data shows that nicotinamide act as monodentate, coordinating through the nitrogen atom of the pyridine ring. All the complexes exhibit 4- coordinate geometry. The results of the antimicrobial studies showed that the metal complexes have higher inhibitory activity than the original nicotinamide against the tested bacteria and fungi species.Keywords: Synthesis, Metal complexes, Nicotinamide, Antibacterial, Antifunga

Design and Construction of an Arduino - Based Solar Power Parameter-Measuring System with Data Logger

Accurate monitoring and measurement of solar photovoltaic panel parameters are important for solar power plant analysis to evaluate the performance and predict the future energy generation. There are always challenges of getting such data readily available due to huge amount of money to be spent on state of the art equipment or the purchase of reliable satellite weather data. This study aimed at the development of a cost-effective parameter-measuring system for a solar photovoltaic panel using Arduino microprocessor board. The systems measure five parameters, including voltage, current, light intensity, temperature, and pressure. The hardware circuit was designed to link different sensors with the Arduino board and the measured data were in turn were documented into a computer for further analysis. The accuracy of the constructed device was ascertained by comparing the measured parameters with that of conventional standard measuring instruments which shows good agreement. The measured parameters show that the output energy generation from solar photovoltaic panel largely depends on the solar irradiance and temperatur

Modelling of the equatorial ionospheric E-layer based on cos<img src='/image/spc_char/lembda.gif' border=0> index

205-212Daytime hourly values of the critical frequency of the ionospheric E-layer, oE, obtained at Ouagadougou Ionospheric Observatory (12.4°N, 1.5°W) in Burkina Faso, West Africa, an equatorial station, during the solar cycle 22 (1985 – 1995) have been used to develop a model based on solar zenith angle through cosc index factor using the relation oE = a (cos)n, The average value of the diurnal cos index, n, at Ouagadougou was found to be 0.30 for both low and high solar activity. The model was tested with oE data from Korhogo (9.3°N, 5.4°W) in Cote-d’Ivoire, another equatorial station, and there is good agreement between the model and observations. The validity of the oE model was also compared with predicted values by IRI-2012 model and good agreement has been observed. The percentage difference, when oE observed compared with IRI-2012 model, was found to be within ±10% for both equinoxes and solstices for the two levels of solar activity. </span

Bowen ratio estimation of surface energy fluxes in a humid tropical agricultural site, Ile-Ife, Nigeria

213-218The Bowen ratio energy balance (BREB) is a micrometeorological technique often used for estimating the surface energy fluxes (i.e. latent heat, sensible heat fluxes) because of its simplicity, robustness, and affordability. The same method has been applied in this study to partition the available energy (Rո – G₊) at a humid tropical agricultural site in Ile-Ife, Nigeria (7º33'N, 4º33'E) during the transition period (wet and dry) between 25 and 29 Feb. 2004. Results obtained for the diurnal variations of the energy fluxes in relation to changing surface condition are satisfactory. For the relatively dry days, the sensible heat flux is comparatively of the same magnitude as the latent heat flux except on a day when it was a little higher, but it is less during the wet days. It is therefore obvious from this study that for a tropical weather, evaporation is the next essential factor after radiation in the energy balance due to the prevailing humid conditions in the zone

Aspergillus niger, fungal pectinase, pomelo peels, solid state fermentation

Aims: This study investigated the antibiotic susceptibilities of avian pathogenic Escherichia coli (APEC) isolates from layer chickens that died of colibacillosis, in the 6 states of Southwest Nigeria. Methodology and results: From bacteriological cultures of dead layers with suspected colibacillosis, 509 APEC isolates were identified by Gram staining, microscopy, and biochemical reactions, and tested by the Kirby-Bauer disc diffusion method for susceptibility to 9 human and veterinary antibiotics: Streptomycin (Str, 200 µg); Nitrofurantoin (Nit, 300 μg); Augmentin (Aug, 30 µg); Amoxicillin (Amo, 25 µg); Chloramphenicol (Chl, 30 µg); Gentamicin (Gen, 10 µg); Tetracycline (Tet, 25 μg); Ofloxacin (Ofl, 5 µg); and Fosfotrim (Fos, 30 μg). The APEC isolates were highly resistance to Amo (99.2%), Chloramphenicol (96.5%), Tet (91.4%) and Ofl (86.4%); moderately resistant to Gen (67.2%), Aug (63.5%), Nit (51.7%) and Fos (37.9%); while 14.3% of the isolates were resistant to Str at the test concentration of 200 µg, equivalent to ten times the normal disc test concentration. Overall, 39 antibiotic resistance patterns were observed, and more than 84.68% (n = 431) of the APEC isolates were multi-drug resistant. Conclusion, significance and impact of study: These results indicate that there is widespread misuse of antimicrobials in the poultry industry in Southwest Nigeria, and portend a high failure rate for the treatment of avian colibacillosis in the region. Owing to the public health importance of multidrug resistant bacteria that arise from animal production systems, there is need for exhaustive review of the regulatory framework guiding the supply and use of veterinary antimicrobials in Nigeria

Freshness evaluation of Sharptooth catfish (<em>Clarias gariepinus</em> burchell 1842) stored in ice fish box^™ using quality index method

Fish tend to spoil quickly after harvesting during handling, transportation and storage, thus needs intervention. Nigerian Stored Products Research Institute developed an insulated box for handling, transportation and storage of fresh fish. However, evaluation of fish quality including freshness is mostly done with the analysis of chemical and microbial parameters that are time consuming and costly. In Nigeria, no specific method exists for evaluating the freshness of fish when landed and its shelf life on ice. Sharptooth catfish (Clarias gariepinus) stored in two models of Ice Fish Box™ were assessed for freshness during storage using Quality Index Method (QIM) based on a structured scale for quality measurements to provide accurate and precise information in terms of freshness and to predict remaining shelf-life of catfish. The Quality Index scores had a correlation of 0.9839 and 0.9301 with new and old ice boxes, respectively and there was linearity between period of storage and quantity of ice with total scores of attributes such as colour, skin, gill, firmness and odour decreasing with storage time. Catfish had a shelf life of 48 hours in Ice Fish Box without further addition of ice. Based on this outcome, QIM can be used as an on- the spot evaluation tool to evaluate freshness of fish and a useful guide for fishermen and setting standards for other stakeholders in the value chain which may enhance better post-harvest management of fish