36 research outputs found
Effects of two rhizobacteria inoculants on maize growth performance at different concentrations of glyphosate
The use of Rhizobacteria as biofertilizer is on the increase due to the ability of some of the bacteria to solubilize some insoluble essential nutrients in the soil and produce phytohormones necessary for plant growth. The effectiveness of two plant growth promoting rhizobacteria (Bacillus cereus and Pseudomonas aeruginosa) in plant growth promotion at different concentrations of glyphosate were evaluated. Some agronomic parameters such as plant height, size of girth, number of leaves on the screen house and field were measured and recorded. The results of the effects of P. aeruginosa on the height of maize at different concentrations showed that the plants inoculated with the isolates and planted on the soil without glyphosate (control) recorded the highest height on the 2nd (34.9 cm), 4th (52.45 cm), 6th (61.17 cm) and 8th (66.25 cm) weeks after planting, when compared to those planted on the soil spiked with different concentrations of glyphosate. The effects of the isolates on the size of girth of maize on the soil spiked with different concentrations of glyphosate showed the highest girth size on the soil inoculated with P. aeruginosa eight weeks after planting (8 WAP) with a girth size of 2.0cm and least at 14.4 mg/ml of glyphosate with a girth size of 1.2 cm at 8 weeks after planting. Similar trend was observed on the soil inoculated with B. cereus (without glyphosate) with the highest girth in the 2nd and 4th WAP (1.02 and 1.42 cm, respectively). The results of our field studies showed no significant difference (P≤0.05) in the height and number of leaves of the maize at different treatments and time (weeks after planting). Similar trend was observed i n the yield of maize. This study has shown that these isolates can be useful as biofertilizers especially in the absence or at low concentration of glyphosate.
Keywords: Rhizobacteria, maize, Inoculants, Plant-growth-promotion
Effects of Environmental factors on the Growth and Proliferation of Yeasts
Yeast is one of the organisms that grow and survive in diverse conditions. The influence of environmental factors on its growth and proliferation were evaluated. The yeast used for the study was isolated from honey using Sabouraud Dextrose Agar and pour plate methods. The effects of temperature, pH and ultraviolet radiation on the growth of Rhodotorula, Debaryomyces, Zygosaccharomyces and Candida species were determined using standard methods. The growths of all the yeast isolates were greatly affected at 80oC. Rhodotorulla species showed least growth at 50oC, but optimal growth was recorded at 30oC after 96 h of incubation. A similar trend was observed in Debaromyces species. Zygosaccharomyces species recorded high reduction in growth at 60oC after 96 h of incubation, though there were no significant differences in the growths of the isolates at 60oC and 80oC. Candida species recorded the least effect of temperature at 30oC and highest at 60oC and 80oC after 96 h of incubation. The results of the effect of pH on growth of the yeasts showed that Rhodotorula and Zygosaccharomyces had optimum growth at pH of 5 and 4 respectively. All the isolates showed increase in growth with increase in incubation time. Exposure of the isolates to UV-rays negatively affected the growths of the isolates. The growths of the yeasts decreased with increase in exposure time. This study showed that yeast can survive adverse temperature and pH and can as well survive UV-ray exposure
Role of the Epidemiologist in the Containment of COVID-19 Pandemic
The COVID-19 virus is a novel virus that is zoonotic and has infected more than two million people with over Three hundred people who died from the pandemic. The virus has been declared a pandemic by the W.H.O overwhelming the health system and capacity of many countries with known cases of death of health workers and non-health workers alike. The virus can be prevented through adequate personal and respiratory hygiene and maintaining social distancing at this point in time. Although doctors and nurses might be the frontline and visible image of health workers in the ongoing battle against the virus, there are other health workers behind the scene like epidemiologists working round the clock to control this current pandemic Epidemiologist deals with data and data is the focal point in the prevention and control of diseases. Epidemiologists are involved in the Surveillance, Identification and Monitoring of Outbreaks, conducting researches and evaluating policies geared at Outbreaks. Problems associated with Data are the major constraints of an Epidemiologist. Efforts are currently ongoing by various health personnel to control the virus and provide vaccines for the treatment of the disease
A sensitivity analysis of a gonorrhoea dynamics and control model
We formulate and analyse a robust mathematical model of the dynamics of
gonorrhoea incorporating passive immunity and control. Our results show that
the disease-free and endemic equilibria of the model are both locally and
globally asymptotically stable. A sensitivity analysis of the model shows that
the dynamics of the model is variable and dependent on waning rate, control
parameters and interaction of the latent and infected classes. In particular,
the lower the waning rate, the more the exponential decrease in the passive
immunity but the susceptible population increases to the equilibrium and wanes
asymptotically due to the presence of the control parameters and restricted
interaction of the latent and infected classes.Comment: Journal of Mathematical and Computational Science, 202
Comparison of preliminary results from Airborne Aster Simulator (AAS) with TIMS data
The Japanese Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), being developed for a NASA EOS-A satellite, will have 3 VNIR, 6 SWIR, and 5 TIR (8-12 micron) bands. An Airborne ASTER Simulator (AAS) was developed for Japan Resources Observation System Organization (JAROS) by the Geophysical Environmental Research Group (GER) Corp. to research surface temperature and emission features in the MWIR/TIR, to simulate ASTER's TIR bands, and to study further possibility of MWIR/TIR bands. ASTER Simulator has 1 VNIR, 3 MWIR (3-5 microns), and 20 (currently 24) TIR bands. Data was collected over 3 sites - Cuprite, Nevada; Long Valley/Mono Lake, California; and Death Valley, California - with simultaneous ground truth measurements. Preliminary data collected by AAS for Cuprite, Nevada is presented and AAS data is compared with Thermal Infrared Multispectral Scanner (TIMS) data