scholarly journals Cypress (Cupressus macrocarpa) Leaf Powder Modulates Metabolism of Maize Weevil Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Author(s):  
Tange Denis Achiri ◽  
Eta Carine Agbor ◽  
Ateh Marie Anye ◽  
Assan N. Abdulai ◽  
Divine Nsobinenyui ◽  
...  

Aims: Maize grains are severely damaged by maize weevil Sitophilus zeamais. Exploiting botanicals against synthetic insecticides as a control strategy has gained prominence in recent decades. The aim of the study was to investigate the potential of cypress (Cupressus macrocarpa) to exert some control on S. zeamais. Methodology: Maize and S. zeamais were collected from Muea market in Buea, Cameroon. The maize was heat sterilized and all debris removed. Sitophilus zeamais was reared for three generations before use. Ten S. zeamais were stored with 100 g of maize and 0 g, 2 g, 5 g, and 10 g of shade-dried cypress leaf powder was added in three replicates. Data was collected weekly for 5 weeks and analysis of variance was done. The study was conducted in a laboratory of the Teaching and Research farm in the University of Buea, Cameroon, in a randomized complete design. Results: Mortality of S. zeamais was significantly affected (F = 126.67, df = 3, 8, p < .001) by different doses of cypress leaf powder. The mean mortality was 0%, 40.47%, 50.6% and 70.67% for control, 2 g, 5 g and 10 g of cypress leaf powder, respectively. Grain damaged (%) and holed grain were also influenced by cypress leaf powder. The highest grain damaged and holed grain were from the control treatment. A strong positive correlation (r = 0.814, p < .001) was observed between grain damaged and holed grain while a strong negative correlation was observed between mortality and holed grain (r = -0.926, p < .001), and grain damaged (r = -0.913, p < .001). Conclusion: It is revealed that cypress leaf powder can alter some metabolic activities of S. zeamais, thus it can play a role in an integrated pest management program (IPM) of S. zeamais in maize storage.

2019 ◽  
Vol 27 (5) ◽  
pp. 400-411
Author(s):  
Henrique Delevati Fagundes ◽  
Rafael Gomes Dionello ◽  
Lauri Lourenço Radünz ◽  
Francisco Wilson Reichert Júnior

The insect known as maize weevil (Sitophilus zeamais) is one of the most important pests of stored corn in Brazil. Among the various forms of control, one can highlight the use of inert powders, which has advantages of not providing risk to the environment or to human and animal health, besides not having reports of insect resistance. Thus, this work evaluated the effect of different doses of diatomaceous earth on the development of Sitophilus zeamais on two temperature conditions on corn grain storage. A completely randomized design was adopted in a factorial 4x2x4 (diatomaceous earth dose x storage temperature x storage time) dosage, with three replicates. The diatomaceous earth doses were: 0, 250, 500 and 1000 g t-1 and subsequently stored at temperatures of 22 and 30°C for 90 days. The bulk density decreased during the storage for all diatomaceous earth doses applied, but in inverse proportion to the dose increment. Diatomaceous earth has proven better efficiency in the control of S. zeamais, with increase in dose and storage temperature. Dry weight decrease was observed in all doses and storage temperatures evaluated, but it was more pronounced in those grains that have not received the application of diatomaceous earth.


Author(s):  
C. P. O. Emeka ◽  
F. K. Ewete ◽  
S. T. Ebeniro

Annually, Nigeria loses 20–40% of maize grain due to insect pests attack. However, insect pest control in stored products relied heavily on the use of gaseous fumigants and residual contact insecticides. The control method is limited as it is toxic to beneficials and humans. Efforts have now shifted to the use of edible plant materials as protectants of which the tropics are well endowed with. Therefore, a study was conducted in laboratory in order to evaluate the effectiveness of powders of eucalyptus leaf (Eucalyptus camaldulensis Schlecht,) moringa seed (Moringa oleifera Lam.) and Pirimiphos-methyl against maize weevil (Sitophilus zeamais) on stored maize (Zea mays L.). camaldulensis leaf powder showed 100% repellence effect at a concentration of 2.0 g / 20 g maize seeds while M. oleifera seed powder had 75% repellence effect against S. zeamais. Contact toxicity of E. camaldulensis leaf powder on S. zeamais was 65% at 1.0 g/20 g maize seeds after 96 hours of exposure. Contact toxicity of M. oleifera seed powder on S. zeamais was 60% at 96 hours of exposure at a concentration of 1.0 g/20 g maize seeds. The powders of E. camaldulensis leaf and M. oleifera seed showed promising effects against S. zeamais in stored maize, hence could be incorporated in an integrated approach as alternative to synthetic pesticides when used in reducing weevil infestation in stored maize seeds.


2014 ◽  
Vol 54 (2) ◽  
pp. 132-138 ◽  
Author(s):  
Ifeanyi Daniel Nwachukwu ◽  
Elechi Franca Asawalam

Abstract Freshly prepared garlic (Allium sativum L.) juice, containing the antimicrobial allicin, was evaluated as a possible grain pro-tectant against the maize weevil, Sitophilus zeamais (Motsch.). Each experiment was set out in Completely Randomized Design (CRD) with four replications, and there was a control treatment. Adult mortality and weight loss percentage were investigated. There was an observed increase in adult mortality following days of exposure in all treatments. Statistically significant (p < 0.05) reduced grain loss was also observed in all the treatments when compared with the control. The juice samples were freshly prepared from an indigenous Nigerian garlic cultivar (GUN) and a cultivar purchased from a supermarket in Germany (GAG). These garlic juice samples exhibited lethal effects causing at least 90% adult mortality in contact toxicity tests. The amount of allicin in GUN was 1.88 mg/ml according to High Pressure Liquids Chromatography (HPLC) analysis, while the amount of allicin in GAG was 3.50 mg/ml. This study highlights the potential of A. sativum containing allicin for biorational control of maize grains against S. zeamais infestation and damage.


2018 ◽  
Vol 35 (1) ◽  
pp. 167-172
Author(s):  
S. Tiwari ◽  
R. B. Thapa ◽  
S. Sharma

A study was conducted at Entomology Laboratory of Agriculture and Forestry University with the aim of evaluating the efficacy of potential plant materials to manage the maize weevil; Sitophilus zeamais Mots. (Coleoptera: Curculionidae) from April to October 2015. The mean temperature and RH of storeroom during the experiment period was 29.37°C and 71.91% RH. A completely randomized design (CRD) was laid out with three replicates. Seven plant materials such as Acorus calamus (rhizome powder) @ 10gm kg-1, Azadirachta indica (seed powder) @ 10gm kg-1, Artemisia vulgaris (leaf dust) @ 10gm kg-1, Zanthoxylum alatum (fruit powder) @ 4gm kg-1, Melia azadirach (seed powder) @ 10gm kg-1, Justicia adhatoda (leaf dust) @ 10gm kg-1 and control were used as treatments. After six months, the lowest percentage maize weight loss (1.5) and lowest grain damage (1.43%) was observed in Acorus calamus treated grains. However, the highest grain damage percentage (18.02%) and weight loss (57.30%) was recorded in control treatment. Similarly, the lowest number of exit holes (3.30) was observed in Acorus calamus treated grains but highest (47.00) were recorded in control. Significantly more numbers of weevil were emerged (57.00) in control treatment whereas only a few (2.70) were recorded in Acorus calamus treated grains. Hence, it is concluded that maize weevil showed less preference to Acorus calamus treated grains with minimum weight loss and less grain damage as compared to other botanicals. This finding is important for promoting locally available botanical materials to manage maize weevil in Nepal.


1994 ◽  
Vol 33 (03) ◽  
pp. 246-249 ◽  
Author(s):  
R. Haux ◽  
F. J. Leven ◽  
J. R. Moehr ◽  
D. J. Protti

Abstract:Health and medical informatics education has meanwhile gained considerable importance for medicine and for health care. Specialized programs in health/medical informatics have therefore been established within the last decades.This special issue of Methods of Information in Medicine contains papers on health and medical informatics education. It is mainly based on selected papers from the 5th Working Conference on Health/Medical Informatics Education of the International Medical Informatics Association (IMIA), which was held in September 1992 at the University of Heidelberg/Technical School Heilbronn, Germany, as part of the 20 years’ celebration of medical informatics education at Heidelberg/Heilbronn. Some papers were presented on the occasion of the 10th anniversary of the health information science program of the School of Health Information Science at the University of Victoria, British Columbia, Canada. Within this issue, programs in health/medical informatics are presented and analyzed: the medical informatics program at the University of Utah, the medical informatics program of the University of Heidelberg/School of Technology Heilbronn, the health information science program at the University of Victoria, the health informatics program at the University of Minnesota, the health informatics management program at the University of Manchester, and the health information management program at the University of Alabama. They all have in common that they are dedicated curricula in health/medical informatics which are university-based, leading to an academic degree in this field. In addition, views and recommendations for health/medical informatics education are presented. Finally, the question is discussed, whether health and medical informatics can be regarded as a separate discipline with the necessity for specialized curricula in this field.In accordance with the aims of IMIA, the intention of this special issue is to promote the further development of health and medical informatics education in order to contribute to high quality health care and medical research.


2015 ◽  
Vol 5 (4) ◽  
pp. 236-243
Author(s):  
Sylvia A. Opiyo ◽  
Lawrence O. A. Manguro ◽  
Dorothy A. Okoth ◽  
Anjeline A. Ochung ◽  
Charles O. Ochieng

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 532
Author(s):  
William R. Patiño-Bayona ◽  
Leidy J. Nagles Galeano ◽  
Jenifer J. Bustos Cortes ◽  
Wilman A. Delgado Ávila ◽  
Eddy Herrera Daza ◽  
...  

Chemical control of the maize weevil (Sitophilus zeamais) has been ineffective and presents serious collateral damage. Among plant-derived insecticides, essential oils (EOs) are suitable candidates to control this stored products pest. In this work, the insecticidal activities of 45 natural EOs against S. zeamais adults were screened, and the most promising ones (24 EOs) were characterized by GC–MS. The repellent and toxic effects (contact and fumigant) of these 24 EOs were determined, and by a cluster analysis they were classified into two groups considering its fumigant activity and contact toxicity. For the EOs with the highest fumigant potential (14 oils) and their main active constituents (17 compounds), lethal concentrations were determined. The most active EOs were those obtained from L. stoechas and L. alba, with LC50 values of 303.4 and 254.1 µL/L air and characterized by a high content of monoterpenes. Regarding the major compounds, the oxygenated monoterpenes R-(+)-pulegone (LC50 = 0.580 mg/L air), S-(-)-pulegone (LC50 = 0.971 mg/L air) and R-(-)-carvone (LC50 = 1.423 mg/L air) were the most active, as few variations in their concentrations significantly increased insect mortality.


2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Gang Lin ◽  
Jingying Fu ◽  
Dong Jiang ◽  
Jianhua Wang ◽  
Qiao Wang ◽  
...  

Epidemiological studies around the world have reported that fine particulate matter (PM2.5) is closely associated with human health. The distribution of PM2.5concentrations is influenced by multiple geographic and socioeconomic factors. Using a remote-sensing-derived PM2.5dataset, this paper explores the relationship between PM2.5concentrations and meteorological parameters and their spatial variance in China for the period 2001–2010. The spatial variations of the relationships between the annual average PM2.5, the annual average precipitation (AAP), and the annual average temperature (AAT) were evaluated using the Geographically Weighted Regression (GWR) model. The results indicated that PM2.5had a strong and stable correlation with meteorological parameters. In particular, PM2.5had a negative correlation with precipitation and a positive correlation with temperature. In addition, the relationship between the variables changed over space, and the strong negative correlation between PM2.5and the AAP mainly appeared in the warm temperate semihumid region and northern subtropical humid region in 2001 and 2010, with some localized differences. The strong positive correlation between the PM2.5and the AAT mainly occurred in the mid-temperate semiarid region, the humid, semihumid, and semiarid warm temperate regions, and the northern subtropical humid region in 2001 and 2010.


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