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Bounechada M Doumandji SE 《Communications in agricultural and applied biological sciences》2004,69(3):211-218
Ocneridia volxemi Bolivar (Pamphaginae, Orthoptera) is one of the important insects pest in the heigh plains of north east of Algeria. Larval and adult stages caused severe damage to the leaves of cereals and an other various crops. Laboratory studies were conducted to the determine the potential of the fungus Beauveria bassiana for the control of the pest of larval and adults. Positive results were obtaved when larvae and adults were sprayed with different concentration of fungus conidia (D1: 2 x 10(6) conidia/ml, D2: 5 x 10(5) conidia/ml, D3: 8 x 10(4) conidia/ml, D4: 10(2) conidia/ml). Concentration at D1 and D2 in an oil formulation showed respectively 100% and 90 % larval mortality at the first day of treatment and 100%-9% adults mortality at the five day of treatement. The results revealed that the rates of infection and mortality were significantly related to the concentration of conidia in the corresponding samples. Beauveria bassiana can be considerd as a promising biocontrol agents of Ocneridia volxemi may be an other locuts, but field experimentation is necessary to subtantiate these finding. 相似文献
3.
REINHARD B
SE KARL T. FRIEDHOFF SYLVIA OLBRICH 《The Journal of eukaryotic microbiology》1987,34(1):110-113
Four fallow deer, Cervus dama, became infected with Trypanosoma (Megatrypanum) sp. by oral application of triturated guts from tabanids collected in an area with deer but without any cattle; four control calves remained negative. Upon challenge with triturated guts from tabanids from an area with pastured cattle, the four calves became infected with Trypanosoma (M.) theileri. The prepatent period in deer was five days or less. Haematopota spp. and Tabanus spp. were identified as vectors of the deer trypanosomes. It is concluded that the trypanosomes of C. dama belong to a Megatrypanum species that is not identical with T. theileri. 相似文献
4.
Youcef Merzouki Karim Souttou Makhlouf Sekour Samia Daoudi-Hacini Salaheddine Doumandji 《Comptes rendus biologies》2014,337(1):53-61
The diet of the House Martin Delichon urbica was analyzed in a suburban area in Pins maritimes, northeast of Algiers (Algeria). The diet was determined by analyzing 120 faecal samples collected from a breeding colony between April and September 2007. Insects were the most numerous prey types (99.86%). Hymenopterans were the dominant preys (56.99%), followed by Coleopterans (20.14%), Homopterans (14.22%), Heteropterans (5.45%), and Dipterans (3.10%). Division of the prey items into families demonstrated that the highest relative frequency was large Hymenopterans in the family Formicidae (54.0%). The dominant species in the diet was Tetramorium biskrensis, which comprised 32.6% of the diet. It was followed by Camponotus barbaricus (6.9%) and Monomorium salomonis (5.6%). Comparison between diet and availability of preys using the Savage index showed that T. biskrensis, Crematogaster scutelaris, Pheidole pallidula, Diptera sp. unident. and Aphidae sp. unident. were positively selected by D. urbica. 相似文献
5.
The apple rootstock,A106(Malus sieboldii),had 17 bivalents in pollen mother cells at meiotic metaphase 1,and 17 chromosomes in a haploid pollen cell.Karyotypes were prepared from root-tip cells with 2n=34 chromosomes,Seven out of 82 karyotypes(8.5%) showed one pari of satellites at the end of the short arm of chromosome 3.C-bands were shown on 6 pairs of chromosomes 2,4,6,8,14,and 16 near the telomeric regions of short arms.Probes for three ripening-related genes from Malus x domestica:endopolygalacturonase(EPG,0.6kb),ACC oxidase(1.2kb),and ACC synthase(2kb)were hybridized in situ to metaphase chromosomes of A106.Hybridization sites for the EPG gene were observed on the long arm of chromosome 14 in 15 out of 16 replicate spreads and proximal to the centromere of chromosomes 6 and 11.For the ACC oxidase gene,hylridization sites were observed in the telomeric region of the short arm of chromosomes 5 and 11 in 87% and 81% of 16 spreads respectively,proxiaml to the centromere of chromosome 1 in 81% of the spreads,and on the long arm of chromosome 13 in 50% of the spreads. Physical mapping of three fruit ripening genes in an apple rootstock A106.Twenty five spreads were studied for the ACC synthase gene and hybridization sites were observed in the telomeric region of the short arm of chromosome 12 in 96% of the spreads.chromosomes 9 and 10 in 76% of the spreads,and chromosome 17 in 56% of the spreads. 相似文献
6.
Hernandez-Trejo A B Estrada-Drouaillet JA López-Santillán C Rios-Velasco SE Varela-Fuentes R Rodríguez-Herrera E Osorio-Hernández 《Phyton》2019,88(1):47-54
The control of Spodoptera frugiperda is basedon synthetic insecticides, so some alternatives are the use ofentomopathogenic fungi (EF) and neem extract. The objective ofthe study was to evaluate in vitro effectiveness of native EF andneem extracts on S. frugiperda larvae. Six EF were identified byDNA sequencing of ITS regions from three EF (Fusarium solani,Metarrhizium robertsii, Nigrospora spherica and Penicilliumcitrinum). They were evaluated in concentrations of 1 × 10⁸ spores/mL. In addition, a second bioassay was carried out evaluatingonly F. solani, M. robertsii and N. sphaerica and the additionof vegetable oil. On the other hand, extraction of secondarymetabolites from neem seed (Azadirachta indica) was carriedout by performing, mass (g) and solvent volume (mL ethanoland water) combinations, which were subjected to microwavesand ultrasound. Subsequently, these extracts were evaluatedin concentrations of 3%, 4% and 5%. A survival analysis wasperformed for each of the bioassays. With respect to the resultsof the first bioassay, F. solani obtained a probability of survival of0.476 on the seventh day, while in the second bioassay, M. robertsiiobtained 0.488 survival probability. This suggests that the expectedpercentage of larvae that stay alive on the sixth day is 48.8%.However, in the evaluation of the neem extract the combination1:12/70% to 4% caused 84% mortality of larvae. The use of nativeHE and neem extracts has potential for the control of S. frugiperda. 相似文献
7.
Piophila megastigmata McAlpine (Diptera: Piophilidae) is recorded for the first time from Algeria, northern Africa. This is the first Palaearctic record of the species outside the Iberian Peninsula, and the only record from Africa apart from its type locality in eastern South Africa. The current report extends significantly the known distribution in the Palaearctic Region of a species of forensic interest and of potential economic importance as a food pest. 相似文献
8.
The cytokineplast: purified, stable, and functional motile machinery from human blood polymorphonuclear leukocytes 总被引:7,自引:4,他引:7
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We examined the formation of motile, chemotactically active, anucleate fragments from human blood polymorphonuclear leukocytes (PMN, granulocytes), induced by the brief application of heat. These granule-poor fragments are former protopods (leading fronts, lamellipodia) that become uncoupled from the main body of the cell and leave it, at first with a connecting filament that breaks and seals itself. The usual random orientation of such filaments can be controlled by preorientation of cells in a gradient of the chemotactic peptide, N-formylmethionylleucylphenylalanine (F-Met-Leu-Phe) (2x10(-9) M- 1x10(-8)). Cytochalsin B, 2.5-5 μg/ml, prevents fragment formation; colchicine, 10(-5) M, does not. In scanning electron micrographs, fragments are ruffled and the cell body rounded up and rather smooth. In transmission electron micrographs, fragments contain microfilaments but lack centrioles and microtubules. Like intact cells, both bound and free fragments can respond chemotactically to an erythrocyte destroyed by laser microirradiation (necrotaxis); the free, anucleate fragments may do so repeatedly, even after having been held overnight at ambient temperatures. We propse the name cytokineplast for the result of this self-purification of motile apparatus. The exodus of the motile machinery from the granulocyte requires anchoring of the bulk of the cell to glass and uncoupling, which may involve heat-induced dysfunction of the centrosome. In ultrastructural studies of the centrosomal region after heat, centriolar structure remains intact, but pericentriolar osmiophilic material appears condensed, and microtubules are sparse. These changes are found in all three blood cell types examined: PMN, eosinophil, and monocyte. Of these, the first two make fragments under our conditions; the more sluggish monocyte does not. Uncoupling is further linked to centrosomal dysfunction by the observation that colchicines-treated granulocytes (10(-5)M, to destroy the centrosome’s efferent arm) make fragments after less heat than controls. If motive force and orientation are specified mainly from the organelle-excluding leading front, then endoplasmic streaming in PMN is a catch-up phenomenon, and microtubules do not provide the vector of locomotion but rather stabilize and orient the “baggage” (nucleus, granuloplasm)—i.e., they prevent fishtailing. Moreover, constraints emanating from the centrosome may now be extended to include, maintenance of the motile machinery as an integral part of the cell. 相似文献
9.
Bounechada M Doumandji SE Laouer H 《Communications in agricultural and applied biological sciences》2004,69(3):235-244
This study was carried out to evaluate the effect of Melia azedarach L. (Meliaceae) dry fruit extracts (oil and water) and Eucalyptus globulus Labill. (Myrtaceae) dry leaves extracts (water) on Oneridia volxemi hoppers (fifth-instar) feeding on cereals leaves (Triticum durum) under laboratory conditions. Larva feeding reduced and mortality was significatly (p < 0.05) on cereals leaves sprayed with three concentrations 0, 5, 1 and 2% of oil extracted from Melia azederach. In addition, O. volxemi feeding and mortality was significantly (p < 0.05) on cereals leaves sprayed with two concentrations 50 g/l and 80 g/l of water extracts from Melia azedarach dry fruits soaked for 24 hours. the water extract solution of 80 g/l significantly reduced feeding than the other concentrations 50 and 25 g/l. This study showed also the water extract solution from Eucalyptus globulus dry leaves reduced also feeding and induced the mortality of O. volxemi but not better than Melia azedarach dry fruit extracts water at the same concentration (80 g/l). The aim of this study is in an integrated management program for control of O. 相似文献
10.