Refinar búsqueda
Resultados 771-780 de 1,480
Effect of sowing dates of three cowpea cultivars on their infestation rate with cowpea pod borer Etiella zinckenella
2011
Helalla, A.A.R. | Ali, F.A.F. | Hegab, M.F.A. | Kamal, Kh.A.
Field trials were conducted during 2005 and 2006 seasons at Minofia governorate to evaluate the effect of planting date of three cowpea cultivars on their infestation rate with cowpea pod borer, Etiella zienckenella. For each cowpea cultivar planted at each tested date, the numbers of bores and larvae were counted in green and dry pods as well as in dry seeds and the means were obtained to estimate the degree of insect infestations. Results indicated that, regardless the planting date in both seasons, Kream7 was the highest resistant cultivar to insect infestation followed by Kaha l and then Kafr El Shikhl. On the other hand, regardless the cowpea cultivar, the rate of insect infestation was greatly reduced at the early plantation. Thus, selection of Kream7 cultivar and early plantation could be involved in reducing E. zinckenella infestation and subsequently increase the cowpea yield. These studies clearly demonstrated that several non-insecticidal approaches have great potential for cowpea pod borer Etiella zinckenella management. These approaches include some of integrated pest management strategies which can effectively prevent or reduce infestation.
Mostrar más [+] Menos [-]Taxonomic study of two genus in lice linognathus africanus kellogg, and paine, 1911 bovicola, damalinia,ovis 1781 by scanning electronic microscope, sem
2011
Aljubran, S.A. | Alsaqabi, S.M.
This study presents the Mallophaga and Anoplura lice which affects farm animals (camels sheep and goats), a local area east of the Saudi Arabia of different ages, races, classes. Study the classification of lice was recorded as using the optical microscope and electronic scanning. The study shows scanning electron microscopy micro-structure of the species: Bovicola (Damalinia) ovis, Linognathus africanus and the study showed the installation of a portfolio of head lice, and the distribution of filament head, chest and abdomen, as shown over the centuries, the difference in the form of remote sensing and Swallows in thesexuallice, the first study in this area.
Mostrar más [+] Menos [-]Ultrastructure of the sheep nose myasis oestrus ovis, linnaeus, 1758 and camels nose myasis cephalopina titillator, clark, 1797 in Saudi Arabia farms
2011
Aljubran, S.A. | Alsaqabi, S.M.
Farm animals have a high economic importance because of their important products such as meat, milk, hair as well as skin, not only in our country but also all over the world. These animals can be infected by serious pathogens, external and internal parasites causing severe damage, which result in losses of animal production. Accordingly, the study of external parasites with light microscope and scanning electron microscope were recorded, to clarify the exact composition of species. Also, differences in the morphological characteristics between the two Myiasis species: Oestrus ovis (Linnaeus, 1758) and Cephalopina titillator (Clark 1797), were investigated.
Mostrar más [+] Menos [-]THE CRITICAL PERIOD OF WEED COMPETITION OF DIRECT SEEDED RICE IN SALINTY LAND Texto completo
2010
El-Shennawy Rania | M.M. Omran | F.A. Abd El-Motteleb
Two Field experiments were conducted during the two summer seasons of 2007 and 2008 at EL-Serw Agricultural Research Station, Damietta Governorate, Egypt to study the effect of the time removal of weeds on associated weeds, growth, yield and its components in direct seeded rice in salinity land. Echinochilon crus – galli, Echinochilon colunum, Cyperus difformis, Cyperus longus and Dicanthium annulatum were the major weed species. Competition beyond 8 and 10 weeks from sowing and weed competition for the whole season caused drastic reduction in the panicle length, number of panicles / m2 weight of 1000grain and grain yield. Grain yield of rice increased significantly with the increase of the duration of weed-free period. Weed free for the whole season and weed free for 10,8,6 and 4 weeks from sowing and weed removal at 4 and 6 weeks from sowing gave good results in this respect in both seasons. The period during 4 and 6 weeks after sowing was found to be an important factor in crop/weed competition. Weed cause 20 to 95% yield loss. Direct seeded rice ecosystems are most vulnerable to weed competition. Weed free is the most common and predominant method of control and is cost-effective. In direct seeded rice emergence of weeds begins with the germinating rice seedlings. This leads to competition between weeds and crop right from the very early stages. The degree of yield losses would depend on the type of weeds and the stage and duration of their competition with the crop. It could be concluded that the critical period of weed competition in direct seeded rice among 4- 6 weeks from rice sowing, thus it's important to remove the weeds at this time.
Mostrar más [+] Menos [-]SOME FACTORS AFFECTING SUCCESSFUL APIS MELLIFERA QUEEN REARING IN SOHAG Texto completo
2010
I.M El-Metwally | R.M.H Tagour
Studies were accomplished to identify the important factors affecting successful virgin queens production in Sohag during 2007 and 2008 years. In order to find out the best teaching for rearing virgin queens by grafting method. Markedly differences in the mean number of virgin queens between single and double grafting methods, specially in spring and autumn seasons; in spring mean number of accepted cells of 43.77 with 37.66 emerged queens and 49.85 with 47.07 emerged queens were obtained when single and double grafting were used methods respectively. Spring season was favorable for queens rearing, followed by autumn and summer, while winter season came the latest. There was a clear relationship between larval age at grafting and the larval acceptance, one day old worker larvae gave the highest number of virgin queens emerged. On the other hand, the queen must be removed outside the hive 48 hrs before starting larval grafting to obtain the highest numbers of accepted queen cells. In general, double grafting, situating the cell cups frame in the hive center of the hive and fitting the cell cups on the top and bottom bar, gave the best method for queens acceptance and queens production. However, cell cups fitted on the edges of the bars were successfully reared when ambient temperatures were high in spring season, but queen cells in the center of the hive's brood nest were correlated with higher temperature and had a greater chance for emergence.
Mostrar más [+] Menos [-]TOLERANCE OF HONEY BEE COLONIES TO VARROA DESTRUCTOR (ANDERSON AND TRUEMAN) AND THE ECONOMIC THRESHOLD OF THE PARASITE IN THE CENTRAL REGION OF KINGDOM OF SAUDI ARABIA Texto completo
2010
. Omran Nageh, S.M | Mabrouk ; M.S.O. | Mohanna K.M.
Experiments were carried out on honey bee colonies (Apis mellifera) during the winter of 2008 and spring of 2009 using colonies wintered with five levels of varroa infestation (0.0, 3.8, 9.0, 13.1 and 22.9%) in the Central Region of the kingdom of Saudi Arabia. The goal of the present work is to determine varroa treatment thresholds and colony collapse level. Response variables examined included varroa mite infestation level (%), cm2 of brood number of frames of brood, number of frames covered with adult honey bees and mites recovered on sticky boards. The data obtained reveled that no significant differences were noticed in cm2 of brood, number of frames of brood, and number of frames of bees in colonies (range of 0.0 to 9.0% varroa infestation or 0.0 – 0.9 mites/bee). Colonies with 13.1% infestation (0.13 mites/bee) exhibited a significant reduction in all measures of performance. The present results suggested that honey bee colonies can tolerate a level of 9.0% varroa infestation (0.9 mites/bee) during the winter without evidence of colony injury. It also suggested that 13.1% infestation (0.13 mites/bee) is the colony collapse or economic injury threshold in the Central Region of the Kingdom of Saudi Arabia. Also colonies with 12.3 or more mites falling on sticky boards after 48-hour period were likely to have lower populations of bees and brood the following spring.
Mostrar más [+] Menos [-]SELENIUM INDUCES ANTIOXIDANT DEFENSIVE ENZYMES AND PROMOTES TOLERANCE AGAINST SALINITY STRESS IN CUCUMBER SEEDLINGS (Cucumis sativus) Texto completo
2010
Se, Selenium; ROS, Reactive oxygen species; APX, Ascorbate peroxidase; CAT, Catalase; PAL, Phenylalanine ammonia-lyase; EDTA, Ethylenediamine tetra acetic acid; MDA, Malondialdehyde; POD, Peroxidase; PVP, Polyvinylpyrrolidone; SOD, Superoxide dismutase; TBA, Thiobarbituric acid; TCA, Trichloroacetic acid; NBT, Nitroblue tetrazolium; P5CR, ∆1-Pyrroline-5-carboxylate reductase; P5CS, ∆1-Pyrroline-5-carboxylate synthetase. OAT, Ornithine-δ-aminotransferase; P5CDH, ∆1-Pyrroline-5-carboxylate dehydrogenase and PDH, Proline dehydrogenase; Poly acrylamide gel electrophoresis (PAGE) ABSTRACT Selenium (Se) is not an essential nutrient for higher plants. Although, it is able to induce stress tolerance in many plant species. The present study was carried out to investigate the ability of Se to promote the tolerance of cucumber seedlings to salinity stress and to identify some biochemical parameter associated with Se–induced resistance in cucumber seedlings. Plants were irrigated with 2000 ppm NaCl after treatment with 1ppm Se for two weeks and samples collected after 7 days from started salt-treatment. The biochemical changes due to treatment with Se and /or NaCl were monitored by determination of lipid peroxidation (LPO), proline, phenolic compounds and percentage of electrolyte leakage (EL) from plant tissues. Moreover, the activities of peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD) and phenylalanine ammonialyase (PAL) were determined. The treatment of cucumber seedling with salinity (2000 ppm NaCl) in the presence or absence of selenium caused a remarkable elevation in free proline concentration and the level of phenolic compounds. Salinity stress caused a high level of lipid peroxidation which led to increase the percentage of electrolyte leakage from plant tissues. Se treatment caused a significant reduction in electrolyte leakage and malondialdehyde concentration of cucumber seedlings. The specific activities of antioxidant enzymes (POD, SOD, and APX) and PAL were significantly increased by the treatment with NaCl. Also, Se caused a significant elevation in the specific activities of POD, CAT, SOD, APX and PAL in cucumber seedlings grown under salt stress condition. On the other hand, Se caused a significant decrease in SOD activity in cucumber seedlings grown in non-salty condition. The isoenzymes pattern of POD demonstrated that peroxidase was up-regulated by Se either in control or NaCl-treated seedlings. The results concluded that Se induce six POD isoenzymes in cucumber seedlings. Se reduces and overcomes the oxidative injury caused by salinity stress. Moreover, the protective effect of Se against salinity stress may be carried out through a mechanism included activation of PAL which is responsible for phenolic compounds biosynthesis. The accumulation of these phenolic compounds in Se-treated seedling leads to a high activities of antioxidant defensive enzymes and increase the tolerance level towards salinity stress.
Mostrar más [+] Menos [-]EFFECT OF PHOSPHORUS FERTILIZER TREATMENTS ON INCIDENCE OF FUSARIUM ROOT-ROT/WILT DISEASE COMPLEX, AND ON YIELD COMPONENTS OF LUPINE, CHICKPEA AND LENTIL CROPS Texto completo
2010
A Elhassan | A El-Tilib | Ibrahim ; H.S. | A.H. Awadelkarim
In greenhouse and field experiments, conducted in two successive winter seasons 2007/2009 the effect of phosphorus fertilizer treatments on incidence of wilt disease of lupine, chickpea and lentil, as well as yield and yield component was studied. Application of Phosphorus fertilizer (100 and 200 kg/fed; as super phosphate (15.5% P2O5) before planting) caused a reduction in incidence and severity of wilt diseases on plants of the three legume crops either in greenhouse and field experiments. In field experiments, results indicated that the most effective treatment was phosphorus at 100 and 200 kg / fed) respectively, which reduced the wilt diseases. Phosphorus fertilizer significantly increased yield characters i.e., plant height, number of branches, number of pods, seeds yield / plant and weight of 100 seeds.
Mostrar más [+] Menos [-]DESIGNING AN INTEGRATED COMPUTER PROGRAM FOR VEGETABLE INSECT, NON INSECT PESTS AND DISEASES AFFECTING VEGETABLE CROPS Texto completo
2010
Abdulrahman Aldawood | Ibrahim Alshahwan | Abdullah Al-Sadon | Abdulrahman Al-Azba | Omar Abdalla | Alshamy Adam | Ali Almasrahy
The major vegetable crop production in the Kingdom of Saudi Arabia require easily produced sources of related information. However, there is a lack of such studies that lead to the use of com-puter programs or geographical information sys-tems in developing an electronic source for these extension, research, and scientific data. Farmers and agricultural engineers need a comprehensive database regarding insect pests, non insects pests, and diseases infecting vegetable crops in Saudi Arabia in Arabic language. Therefore, this project has been executed to design a complete database of such information. Included in this software are colored photographs, which will help users to get acquainted with methods of manage-ment of these pests and diseases. A data sheet has been designed to collect field information for each vege-table crop, including its pests and dis-eases, through field trips for many farms in all the 13 agricultural regions of Saudi Arabia. This field information has been compiled with what has been published in related scientific references. Upon completion of this program, confirmatory trips for five regions had been made in order to meet with farmers, agricultural engineers, and extension agents who are in agricultural branches of the Min-istry of Agriculture in these visited regions. The objectives of these trips were to get feedback about this program. Finally, an elaborate imple-mentation guide was prepared under the title "De-signing an integrated computer program for vege-table cultivation in The Kingdom of Saudi Arabia." Also, an attached manual, regarding the compo-nents and the operation of this program, was made. All of these materials have been distributed to farmers and interested people in the agricultural sector
Mostrar más [+] Menos [-]FORMULATION AND EVALUATION THE NEMATICIDAL ACTIVITY OF CERTAIN PLANT OILS AGAINST CITRUS NEMATODE Tylenculus semi-penetrans Texto completo
2010
, A.M.A El-Kady | S. Ibrahim Hala | . Farag E.M.A | El-Torkey H.M.
Four plant oils namely Barka, Sesam, Garlic and Almond were prepared as emulsifiable concentrate (EC). Polyethylene glycol 600 dioleate (PEG 600 DO), Toximol R and Toximol H were used as emulsifiers while xylene and toluene used as solvents. Four formulations only passed successfully (F1, D2, C3 and E5) in thePhysico-chemical properties according to the standards of WHO. The results indicated that the successful prepared formulations showed different degrees of effectiveness against second stage juveniles of Tylenculus semipenetrans under laboratory conditions. Second stage juveniles seem as paralyze at 24 hrs, whereas this effect disappears completely after 72 hrs in case of Almond and Barka. On the other hand, the effect of Sesam and Garlic showed a slight effect at 24 hrs and increased gradually to give highly effectiveness after 72 hours. According to EC50 values at 72 hrs, Garlic was more effective than Sesam. The respective EC50 values were 0.6 and 2 mg/ml. These results emphasized the promising effect of certain plant oil formulations including Garlic and Sesam oil against pathogenic nematode, and that such formulation might be used for nematode control in small areas, as gardens and plant nursery.
Mostrar más [+] Menos [-]