Vegetable growers perception of pesticide use practices, cost, and health effects in the tropical region of Cameroon

Pesticide use practices of vegetable farmers were investigated during surveys conducted in major vegetable production zones of the humid tropics of Cameroon. The surveys aimed to elucidate farmers’ crop calendar, pesticide spray schedule and frequency. Farmers’ knowledge was determined on pest targets, quantities and major active ingredients used, and training received in vegetable production. It was found that weekly spray of pesticides was the most common practice; 40% of farmers sprayed insecticide, 28% sprayed fungicides. However, 45 and 59% could not identify the insect pests and diseases respectively they were attempting to control. Farmers applied 0.5-9 liters of pesticide per year, 10-49 kg, and 10 to 49 packets of chemicals depending on farm size. Prices of pesticide range from 5000 to 13000 FCFA per liter of insecticide, 6000 to 8500 FCFA per kg of fungicide and 300 to 12000 F per packet. Ninety percent of farmers used a knapsack sprayer and 20% of farmers noticed that their health was affected by pesticides. About 25% of farmers store chemicals at home. Seventy-five percent receive information about agricultural production from other farmers, and have never received any training on pesticide use practices and health effects. The absence of farmer training further increases the danger of pesticide misuse and cost of vegetable production. Less expensive pest management options that are less hazardous to the environment and human health need to be introduced to farmers, and create awareness regarding hazards of mishandling pesticides if the products are to be used by vegetable farmers in Cameroon. Keywords: Pest and diseases, pest management, chemical spray.

Phytochemical and antioxidant analysis of wild and ex situ cultivated shoots and tubers of Harpagophytum procumbens (Burch) DC ex.Meisn from Botswana

Comparative phytochemical analysis [TLC method] and antioxidant activity of wild and  ex situ cultivated
shoots and tubers of  Harpagophytum procumbens were done. Total phenolic content [Folin-Ciocalteu
method] and free radical scavenging activity [1,1-diphenyl-2-picryl-hydrazyl assay] of both chloroform and
methanol extracts were determined. Analysis of ex situ cultivated plant material showed presence of phytochemicals comparable with those found in the wild plants. The total phenolic contents (mg GAE/L) of
methanolic tuber extracts from wild plants (3366±22.68) were comparable to the methanolic tuber extracts
(3297.00±54.56) from ex situ cultivated plants. The total phenolic contents of methanolic leaf extracts from
wild (2562±158.77) plants were also not significantly different from the  ex situ (2686.00±10.49) cultivated
H.procumbens. Similar trends were observed in the chloroform extracts of both wild and ex situ cultivated
H.procumbens. The free radical scavenging activities also correlated well with the total phenolic contents of
both wild and ex situ cultivated plants. At all tested concentrations, the methanolic extracts of both wild and
ex situ cultivated plants were ≥80%. The scavenging potencies of chloroform extracts were consistently
lower than the methanol extracts in both ex situ cultivated plants and wild species. The consistency in presence of phenolic compounds in these plant materials is of interest from both the pharmacological and conservation point of view given the role played by these compounds in oxidative stress. These results indicate
that ex situ cultivation can be both a conservation strategy and can provide an alternative and sustainable
source of therapeutically active compounds.

Agromorphological and Phenological Variability of 10 Bambara Groundnut [Vigna subterranea (L.) Verdc. (Fabaceae)] landraces cultivated in the Ivory Coast

The objective of this study was to investigate the agro-morphological and phenological characteristics often Bambara groundnut landraces that originated in the Ivory Coast. The study was conducted on an experimental plot at the University of Abobo-Adjame. The trial was set up according to a randomized complete block design with five replications. Twenty variables were used to identify the landraces. Landraces Ci1, Ci3, Ci10 and Ci12 exhibited high emergence percentages, early maturity within 90 DAS (days after sowing) and low vegetative/floral development. A high seed yield (388 to 495 kg/ha) was also obtained from these landraces. In contrast, a low seedling emergence rate, high vegetative development and yield (80 kg/ha) could be observed with landrace Ci9. This landrace reached maturity within 180 DAS. Landraces Ci2, Ci4, Ci5, and Ci8, on the other hand, reached maturity between 120-150 DAS. The principal component analysis conducted on the data obtained showed that the landraces with a high seed yield were early in terms of flowering and maturity, but presented low vegetative development, with limited foliage, secondary roots, leaf area and biomass. The physiological and agronomical traits presented by landraces that originated in the Ivory Coast could be exploited in Bambara groundnut varietal improvement programmes.

Cattle Productivity and Nutritional Limitation in the Semi-Arid Makgadikgadi Region of Botswana

Cattle growth and reproductive performance in the semi-arid Makgadikgadi region of Botswana was
investigated. Calving Rates (CR) and Growth Rates (GR) of Brahman beef cattle breed were used as
indicators of productivity and covered the periods of 2005-2009. Animal nutritional status involved
collection of faecal samples from rectums of 20 randomly selected cattle while the clipping method was
used to collect herbaceous samples from 1m
2
plots randomly located both in the Nata  ranch and
adjacent communal grazing areas. The herbaceous sampling period covered the wet season, late wet
season, dry season and late dry season. The mean calving rate for Brahman cattle in the study area was
relatively low (46.37 ± 3.45%). The  growth rate prior to weaning and post-weaning for both male and
female calves were poor compared to the national average productivity indicators. Faecal samples
indicated significantly low N levels (P<0 .05=".05" animal="animal" below="below" dry="dry" during="during" fell="fell" nbsp="nbsp" p="p" season="season" the="the" weight="weight" which="which">maintenance requirements, but peaked during the wet season. Faecal P significantly varied between
sampling periods, which was associated with rainfall distribution. The lowest faecal P was observed
during the late wet season whilst the highest amounts were observed during the late dry season.
Forage nutritive value (especially CP, P and Ca) varied significantly (P<0 .05=".05" nbsp="nbsp" p="p" seasons.="seasons." study="study" the="the" with="with">concluded that cattle performance in Makgadikgadi region could be limited by nutritional deficiency.
Thus, appropriate supplementation strategies can be developed to address mineral imbalances
observed especially during the dry seasons.

Essential and toxic metals in cow’s whole milk from selected sub-cities in Addis Ababa, Ethiopia

The level of essential (Fe and Zn) and non essential (Cd and Pb) metals in whole cow milk was
determined by Flame Atomic Absorption Spectrophotometer (FA-AAS).Whole cow milk was sampled (n
= 32) from dairy farms of Akaki-kality, Bole, Kolfe- keraniyo, and Yeka subcities in Addis Ababa.
Statistical analysis was performed using SPSS version 17. Significant differences between means were
subjected to one way ANOVA using Duncan’s multiple range test (P < 0.05). The average concentrations
of the elements were Fe (1.213±0.077 mg/kg), Zn (4.923±0.277 mg/kg), Cd (0.100±0.006 mg/kg) and Pb
(0.998±0.251 mg/kg). The levels of toxic metals (Cd and Pb) were beyond the acceptable limit which can
be a potential health concern for consumers.

Implications of Climate Change and Water Resources in Botswana

Climate variability (and /or change) continues to be recognized as the major threat to development of
the southern African region particularly in Botswana, where the major impact has been felt on the water
resources among others. This study, therefore attempts to analyze changes in key climatic variables
(rainfall and temperature) and their impacts on river flows. Mann-Kendal trend analysis was carried out
for four major meteorological stations (Gaborone, Gantsi, Francistown  and Maun). The results show
that  annual rainfall has been decreasing  while temperature  has been increasing, all insignificantly.
Through homogeneity tests, the study revealed that no country-wide statement can be made about
trend direction in  annual rainfall while for temperature a country-wide statement can be made that
temperatures are generally increasing. An attempt to study the linear relationships between rainfall and
river flows at Francistown and Gaborone revealed poor and insignificant correlations of 0.21 and 0.14
respectively. Projections of temperature and rainfall up to the year 2050 were undertaken through the
MAGICC/SCENGEN at which precipitation will decrease by 5% while temperature will increase by 2.5°C
with likely impacts of 7.9 and 4.4% reduction in river flows respectively. The findings have revealed that
rainfall and temperature have to be re-evaluated across the whole country with consideration of
modeling approaches that can handle non-linearity and complex inter-plays of other factors if water
resources management and planning are to be improved for semi-arid Botswana

Movement of Aphis craccivora (Koch) and Melanaphis sacchari (Zehntner) between Plants Provides Further Evidence on Prevalence of Apterous Dispersal among Aphids | Noga | Journal of Agricultural Science

A greenhouse study was conducted in the Botswana College of Agricultures’ greenhouse to determine the possible movement of two aphid species Aphis craccivora) (Koch), and Melanaphis sacchari (Zehntner), on cowpea and sorghum respectively. The aphid colonies of each species used were obtained from a greenhouse culture reared from progeny of single virginoparous apterous females. The plants were arranged such that one plant (the source plant) was put in the centre surrounded by four other plants (catch plants) so that the edges of the pots touched but without contact between the plants. In both experiments, each of the four groups of plants was kept on permanently moist irrigation matting in the greenhouse. The results showed that dispersal from initially colonized source plants occurred when plants appeared to be growing normally and when crowding was unlikely to be the cause. In both experiments this dispersal occurred when the population on the source plant exceeded about 10 adults and their offspring per plant. The implications of this behaviour are discussed, and it is argued that apterous dispersal may be common in aphids, allowing maximum utilization of the environment than would be likely by alate dispersal alone.

Effects of Moringa oleifera root and leaf powder on reproductive capacity and damage caused on stored cowpea seed by Callosobruchus maculatus

A laboratory study was conducted to investigate the effect of Moringa (Moringa oleifera) root and leaf powder on reproduction and damage to cowpea seed by Callosobruchus maculatus F at Botswana College of Agriculture in Gaborone, Botswana, in March 2012. Two experiments were conducted to test the effects of moringa leaf and root powder on C. maculatus using susceptible cowpea variety blackeye. The root powder was applied at dosages of 10%, 15%, 20%, 25%, and 30% of 8.00g seed while leaf powder was applied at 10%, 15%, 20%, 25%, 30%, 35% and 40% of 8.00g of seed. Malathion was included in both experiments as a check, applied at dosage of 0.01g per kg of seed. The results showed that moringa root powder significantly protected cowpea seed against damage by C. maculatus. We observed significant reduction in number of eggs laid, percentage of eggs hatched percentage of adult emerged, number of exit holes and seed weight loss when seeds were protected by moringa root powder.

Mixing seeds with leaf powder did not significantly affect the number of eggs laid, the number of hatched eggs, the number of adults emerged, the number of exit holes and percentage seed weight loss. It is therefore considered that based on the dosages used in this experiment, moringa leaf powder may not be effective in reducing seed damage by C. maculatus. In contrast, moringa root powder has potential to reduce damage by C. maculatus on stored cowpea seed.