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1.
Commun Agric Appl Biol Sci ; 79(2): 253-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26084105

RESUMO

This study aims to evaluate the efficacy of five measures; including the release of two strains of Trichogramma, Bacillus thuringiensis (B.t.). Sweetened B.t. and the environmentally friend insecticide (Tracer®), to manage the grape moth, Lobesia botrana that infested the grape vines c.v. "Thompson seedless " in Egypt severely during the two successive years of 2011 and 2012. In concern to the release of the worldwide, Trichogramma evanescens Westwood., the mean total grape yield ranged from 8.00 to 14.00 ton/fed and from 6.90 to 11.9, in respect to the two seasons and the mean infestation percentages fluctuated between 50.00 and 16.14; 43.48 and 21.01 in sequence for the same years. The corresponding grape bunches loss percentages averaged from 21.43 to 6.91; 18.63 to 9.00,respectively for the same periods of this study. Whereas, it was noticed that in releasing the indigenous T. bourarchae was more effective than T. evanescens in reducing all the above mentioned grape yield particularly. Applying Bacillus thuringiensis (B.t.) and/or adding sugar as a stimulant to improve yields reduced the infestation and the crop loss percentage. However, Bacillus thuringiensis mixed with sugar which overweighed the use of Bacillus thuringiensis alone. Although Tracer® provided good harvest in both years, but unfortunately it affected the grape berries components rather than the other treatments. Control plots indicated 48 and 50% infestation, with very low yield compared with the other five trials to manage the assigned insect pest. For the first time worldwide economics and profits were computed taking into account the whole market sale, the total control costs and the gross income to decide the most profitable treatment for the table grape growers under the Egyptian conditions. It was found that the mean (L.E.) profits/fed were arranged in a descending order as follows: 470.95, 513.28, 504.78, 500.82, 397.25 and 0.00 for Bacillus thuringiensis + sugar, Trichogramma bourarchae, Trichogramma evanescens Westwood, Dipel-2x®, Tracer® and control in respect in 2011. The corresponding values in the year 2012 were 453.85, 445.58, 427.18, 377.00, 349.18 and 0.00 for Trichogramma bourarchae, Bacillus thuringiensis + sugar, Dipel-2x®, Trichogramma evanescens Westwood, Tracer® and control in respect. The obtained results were analysed and discussed in the text.


Assuntos
Controle de Insetos/métodos , Lepidópteros/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Vitis/parasitologia , Animais , Bacillus thuringiensis/fisiologia , Egito , Lepidópteros/microbiologia , Mariposas/microbiologia , Doenças das Plantas/parasitologia
2.
Commun Agric Appl Biol Sci ; 78(2): 359-68, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25145260

RESUMO

In this study the relatedness was estimated between mother queen's colony and her daughters' queens' colonies, by extracting DNA from their individual workers offspring (N= 20) and using five microsatellite loci. Locus As indicated more diversity in the length of alleles from 130 to 162 PB with frequency from 0.05 to 0.1, followed by locus A76 that showed alleles lengths 210 to 340 PB with frequency 0.05 to 0.2 that means big diversity in the colonies individuals due to the numbers of drones mated with mother queen. On the other hand, A107 illustrated the weight of alleles from 179 to 205 PB with frequency 0.05 to 0.25. Loci B124 and ACOO6 also showed high frequency of 0.25 and indicated more relatedness. Through locus 8124 the Correlation coefficient was 1.00 between P.Q and F,.QO and 0.87 for P.Q and F1.Q1 and F,.Q3. A43 indicated relatedness through the correlation coefficient (0.968) between F.Q1.and F2.Q2. The microsatellites demonstrated that there was a genetic diversity within and between colonies.


Assuntos
Abelhas/genética , Repetições de Microssatélites , Animais , Abelhas/classificação , Feminino , Variação Genética , Masculino
3.
Commun Agric Appl Biol Sci ; 70(4): 703-14, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16628907

RESUMO

In Egypt, the chalk brood (CHB) disease caused by the fungus, Ascosphaera apis Maassen started again infesting the honeybee, Apis melifera L (Hymenoptera: Apidae) colonies after a cessation pause of seven to nine years. For the first time, an attempt has been made to look into the problem of the CHB disease from the view point of assessing losses in both clover (Trifolium alexandrinum) and chinus (Chinus molus) honey yields. In this regard, two techniques were adopted. Under the natural conditions of the experimental apiary (first technique), loss in clover honey was 18.412 +/- 0.663%, on average, whereas the average loss in chinus honey was 18.332 +/- 1.536%. In the second technique of loss appraisal (artificial infection). The tested honeybee colonies were artificially infected with four sources of A. apis infection, I.e. black mummies, white mummies, pollen grains and water, in addition to controls to create the so-called "different levels of infection". The mean percentages of losses in clover honey were 30.06 +/- 1.807, 27.95 +/- 1.062; 21.13 +/- 0.987; 16.96 +/- 0.672 and 0.00 +/- 0.00 for black mummies, white mummies, pollen grains, water and control, respectively. Taking into account the relationship between number of resulted mummies in each source of infection and % loss in clover honey, it could be concluded that as the resulted mummies increased, the corresponding clover honey yield decreased in each source of infection. It was noticed that the % loss in clover honey differed as the used technique differed. For example, the percentage loss in clover honey produced from colonies exposed to the natural conditions was relatively less than that of the artificially infected ones. This has been discussed in the text. However, the causative pathogen of CHB disease resulted in serious decrease in honey production. Loss appraisal is a perquisite step for the determination of the economic injury levels (EILs). By regressing % loss in clover honey yield against the total number of fallen mummies, the linear equation was worked out to be: Y = 0.242 + 0.040 x (r2 = 0.99, F = 62408.865). Depending on the total costs of controlling CHB disease, the EIL values were 31.875 and 11.250 mummies/colony for cedar oil and thymol granules, subsequently. As to the chinus honey the corresponding EILs were 18.940 and 6.683 mummies/colony for cedar oil and thymol granules, in respect, as a result of adopting the regression formula: Y = -6.762 + 0.101 X. As for the clover honey (artificial infection) the EIL values were 39.844 and 14.063 mummies/ colony in case of using cedar oil and thymol grains, subsequently. These values were worked out using the formula Y = 5.871 + 0.032 X. From the practical point of view, apiarists should not use thymol or cedar oil as fallen mummies don't reach the suggested EILs values to minimize control costs as much as possible.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Abelhas/microbiologia , Fungicidas Industriais/economia , Mel , Animais , Custos e Análise de Custo , Egito , Fungicidas Industriais/farmacologia , Óleos Voláteis/economia , Óleos Voláteis/farmacologia , Timol/economia , Timol/farmacologia
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