54 research outputs found
Farmers perception of problems in the cultivation of selected leaf vegetables in South Western Nigeria
The development of alternative strategies for sustainable pests’ management in vegetable production (using insecticides of plant origin) is particularly important in a country like Nigeria where synthetic insecticides are not readily available and farmer s are poorly equipped to handle them. This research was conducted to unravel farmers’ perception of insect pest activities as a constraint to vegetable production and to ascertain the most important pests and indigenous methods of control (using plant extracts). Baseline surveys were conducted using well structured questionnaire on farmers’ plots in farming communities of Akure North and South Local Government Areas of Ondo State. Results from the study affirmed, that all the farmers had the problem of pests on their farms. They have ranked Podagrica sjostedti, P. uniforma, Sylepta derogata, Dsydercus superstitiosus, and Zonocerous variegata as the most important insect pests of the selected leaf vegetables: Amaranthus hybridus, Celosia argentea, and Corchorus olitorius. The results further indicated that 76% of the farmers were aware of the use of indigenous methods of control (using different plant extracts) for the control of pests. The study showed that there was no significant association between education and the use of plant extracts. However, age, sex, and farming experience influenced the use of the plant extracts for insect pest control on the respondents’ farm
Insecticidal Evaluation of Bridelia Micrantha and Dalbergia Lactea Aqueous Extracts for the Control of Podagrica Uniforma (Jacoby) and Nisotra Dilecta (Jacoby) (Coleoptera: Chysomelidae) Infestation on Okra
Insect pest infestation is a major factor militating against okra production and farmers generally adopt synthetic insecticides for its management. A field trial was undertaken to evaluate the insecticidal potency of Bridelia micrantha and Dalbergia lactea for the management of Podagrica uniforma (Jacoby) and Nisotra dilecta (Jacoby) insect pest of okra (Abelmoschus esculentus L. Moench). The treatments consisted of aqueous leaf extracts of Bridelia micrantha and Dalbergia lactea and Cypermethrin as check; laid out in Randomized Complete Block Design and repli-cated three times. Data was collected on insect population before treatment application and 3 days after spraying of insecticides at 28, 35, 42, 56 days after planting (DAP). Yield parameters data collected were number of fruits and fruit weight. Results obtained showed that the plant extracts exhibited effectiveness in reducing the insect population and improved okra fruit yield compared to Cypermethrin. The order of effectiveness in decreasing sequence was found to be Cypermethrin ˃ D. lacteal ˃ B. micrantha. D. lacteal and B. micrantha crude extracts could be explored as promising insecticidal agents to provide valuable alternatives to chemical control of insect infestation on okra. Further study is recommended to determine the chemical constituents responsible for the plant insecticidal activity
Magnetic resonance imaging sequence evaluation of an MR Linac system; early clinical experience.
Objectives:To systematically identify the preferred magnetic resonance imaging (MRI) sequences following volunteer imaging on a 1.5 Tesla (T) MR-Linear Accelerator (MR Linac) for future protocol development. Methods:Non-patient volunteers were recruited to a Research and Ethics committee approved prospective MR-only imaging study on a 1.5T MR Linac system. Volunteers attended 1-3 imaging sessions that included a combination of mDixon, T1w, T2w sequences using 2-dimensional (2D) and 3-dimensional (3D) acquisitions. Each sequence was acquired over 2-7 minutes and reviewed by a panel of 3 observers to evaluate image quality using a visual grading analysis based on a 4-point Likert scale. Sequences were acquired and modified iteratively until deemed fit for purpose (online image matching or re-planning) and all observers agreed they were suitable in 3 volunteers. Results:26 volunteers underwent 31 imaging sessions of six general anatomical regions. Images were acquired in one or two of six general anatomical regions: male pelvis (n = 9), female pelvis (n = 4), chestwall/breast (n = 5), lung/oesophagus (n = 5), abdomen (n = 3) and head and neck (n = 5). Images were acquired using a pre-defined exam-card that on average, included six sequences (range 2-10), with a maximum scan time of approximately one hour. The majority of observers preferred T2-weighted sequences. The thorax teams were the only groups to prefer T1-weighted imaging. Conclusions:An iterative process identified sequence agreement in all anatomical regions. These sequences will now be evaluated in patient volunteers. Advances in knowledge:This manuscript is the first publication sharing the results of the first systematic selection of MRI sequences for use in on-board MRI-guided radiotherapy by end-users (therapeutic radiographers and clinical oncologists) in healthy volunteers
Growth status and menarcheal age among adolescent school girls in Wannune, Benue State, Nigeria
<p>Abstract</p> <p>Background</p> <p>Menarcheal age is a sensitive indicator of environmental conditions during childhood. The aim of study is to determine the age at menarche and growth status in adolescents in a rural area of Tarka, Wannune, Nigeria.</p> <p>Methods</p> <p>Data on 722 female students (aged 12-18 years) were collected in February 2009. Height and weight were measured. Body mass index (BMI; kg m<sup>-2</sup>) was used as an index of relative weight.</p> <p>Results</p> <p>Mean and median menarcheal age calculated by probit analysis were 13.02 (SD 3.0) (95% CI: 13.02-13.07), and age 13.00 (SD 2.8) (95% CI: 12.98-13.04), respectively. Girls who reach menarche are significantly heavier and taller with higher BMIs than those of their pre-menarcheal peers.</p> <p>Conclusion</p> <p>The age of menarche is probably still declining in Nigeria. Although BMI is an important factor in the onset of menstruation, some other unmeasured environmental variables may be implicated in this population.</p
Local Competition Between Foraging Relatives: Growth and Survival of Bruchid Beetle Larvae
Kin selection theory states that when resources are limited and all else is equal, individuals will direct competition away from kin. However, when competition between relatives is completely local, as is the case in granivorous insects whose larval stages spend their lives within a single seed, this can reduce or even negate the kin-selected benefits. Instead, an increase in competition may have the same detrimental effects on individuals that forage with kin as those that forage with non-kin. In a factorial experiment we assessed the effects of relatedness and competition over food on the survival and on fitness-related traits of the bruchid beetle Callosobruchus maculatus. Relatedness of competitors did not affect the survival of larvae. Larval survival substantially decreased with increasing larval density, and we found evidence that beetles maturing at a larger size were more adversely affected by competition, resulting in lower survival rates. Furthermore, females showed a reduction in their growth rate with increasing larval density, emerging smaller after the same development time. Males increased their growth rate, emerging earlier but at a similar size when food was more limited. Our results add to the growing number of studies that fail to show a relationship between relatedness and a reduction in competition between relatives in closed systems, and emphasize the importance of the scale at which competition between relatives occurs
Dietary intake patterns and nutritional status of women of reproductive age in Nepal: findings from a health survey
An assessment of the risk of Bt-cowpea to non-target organisms in West Africa
Cowpea (Vigna unguiculata Walp.) is the most economically important legume crop in arid regions of sub-Saharan Africa. Cowpea is grown primarily by subsistence farmers who consume the leaves, pods and grain on farm or sell grain in local markets. Processed cowpea foods such as akara (a deep-fat fried fritter) are popular in the rapidly expanding urban areas. Demand far exceeds production due, in part, to a variety of insect pests including, in particular, the lepidopteran legume pod borer (LPB) Maruca vitrata. Genetically engineered Bt-cowpea, based on cry1Ab (Event 709) and cry2Ab transgenes, is being developed for use in sub-Saharan Africa to address losses from the LBP. Before environmental release of transgenic cowpeas, the Bt Cry proteins they express need to be assessed for potential effects on non-target organisms, particularly arthropods. Presented here is an assessment of the potential effects of those Cry proteins expressed in cowpea for control of LPB. Based on the history of safe use of Bt proteins, as well as the fauna associated with cultivated and wild cowpea in sub-Saharan Africa results indicate negligible effects on non-target organisms
Effect of larval infestation on the choice of seed for oviposition by Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)
Toxicidad fumigante para Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae) de bulbos trozados de especies Allium.
Fumigant toxicity of crushed fresh bulbs of Allium sativum L. and A.
cepa L. to the Callosobruchus maculatus (Fabricius), a major pest of
stored cowpea (Vigna unguiculata (L.) Walp.) seeds was assessed under
laboratory conditions in Akure, Nigeria. In the tests, 20 g of infested
cowpea seeds were suspended in a piece of muslin cloth, over an amount
of crushed bulb in a container with a tightly fitted lid. Adult
emergence was completely prevented from freshly laid eggs of C.
maculatus on cowpea seeds that was fumigated with 6.0 g or more of
crushed bulbs of A. sativum. Such fumigated seeds were not holed at
all. Other amounts of A. sativum tested (1.0, 2.0, 3.0, 4.0 and 5.0 g)
significantly reduced C. maculatus adult emergence from fumigated eggs
and seed holing in comparison with the control. Crushed A. sativum was
ineffective in preventing adult emergence from fumigated C. maculatus
larvae in seeds. The fumigant effect of crushed A. cepa did not kill
all C. maculatus eggs. An amount of 7.0 g significantly reduced C.
maculatus adult emergence from fumigated eggs and seed holing in
comparison with the control. There is good prospect in using crushed
bulbs of A. sativum as fumigant in C. maculatus control in stored
cowpea seeds.Se evaluó la toxicidad fumigante de bulbos frescos trozados de
Allium sativum L. y A. cepa L. sobre Callosobruchus maculatus
(Fabricius), una importante plaga de semilla almacenada de caupÃ
Vigna unguiculata (L.) Walp. bajo condiciones de laboratorio en Akure,
Nigeria. En las pruebas, 20 g de semillas infestadas se suspendieron en
un trozo de tela sobre cierta cantidad de bulbos trozados en un
contenedor con una tapa ajustada. Se previno completamente la
emergencia de adultos desde huevos recién puestos de C. maculatus
en semillas de caupà que se fumigaron con 6,0 g o más de
bulbos de A. sativum. Estas semillas fumigadas no estaban ahuecadas.
Otras cantidades de A. sativum probadas (1.0, 2.0, 3.0, 4.0 y 5.0 g)
redujeron significativamente la emergencia de adultos de C. maculatus
desde huevos fumigados y el perforamiento de la semilla en
comparación con el control. A. sativum trozado fue inefectivo en
la prevención de emergencia de adultos desde larvas fumigadas de
C. maculatus en semillas. El efecto fumigante A. cepa trozada no
mató los huevos de C. maculatus. Una cantidad de 7,0 g redujo
significativamente la emergencia de C. maculatus adultos desde huevos
fumigados y el perforamiento de semilla en comparación con el
control. Los bulbos trozados de A. sativum se presentan como una buena
alternativa como fumigante en el control de C. maculatus en semillas
almacenadas de caupÃ
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