African Journals Online
JOURNAL OF THE GHANA SCIENCE ASSOCIATION
VOLUME 3 No. 3 – 2001
Abstracts
Differential effects of insulin injections and insulin
infusions on levels of glycogen in rat adipose tissue
D.A. Antwi
Department of Physiology, University of Ghana Medical
School, P.O. Box 4236, Accra, Ghana.
ABSTRACT
Studies have shown that while injections of insulin cause an
increase in fat mass, infusions of insulin increase fat mass. The
aim of this paper was to test the hypothesis that if an increase
in glycogen is an indicator of an impending increase in adipose
mass, then insulin infusions should not increase glycogen, while
insulin injections should. Normal rats were treated with insulin
(or saline in control group) either by intraperitoneal injection
or by tail vein infusion. In agreement with previous evidence,
insulin injections increased glycogen in adipose tissue
significantly within 12 hours of injection. In contrast to
injections, insulin infusions failed to increase glycogen in rat
adipose tissue. This report concludes that adipose tissue
glycogen is a prelude to an increase in the size of adipose
tissue.
Theoretical consideration and evaluation of thermal
diffusivity characteristic coefficients of resin/ionomer
restorative biomaterials
George K. Toworfe1, David C. Watts2
1Department of Basic Dental Science,
University of Ghana Dental School,
P.O. Box KB 460, Korle-Bu, Accra.
2Biomaterials Science Unit, The
University of Manchester Dental School.
ABSTRACT
The aim of this study was to theoretically consider and
evaluate the transient temperature-time response of resin/ionomer
materials between ~2EC (melting ice temperature) and ~50EC, and
indicate their suitability as lining materials. Specimens of
materials, cylindrical in geometry, (6 mm diameter and 10 mm in
length), were fabricated with teflon moulds. These were subjected
to successive temperature-time transients, after allowing them to
equilibrate for 2 hours. A centrally embedded thermocouple, in
the cylindrical specimens, was then outputted to the data
acquisition system. The data capture per specimen of a material
was repeated 10 times. The appropriate theory related to the
solid of cylindrical geometry was developed and applied in
evaluating thermal diffusivity coefficients, A, of
materials from the heating and cooling thermal phases during the
experiment. Statistical analysis of the data obtained using
two-way ANOVA test, showed no marked differences (p < 1.00)
between the two thermal diffusivity data sets. Diffusivity
magnitudes of the resin/ionomer materials ranged between 0.14 and
0.30 mm2s-1 ,with Charisma, a conventional
composite, showing maximum thermal diffusivity of ~0.30 mm2/s,
and the least value of 0.15 mm2/s obtained by Compomer
F2000. The theory of thermal diffusivity as applied to
cylindrical-shaped materials has indicated the transient
temperature-time response to heat stimuli of dental restorative
biomaterials. Thermals diffusivities of the resin/ionomer
materials have also indicated their suitability as liners, as
such, the parameter remains a significant factor in the choice of
a lining material for restoration.
Observations on the reproductive biology and recruitment of
the bigeye grunt, Brachydeuterus auritus
(Pisces: Haemulidae), in Ghana
A. Asabere-Ameyaw
Department of Science Education, U.C.E.W., Winneba, Ghana
Current address: Department of Oceanography and Fisheries,
University of Ghana, Legon
ABSTRACT
Aspects of the reproductive biology and recruitment pattern of
the bigeye grunt, Brachydeuterus auritus (Valenciennes,
1831), are presented in this paper. Data were collected on
monthly samples obtained from the artisanal commercial fishery
occurring off Cape Coast, Ghana, between November 1993 and
October 1995. Both male and female B. auritus appeared to
be in better condition just before the minor upwelling
(January/February) in Ghanaian coastal waters. In the samples
collected, the females outnumbered the males. The length at first
maturity was observed as 10.1 cm for both sexes, a size that
corresponded to an age of 4 months. The length at massive
maturation (L50%) was, however, estimated
at 14.8 (= 9.1 months) and 15.1 cm (= 9.5 months), for the males
and females, respectively. The oocyte diameter distributions
suggested restricted spawning in the species. The occurrence of
ripe fish in all the samples, however, is an indication of
protracted spawning. Although individuals were ready for spawning
throughout the year they probably spawned during the upwelling
seasons. In the species, recruitment occurred throughout the
year, but with two pulses of unequal strength, with the major
recruitment occurring just before the upwelling periods.
Foot placement cues used by chameleons while walking and climbing
Edward Saiff1and Michael Vagell2
1Biology Program, Ramapo College, Mahwah,
New Jersey 07430, [email protected]
2Department of Psychology, Stanford
University, Stanford, California 94305-2130
[email protected]
ABSTRACT
Old world chameleons spend much time on branches of trees and
shrubs. We studied the cues used by chameleons in positioning
their feet while walking and climbing. Chameleons moving on
dowels of varying position and diameter were videotaped to
determine the sequence and location of each footfall. Visual
cliff experiments tested whether chameleons used visual or
tactile cues for limb placement. Visual cues appeared to provide
the primary sensory input for forelimb placement. Whenever vision
was impaired, the animal utilized touch. Placement of the
forelimb was the locator for the hind limb. Regardless of perch
diameter, the hind foot was placed fully or partially overlapping
the position that the ipsilateral forefoot had just occupied.
A preliminary survey of the ecto and endoparasites of the
grasscutter (thryonomys swinderianus
temminck): case study in Ekumfi, Cental region of Ghana
S. Yeboah and P.K. Simpson
Department of Zoology, University of Cape Coast, Cape
Coast.
ABSTRACT
Domestication and farming of grasscutter is gradually
spreading throughout the country as an important source of
protein to supplement grasscutter meat obtained from the wild,
yet very little is known about their diseases. The present study
attempts to throw some light on parasitic infestations capable of
hindering grasscutter farming in Ghana. One hundred and fifty
grasscutters (or cane rats) were examined within a period of
seven months for ecto and endoparasites at Eisam in the Ekumfi
District of Ghana. Four species of ticks namely: Rhipicephalus
simpsoni, Ixodes aulacodi, Ixodes sp. and Hemaphysalis
parmata were the ectoparasites found. The ticks were
found on all body regions of the grasscutters. The anterior part
of the body was found to have the highest tick infestation,
whilst the posterior had the least. The probable season for site
preference has been discussed. Six species of helminth parasites
comprising 2 species of cestodes and 4 species of nematodes were
found in various parts of the gut of the grasscutters. The
cestodes were Furhmanella transvaalensis, Railettina mahonae
and the nematodes were Longistriata spira, Trachypharynx
natalensis, Paralibyostrongylus vondwei and Trichuris
paravispicularis. This is the first report of R. mahonae
as a parasite in the gut of the grasscutter. There was no
significant difference in relative infestation between male and
female grasscutters for any tick or helminth species. We hope
that this study will encourage further research into other agents
of grasscutter diseases to reduce mortality and thereby help to
increase grasscutter meat production in the country.
Nutritional quality of selected Ghanaian crab species
W. Oduro1, W.O. Ellis2,
I. Oduro2 and D. Tetteh1
1Institute of Renewable Natural
Resources, KNUST, Kumasi, Ghana.
2Biochemistry Department, KNUST, Kumasi,
Ghana.
ABSTRACT
Crabs form a substantial proportion of the diet of the
Ghanaian populace. However, effective management of this food
resource is lacking, due to paucity of data on the food value of
these species. Studies were carried out to determine the
nutritional quality of three commonly consumed crab species, the
African ghost crab, the bigfisted swimcrab and the lagoonland
crab. Parameters monitored were moisture, fat, protein, fibre,
ash and mineral levels. The results showed that crab species have
high ash (23.68 – 58.35%) and mineral content (Na, 324
– 1006.76mg/100g; K, 265.62 – 1006.25mg/100g and P,
33.47 – 803.35mg/100g). The bigfisted swimcrab and the
lagoonland crab have appreciable levels of protein (4.59% and
4.46%, respectively). However, the African ghostcrab had low
protein content. All the three species contain substantial levels
of crude fibre. The results also showed that different portions
of the crab contribute varying amounts of nutrients to the diet.
Characterization of sweet potato starch – the effect of cultivation time
S. Yempew,1 W.O. Ellis,1*
I. Oduro,1 and N.T. Dziedzoave2
1Department of Biochemistry, Kwame
Nkrumah University of Science & Technology, Kumasi, Ghana.
2Food Research Institute (CSIR), P.O. Box
M20, Accra, Ghana.
ABSTRACT
The physicochemical properties of the starches of seven sweet
potato varieties at two harvesting times were studied. The yield
of starch, pH, moisture, Water Binding Capacity (WBC),
solubility, swelling volume, swelling power, ash and viscosity
were monitored. Starch from the 4 month varieties had higher
yields (12.78-18.72%), moisture contents (7.82-15.04%) and pH
levels (3.59-5.22) relative to that from the 5-month varieties.
The starch from the 5-month varieties, however, had higher WBC
(66.30-76.90%) and viscosity at 73EC (18.80-35.60 cps) and 35EC
(27.20-53.40 cps). With respect to swelling behaviour, the
4-month samples were of good quality having low solubility and
high swelling volume. The findings thus show that cultivation
time and variety impact on the physicochemical properties of
starch from sweet potato roots.
Incidence of natural enemies of planococcoides
njalensis Laing and planococcus citri Risso in
researcher-managed and farmer-managed cocoa farms
Joseph B. Ackonor
Cocoa Research Institute of Ghana, P.O. Box 8, New
Tafo-Akim, Ghana
ABSTRACT
Studies were carried out at Tafo in researcher (CRIG)-managed
farms and farmer-managed farms to assess the incidence of natural
enemies in colonies of Planococcoides njalensis Laing and Planococcus
citri Risso, the two most important vectors of the Cocoa
Swollen Shoot Virus disease in Ghana. The CRIG farms were sprayed
four times with either lindane or propoxur per mirid season,
using motorised knapsack sprayers, and weeded at least twice
annually, mostly by slashing with cutlass and occasionally by
applying herbicides. Control of black pod disease caused by Phytophthora
palmivora (Butl.) Butl. was by a combination of cultural
practices and chemical control. The peasant farmers partially
adopted the CRIG recommendations, spraying unspecified dosages of
any available insecticides once or twice annually against mirids,
and rarely spraying against the black pod disease. Most weeded
once or twice annually while others waited till harvesting time,
only to make tracks to trees carrying ripped pods. Mealybug
colonies were sampled monthly in both farm types by examining
cocoa trees from the base to hand height, brushing observed
colonies within this range into glass vials and taking them to
the laboratory. Unparasitized adults (females), third instar
nymphs and mummies were separated and counted to give an estimate
of the colony size. Mummies were kept in vials and observed for
the emergence of parasitoids. The monthly incidence of both P.
njalensis and P. citri colonies on the farmers' farms
and the CRIG farms did not differ significantly. Similarly, the
percentages of their colonies free from natural enemies in
the two farm types did not differ significantly, and the
differences in the incidence of parasitoids, and also of
predators, in colonies of the two vectors in the two farm types
were not significant. These results are discussed in terms of
agrochemical usage and the efficiency of the natural enemies in
the control of mealybug vectors of CSSV.
The influence of background model parameters on the
accuracy of X-ray intensity evaluation using the AXIL software
F.G. Ofosu1, S. Akoto Bamford1,
I.J. Kwame Aboh1 and G.K. Tetteh2
1Physics Department, National Nuclear
Research Institute,
Ghana Atomic Energy Commission, Kwabenya.
2Department of Physics, University of
Ghana, Legon.
ABSTRACT
Quantitative procedures in Energy-Dispersive X-ray
fluorescence (EDXRF) analysis require the conversion of measured
X -ray intensities into elemental concentration. Some softwares
have been developed for the deconvolution of X-ray spectra, and
AXIL is one of such computer programmes. AXIL provides a number
of background models that can be used for X-ray intensity
evaluation. The choice of the order of the polynomial for the
linear and exponential background models and the number of
iterations for the smooth filter background model in spectra
fitting with the AXIL programme version 3.1 has been investigated
using a Cd-109 radioisotope source and a Si(Li) detector. This
was carried out by determining the concentration of Ca in CaO, Zn
in ZnO, As in As2O3 and Co in its powdered
form, using all the possible orders of the polynomial/number of
iterations in the three background models. The results showed
that the choice of linear model for both sensitivity calibration
and sample analysis produces the best results. In all cases the
optimum number of parameters for the polynomial/ number of
iterations were found to give linear <= 4, exponential <= 4
and smooth filter <= 100.
Cocoa pulp juice (sweatings) as a potential raw material
for the development of soft drink
Esther Gyedu
Cocoa Research Institute of Ghana, Akim-Tafo.
ABSTRACT
Cocoa sweatings is a very interesting by-product of cocoa
production and it forms the substrate for microbial growth during
the fermentation process. Most of the sweatings go to waste
during the processing of the cocoa beans and this has led to its
utilization as a potential raw material for the development of
soft drink to enhance the importance of cocoa as a source of
income for farmers. A natural, shelf stable, ready-to-serve fruit
drink was prepared using cocoa sweatings, sugar and water. 1000
ppm sulphite was added to the juice, pasteurized at 90EC, then
transferred to presterilized bottles, corked and pasteurized
again for 30 minutes and assessed organoleptically for flavour,
colour and overall acceptability. Titratable acidity, pH and
turbidity were measured on each experimental product. Regression
analysis was used to fit a linear relation to the data of all
dependent sensory and physico-chemical variables evaluated.
Correlation was also used to find the effect of sensory and
physical variables on acceptability. Increasing sweating
proportion increased all the sensory and physico-chemical
variables. Sweetness was high at 0.10 level of sugar and reduced
as the amount of sugar added decreased. Sweetness highly
correlated with acceptability ( r = 0.99). The quality was still
good after 3 months with no microbial growth. Sodium
metabisulphite added to the processed juice drinks enhanced the
thermal inactivation of microorganisms.
Population dynamics of prostephanus truncatus
(horn) and sitophilus zeamais
motschulsky in a traditional barn: the influence of maize variety
and season
B.A. Boateng1, J.N. Ayertey1
and W.G. Meikle2
1Department of Crop Science, P.O. Box
LG44, University of Ghana, Legon
2European Biological Control Laboratory,
USDA-Agricultural Research Service, Campus International de
Baillarguet, CS 90013 Montferrier sur Lez, 34988 St. Gely du Fesc
CEDEX, France.
ABSTRACT
The effects of three maize varieties and two storage seasons
on the population dynamics of Prostephanus truncates
(Horn) and Sitophilus zeamais Motschulsky were observed in
the traditional `Ewe' barn in the field. Two local varieties,
Dzolokpuita and Abutia and an improved variety, Abeleehi, were
stored with the husk on, during the long season, and Abutia only
during the short season of the 1994/1995 storage period.
Destructive sampling techniques were applied to obtain data at
monthly intervals for eight months. Maize variety significantly
influenced P. truncatus density (p < 0.05) during the
storage period. However, it did not influence the population
dynamics of S. zeamais. Trend analysis showed significant
increase in densities of P. truncatus over time,
especially during the late phase of the long season with maximum
densities of 131.1, 43.7, and 16.9 adults per kg grain for
Abutia, Abeleehi and Dzolokpuita, respectively. S. zeamais
density, however, peaked at between 280 and 350 adults per kg
grain on all varieties after only three months of storage, then
stabilized at about 250 insects per kg grain for the rest of the
season. Maize variety also influenced weight loss with
Dzolokpuita faring better. Good husk cover and relatively harder
grains of Dzolokpuita may explain the lower P. truncatus
density and weight loss recorded for this variety. Season did not
affect P. truncatus density, but it influenced S.
zeamais dynamics and weight loss levels.
Managing infestation levels of major insect pests of garden
eggs (solanum integrifolium L.) with aqueous neem
seed extracts
F. Owusu-Ansah1, K. Afreh-Nuamah2,
D. Obeng-Ofori3, K.G. Ofosu-Budu4
1African Regional Postgraduate programme
in Insect Science (ARPPIS),
Zoology Department, University of Ghana, Legon.
2 & 4Agricultural Research Station
(ARS-Kade), Faculty of Agriculture, University of Ghana.
3Crop Science Department, Faculty of
Agriculture, University of Ghana, Legon.
ABSTRACT
Performance of Aqueous Neem Seed Extract (ANSE) at 75 g/L of
water (22.5 kg/ha) was evaluated on Legon I variety of local
garden egg in the field. The effect of ANSE was compared with a
registered Bacillus thuringiensis Berl. (Biobit), a
synthetic insecticide (Karate 2.5 EC) and an untreated control
(water only). Karate and Biobit were applied at rate of 2.5 ml/L
(800 ml/ha) and 0.8 g/L (0.24 kg/ha), respectively. The effect of
each treatment on insect abundance, defoliators, shoot, bud and
fruit borers were determined. Water traps were used to monitor
the effect of the three products on the abundance of insect fauna
associated with crop. Insects from seven major orders
(Coleoptera, Lepidoptera, Odonata, Orthoptera, Diptera, Hemiptera
and Hymenoptera) were found associated with the local garden egg.
The major insect pests of the crop included the shoot and fruit
borer, Leucinodes orbonalis (Guen.), which attacked the
shoots and fruits, the bud borer (budworm) Scrobipalpa
blapsigona (Meyrick), which oviposited into the buds
and the feeding activities of the larvae, led to the abortion of
buds, Pachnoda cordata (Drury) which scraped and
chewed stem and shoot and defoliators comprising Acraea
peneleos peneleos (Ward.), Acraea pharsalus pharsalus (Ward.),
Zonocerus variegatus L., Eulioptera sp., Urentius
hystericellus (Richter) and Phaneroptera nana (Stal.).
Karate and ANSE significantly (p < 0.05) reduced population
levels of some major pests such as P. cordata and Z.
variegatus than Biobit. The mean number of L. orbonalis
and S. blapsigona in the shoots and buds, respectively
were significantly higher (p > 0.05) on plots treated with
ANSE and Biobit than Karate. This suggests that neem seed extract
and Biobit had little or no systemic action against shoot and bud
borers of the crop in the field. Significantly fewer (p <
0.05) numbers of predators mainly ants and ladybird beetles were
collected from plants treated with Karate compared to either
ANSE- or Biobit- treated plots. This indicates that Karate had
adverse effects on beneficial insects in the garden egg
ecosystem. Karate and ANSE also significantly (p < 0.05)
reduced percentage fruit damage, number of borers per fruit and
the activities of leaf feeders. Although ANSE could not
effectively control the shoot and bud borers as Karate, it
performed better in reducing borer damage than either Biobit or
control. With proper timing and innovative methods of
application, aqueous neem seed extract can be used as alternative
or supplement to synthetic insecticide for the management of
vegetable pests of local garden eggs by resource poor farmers.
Artisanal and modern processing of palm oil in Ghana
N.K. Mensah and G.S. Ayernor
Department of Nutrition and Food Science, University of
Ghana, Legon.
ABSTRACT
Traditional palm oil processing methods and modern industrial
processes are both contributing to the production of palm oil for
food and other uses in Ghana. This study examined the processes
of a traditional method (Bedo) and a modern technological
process (TOPP) and compared the quality indices of the products
of the two processes. Samples of oil at the various stages of the
processes were taken and analysed for critical quality indices to
compare the quality and stability of the oils. Results showed
that the modern industrial process produced significantly (p =
0.05) better quality palm oil than the artisanal method,
especially with regard to moisture content and susceptibility to
oxidation.
Characteristics of malted rice for the production of sugar
syrup
T.K. Hammond and G.S. Ayernor
Department of Nutrition and Food Science, University of
Ghana, Legon.
ABSTRACT
Studies were conducted on malted rice in an attempt to produce
rice malt with high diastatic power for the production of sugar
syrup from cassava flour. Rice malt was prepared by malting paddy
rice over 12 days at 28EC ± 2EC in the dark. The germination
power of the rice was studied and diastatic power in malted rice
determined. Relationship among diastatic power, malting period
and parts of malted seedling were studied. Results indicated that
the optimum diastatic power in rice malt occurred on the 10th
day of malting. Statistical analysis indicated a positive
correlation (r = +0.88) between diastatic power in rice-malt
seeds and seedling development to a point. Wet rice-malt with
plumule and radicle had the highest diastatic power of 91.50
degree lintner (EL) compared to rice-malt prepared from malted
rice seeds alone which had 65.67EL and dried malted rice seeds
with plumule and radicle which had 58.95EL. Malting rice for 10
days and preparing malt from germinated rice seeds with plumule
and radicle could give rice-malt with a high diastatic power for
the hydrolysis of starch in the production of sugar syrup.
Land-based sources of pollution and environmental quality of Weija lake
O.D. Ansa-Asare
Water Research Institute, Box 38, Achimota, Ghana
ABSTRACT
A survey of land-based sources of pollution was undertaken in
the catchment area of Weija Lake. Activities that may influence
the quality of the environment, and the sources, amounts and
effects of the pollution of the water body were assessed. Water
and precipitation chemistry showed that Na:Ca (0.48) and Na:K
(2.0) ratios were influenced by individual pollution and
terrestrial dust. However, Na:Cl (0.74) and Na:Mg (1.06) ratios
suggest an oceanic origin of these ions. Mean phosphate load of
100.4 t yr-1 for Weija Lake was enough for
eutrophication to take place. There was an input of 12.42 t yr-1
from settlements, and 9.072 t yr-1 from fertilizer
input through runoff, and then the Densu River also had an input
of 1,217.6 t yr-1 into the Weija Lake. Similarly, the
sources of pollution from settlements, runoff from fertilizer
input from the River Densu revealed that the major contributor of
nutrients and BOD into the Weija Lake is the River Densu. This
can be attributed mainly to the dumping of garbage, solid and
liquid wastes upstream of the River Densu. The high mean nitrogen
load of 3,003 t yr-1 can also be attributed to organic
nitrogen input from domestic and agricultural origin. This was
due to the high seasonal trend of nitrate in the months of March
and May as a result of the main ploughing periods for farming in
the Weija Lake catchment area, where fertilizer is applied.
Preliminary recommendations and remedial measures to solve the
problems as assessed, and proposed for preventive remedial and/or
control measures were made.
Off-host survival and reproductive success of adult female
winter ticks, dermacentor albipictus in
seven habitat types of Central Alberta
O.I. Aalangdong1, W.M. Samuel, and
A.W. Shostak
Department of Biological Sciences, University of Alberta,
Edmonton, Alberta, Canada T6G 2E9
1Department of Renewable Natural
Resources, University for Development,
P.O. Box 1350, Tamale, Ghana.
ABSTRACT
Winter tick is an important pest of moose which affects the
physical and physiological well-being of moose. All moose in
Alberta become infested with winter ticks every year and suffer
morbidity and mortality from the infestation. The ticks are
acquired in autumn in the habitats of EINP during search for food
and other ecological needs. When blood-engorged female winter
ticks, Dermacentor albipictus, drop from moose in
March-April, they have little choice in where to oviposit,
because their dispersal is minimal. The habitat in which they
drop is the habitat in which they must survive and produce
offspring. Different habitats with different microclimatic
conditions influence survival and reproduction of winter ticks
differently. Off-host survival and reproductive success of adult
female winter ticks were determined in 7 habitat types of Elk
Island National Park, Central Alberta, 1992. Adult ticks, in
gauze bags, were placed at ground surface in late April and
monitored for survival, egg-laying and larval survival to
November. Generally, more ticks survived to produce eggs that
hatched to larvae and the larvae survived longer, in habitat
types with open canopies (rank in order: upland shrub, grassland,
open aspen), where ground-litter temperatures in summer were
higher, than in habitat types with closed canopies (labrador tea,
spruce forest, willow shrubland). Results may explain why moose, Alces
alces, in Alberta that live in areas with open canopies
(i.e., aspen parkland and southern fringe boreal forest) appear
to suffer more from winter ticks than moose living in
spruce-dominated boreal mixed wood forests. Moose in these areas
probably acquire more ticks.
The use of biopesticides to control insect pests of papaya
(Carica papaya)
Alfred Akakpo, D. Obeng-Ofori and David Wilson
Insect Science programme (ARPPIS), University of Ghana,
Legon.
ABSTRACT
Laboratory and field experiments were carried out between June
1997 and January 1999 at Paradise farm near Nsawam in the Eastern
Region of Ghana to evaluate the effectiveness of neem seed
extract and Bacillus thuringiensis (Kurtaski) for
controlling insect pests of papaya Carica papaya. Methanol
and aqueous neem seed extracts were tested at the following
concentrations 0, 50, 75 and 100 g/L. Bacillus thuringiensis
was applied at the rate of 0, 0.2, 0.4, 0.6, 0.8 and 1.0 g/L.
Percentage mortality and leaf damage caused by insect pests were
determined in the laboratory and in the field. The population of
the major insect pests, which visited the plants, was also
determined. The nature of the damage caused by the insect pests
found on the various developmental stages of the plants was
assessed by critical visual observation. The major insect pests
recorded on papaya at Paradise farm were the variegated
grasshopper, Zonocerus variegates (L), mealybugs, Planococcus
sp and Mexican bean beetle, Epilachna sp. It
was observed in the field that the populations of these insect
pests were significantly reduced by the higher doses of methanol
and aqueous neem extracts as well as the Bacillus
thuringiensis treatments. The neem seed extracts and Bacillus
thuringiensis preparations had significant effect on the
mortality of adult and nymphs of Z. variegatus in the
laboratory and in the field compared to the control. The rate of
mortality increased as the dose increases. Hundred grams per
litre of methanol and aqueous neem seed extract and 1 g of B.
thuringiensis per litre of water were the most effective and
induced the highest mortality of adults and nymphs of Z.
variegatus compared to the other treatments. The least
percentage leaf damage was recorded on papaya plants treated with
the highest dosage of neem extract and B. thuringiensis.
Assessment of air, water and landbased sources of pollution
to the coastal zone of the Accra-Tema metropolitan area
R. Asmah and C.A. Biney
CSIR/Water Research Institute, P.O. Box M. 32, Accra.
ABSTRACT
A quantitative assessment of air, water and land-based sources
of pollution to the coastal zone of the Accra-Tema Metropolitan
Area of Ghana was conducted by making an emission inventory from
information on industrial, commercial and domestic activities.
Three sources of air pollution were analysed, viz, emission from
mobile combustion engine sources, stationary combustion sources
and industrial processes. The mobile combustion sources were the
largest contributors to air pollution. Concerning water
pollution, 15 industrial types were investigated. The Food and
Beverage industry accounted for more than 80% of the total waste
volume discharged per annum. The major rivers collectively
contributed more water pollution loads to the coastal zone than
the industrial effects. They, however, have less negative effect.
Solid waste loads, mainly in the form of dry solids and sludge,
from 16 industrial types, commercial and domestic sources were
computed. Commercial and domestic activities accounted for more
than 50% of the solid waste load discharged per annum. About 40%
of waste sludge is discharged into drains; some are incinerated,
while others are disposed off by land filling.
Growth promoting properties and yield effects of aqueous
neem seed extract, biobit and karate on local garden eggs
(Solanum integrifolium l.)
in the field
F. Owusu-Ansahl , K.
Afreh-Nuamah2, D. Obeng-Ofori3,
K.G. Ofosu-Budu2
1African regional postgraduate program in
insect science (ARPPIS), Zoology Department, University of Ghana, Legon.
2Agricultural Research Station (ARS),
Faculty of Agriculture, University of Ghana, Kade.
3Crop Science Department, Faculty of
Agriculture, University of Ghana, Legon.
ABSTRACT
Field experiments were conducted at Ekoso in the Eastern
Region of Ghana, to investigate the effect of Aqueous Neem Seed
Extract (ANSE) on vegetative growth and yield of the local garden
eggs Solanum integlifolium L. The extract was applied at
the rate of 75 g of seed powder per liter of water (22.5 kg / ha)
and compared with a standard insecticide, Karate (2.5 EC) and
registered Bacillus thuringiensis Berl. (Biobit)
preparations applied at 2.5 ml/L (800 ml/ha) and 0.8 g/L (0.24
kg/ha), respectively. The effects of the treatments on whole
plant biomass, flower production, number of major branches,
number of functional leaves, plant height, plant girth, number of
fruits per plant, fruit weight and yield were determined. The
ANSE at 75 g/L significantly (p < 0.05) promoted vegetative
growth than the other treatments, but delayed flower initiation.
Karate and Biobit, however, had no significant (p > 0.05)
influence on vegetative growth of the crop. Fruit yield per plant
differed significantly (p < 0.05) among the treatments. All
the three products produced higher yields than the control plots
with the Karate treated plants producing significantly (p <
0.05) the highest fruit yield. Plants treated with neem seed
extract produced higher fruit yield, fruit weight and flower
production than those sprayed with Biobit although the difference
was not significant.
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