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السجلات المعروضة 1 -- 20 من 871
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Effects of herbicide and timing of removal on interference between barley and weeds
( Blackwell Publishing Ltd , 1988 , Article)Field experiments were done during the rainy season of 1984�85 and 1985�86 at Harma, Qatar. A weed survey of barley fields was conducted with the primary purpose of identifying the weed vegetation present. The effects of ... -
Distribution and ultrastructure of neurosecretory cells in the cerebral ganglion of the earthworm
( Wiley Subscription Services, Inc., A Wiley Company , 1988 , Article)Neurosecretory (Nsy) cells within the cerebral ganglion of Lumbricus terrestris were classified ultrastructurally. The Nsy cells within the subesophageal ganglion, nerve cord ganglion, and the peripheral nervous system ... -
Vegetation composition of a maritime salt marsh in Qatar in relation to edaphic features
( Blackwell Publishing Ltd , 1990 , Article)Coverpercentage values for plant species were estimated using the line-intercept method along two belt transects starting at the lower mangrove frontier and ending at the upper height of the salt marsh. Twelve perennial ... -
Helminth parasites of fishes from two inland lakes in Egypt
( Nihon Kiseichu Gakkai , 1990 , Article)Results of helminthological examination of 1243 fishes, caught from two inland lakes, with unique and contrasting hydrobiological features at Fayoum Governate in Egypt, are presented. General incidence of trematodes, ... -
Photosynthetic acclimation to high temperatures in wheat
( John Wiley & Sons, Ltd. , 1992 , Article)Growth and photosynthetic performance were assessed for the Finnish wheat Triticum aestivum L. var. APU under a cool (13/10�C day/night) and a warm (30/25�C day/night) regime. Plants exhibited a certain degree of acclimation ... -
Effects of substituting fish meal with Azolla pinnata in practical diets for fingerling and adult Nile tilapia, Oreochromis niloticus (L.)
( Blackwell Publishing Ltd , 1992 , Article)Dry and fresh Azolla pinnata were evaluated as feed ingredients for fingerling and adult Nile tilapia, Oreochromis niloticus (L.). Dry Azolla was incorporated into practical diets containing approximately 30% crude protein ... -
Effect of gamma radiation on the morphology and Thermophysical properties of the pollen wall of Phoenix dactylifera L.
( Qatar University , 1994 , Article)Pollen grains of Phoenix dactylifera were exposed to different doses of gamma radiation (250,500,1000 rad and 1 M rad). To access the effect of radiation on the external morphology of the pollen grains, they were examined ... -
Effects of Stocking Density and Feeding Levels on Growth Rates and Feed Utilization of Rabbitfish Siganus canaliculatus
( John Wiley & Sons, Ltd. , 1995 , Article) -
Expansion of fisheries in Qatar (1980-1992): Growth of an artisanal fleet and closure of a trawling company
( Elsevier Science B. V. , 1995 , Article)Total fish landings in Qatar increased from 1736 t per annum in 1980 to 7845 t in 1992. Ninetythree percent of this growth was due to an increase in the artisanal fleet exemplified by increases in: (i) numbers of vessels ... -
Eutrophication in the coastal waters of Alexandria following the increase in phosphorus load
( Parlar Scientific Publications , 1996 , Article)Samples from the coastal waters of Alexandria during 1991-1993 indicate a remarkable increase in the phosphorus load from 870 to 1140 kg y-1 compared to 567 kg y-1 in 1986 raising the average phosphorus from 1.01 to 1.47 ... -
Purification and characterization of an extracellular phenol oxidase from culture filtrates of Pyricularia oryzae
( NRC Research Press , 1996 , Article)Extracellular phenol oxidase activity was characterized and compared in Pyricularia oryzae wild-type and albino cell types to determine if this phenol oxidase was responsible for lack of melanization in the albino culture. ... -
Water stress and gibberellic acid effects on growth of fenugreek plants
( Springer Berlin / Heidelberg , 1998 , Article)Fenugreek plant is susceptible to water stress during the vegetative growth stages, since a soil matric potential lower than -0.3 MPa causes substantial reduction in growth parameters such as height, weight and total leaf ... -
Helminth parasite larvae collected from Arabian Gulf fish II. first record of some trybanorhynch cestode from economically important fish
( Arab Bureau of Education for the Gulf States , 1999 , Article)Metacestodes of 14 different trypanorhynch larvae were found infesting Arabian Gulf economically important fish along the coasts of the United Arab Emirates. Except for Grillotia and Pterobothrium, all other larvae were ... -
Helminth parasites of fishes from the Arabian Gulf 9. some hemiurids (Digenea) from fishes of Qatari waters
( Istituto di Parassitologia Medica , 2001 , Article)Four Hemiurids collected from some marine fishes caught off Qatari waters int he Arabian Gulf are described and compared with related species previously reported from the Arabian Gulf and the Indian Ocean. These include ... -
Preliminary Survey on Parasites Infecting Some Amphibian and Reptilian Species from United Arab Emirates and Qatar
( Qatar University , 2002 , Article)The common amphibian toad Bufo orientalis and four species of reptiles (Scincus muscatensis, Mabuya brevicolis, Uromastyx microlepis and Diplometopon zarudnyi) were collected from five localities in the United Arab Emirates ... -
First record of microsporedean and myxosporeans (Protozoa) infecting some Arabian Gulf fish off the coasts of Emirates and Qatar with a description Myxobolus arabicus n.sp
( Arabian Gulf University , 2002 , Article)During a comprehensive survey carried out on helminth parasites of Arabian Gulf fishes mainly from the coasts of the Emirates and Qatar, two microsporeans and three myxosporeans Protozoa were reported and described for the ... -
Monogenea of Arabian Gulf fishes 1. Descriptions of three Capsala spp. (Capsalidae) including Capsala naffari n. sp. infecting mackerel tuna Euthynnus affinis from coasts of Emirates
( Elsevier , 2002 , Article)Three species of the genus Capsala including Capsala naffari n. sp., C. neothunni (Yamaguti, 1968) and C. nozawae (Goto, 1894) are recorded and described from the buccal cavity of mackerel tuna Euthynnus affinis caught ... -
Monogenea of Arabian Gulf fishes. 3. Encotyllabe spari and E. kuwaitensis (Capsalidae) from Qatari waters
( Instituto di Parassitologia Medica , 2002 , Article)Two species of monogenea of the subfamily Encotyllabinae, genus Encotyllabe were observed from Qatari fishes which collected between March and May, 2002 from 5 Khors of Qatari coastal line; Al-Odaid, al-Dhakhira, Ras Rakan, ... -
Redesciption of Ten species of digenetic trematodes from marine fish of Emirati coastsof the Arabian Gulf
( Arab Bureau of Education for the Gulf States , 2003 , Article)Ten species of digenetic trematodes are fully described from fishes of the United Arab Emirates. These specimens, which have been previously described in a list which comprised different helminth fauna, commonly infest ... -
Helminth parasite larvae collected from Arabian Gulf fish III. first report on genus Dasyrhynchs Pintner 1928 (Cestoda: Trypanorhyncha) with a key depending on morphology of plerocercoid larva
( Universita Di Messina, Istituto Di Parassitologia Medica , 2003 , Article)Two trypanorhynchan cestode larvae related to genus Dasyrhynchus are reported for the first time from Emirati coastal waters, Arabian Gulf. The first is Dasyhynchus sp. collected as encysted. larvae from body cavity of ...