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NUMERICAL TAXONOMY STUDY ON SPECIES OF CLEOMACEAE IN EGYPT
2009
Al-Dakheel, . Almhiemd | Alnajm A.
ABSTRACT A data matrix comprising 100 characters of morphology, anatomy and seed protein banding recorded comparatively for ten species of Cleome and Gynandropsis (Cleomaceae) was analyzed under three fundamentally different numerical methods. The PRIMER analysis used the Bray Curtis (SØrensen) distance measure together with the single linkage clustering methods. The SPSS program used Ward’sclustering as a distance measure and the average linkage clustering method distance or complete linkage distance. All three dendrograms agree in grouping the ten species into two major groups: A (including C. droserifolia and C.chrysantha) and B (including C. amblyocarpa, C. paradoxa, C. arabica, C. viscosa C. brachycarpa, C. scaposa, C. hanburyana and Gynandropsis gynandra).This indicates that Gynandropsis gynandra ought to be submerged in Cleome as Cleome gynandra
Mostrar más [+] Menos [-]FACTORS AFFECTING INFESTATION PATTERN OF THE RED PALM WEEVIL, RHYNCHOPHORUS FERRUGINEUS OLIV. IN DATE PALM FARMS IN QATIF, SAUDI ARABIA
2009
Sahar A. El-Sayed | Rania Z. El-Shennawy | A.F Tolba
The red palm weevil (RPW) Rhynchophorus ferrugineus (Coleoptera: Curculionidae) is the most destructive pest of date palm Phoenix dactylifera L. in Middle East particularly in ArabGulf countries. Distribution of RPW infestations in relation to some factors was studied in date palm farms in Qatif Governorate, EasternSaudi Arabia. For these studies, 80 farms containing over 11000 date-palm trees were inspected. A scale for grading the infestation severity was developed. Numerical, but not statistical differences were in infestation levels with RPW, were found among farms due to their location (desert or oasis), irrigation system (dripping or flooding), intercropping (with or without) and pruning condition (pruned or unpruned). However, too small farms (less than 100 palm trees/farm) or too large farms (over 1000 trees) were highly infested while farms of 400-800 trees/farm were the least infested. Over 42% of infestations were concentrated at or below the soil surface. Light or surface infestations formed 45% while severe or deep infestations formed 19% of total infestations. Trees of 5-10 years old were the most infested while trees over 15 years were the least infested.
Mostrar más [+] Menos [-]EFFECT OF IRRIGATION WATER SALINITY LEVELS ON GROWTH, CHEM-ICAL COMPOSITION AND YIELD OF SOME NEW SWEET POTATO CULTI-VARS WHICH THEIR SOURCE IS TRUE SEEDS
2009
Two pot experiments were carried out during the summer seasons of 2006 and 2007 to investigate the effect of irrigation with diluted saline water; i.e., 10, 30 and 50% in addition to Tap water as a control on growth, chemical composition, yield and tuber quality of three new sweet potato cultivars (Minufiya 6/96, Minufiya 2/96 and Minufiya 171/96) as well as the local cultivar (Mabrouka). The obtained results revealed that, saline water at 10 and 30% levels stimulated growth of sweet potato plants represented by plant height, number of leaves and branches, dry weight of shoots as well as the contents of photosynthetic pigments, proline, total carbohydrates, N, P, K+ and Ca++ in sweet potato leaves were also increased. Moreover, total water content (TWC), bound water (BW), bound / free water ratio (BW/FW) and relative water content (RWC) increased under these conditions. All these parameters decreased at the level of 50% salinity. Yield and its quality significantly increased at saline water at 10% level. Also, chemical composition of tuber roots; i.e., total carbohydrates, soluble sugars, carotene, starch and dry matter contents were enhanced under these conditions. All previous parameters decreased with increasing saline water up to 50%. Saline water levels increased Na+ content in the leaves. As for the tested cultivars, generally Minufiya 6/96 had the best growth and yield, was more stable in the chemical components and its roots had the highest nutrients value under the control and salt stress conditions, followed by Minufiya 2/96 then Minufiya 171/96. The tuber roots yield of Mabrouka cultivar was completely depressed at 30 and 50% salinity levels. As for interaction between cultivars and salinity levels. The highest level of salinity (50%) lead to a significant decrease in all growth parameters, RWC, TWC, bound water (BW), bound water / free water (BW/FW), chemical composition, yield and its quality in all new tested cultivars. While, Mabrouka cultivar showed a significant decrease in these parameters under the all salinity levels. Accordingly, Minufiya 6/96 was the highest tolerant to the tested salinity stress, followed by Minufiya 2/96 and Minufiya 171/96. On the other hand, Mabrouka cultivar sensitive to salinity.
Mostrar más [+] Menos [-]EFFICACY OF SOIL SOLARIZATION AND DAZOMIT (98%) IN CONTROL OF ROOT-KNOT NEMATODE ON CUCUMBER UNDER THE OPEN FARMING CONDITIONS OF DEIR EZZOR, SYRIA
2009
Theimmediate and long term evaluating trails based on efficacy of soil solarization process and the pesticide Dazomit (98%) was worked out to control theroot-knot nematode on cucumber. The temperature rised significantly (4.0, 12.2, 13.3, 20.9)C° at the soil depths of (5,10,15,20) cm, respectively; when soil was covered with transparet plastic in July compared to nonsolarized soil (control). The results showed insignificant differences for the treatments combinations of soil solarization and the differences rates of Dazomit (98%) and the soil solarization alone in its ability in reducing numbers of theroot-knot nematode after one month of soil solarization and the treating with Dazomit (98%) reaching an efficacy ranged between 94-100% at the soil depth of 0-30cm. The results also indicated superior significancy of these treatments in preventing reforming the disease- causing aggregates of these nematode during the second season, with growth rates ranged between (2-5.8)% compared to(45-48.9)% at the end of first season, and the incidence was reduced with rates (96-98) % and the severity of infection rate (73-87)% at the end of season compared to (100)% in control treatment and indicated a high economic return (405%) for the solarization treatment alone compared to 5,18 and 83% in the three treatment combinations, respectively.
Mostrar más [+] Menos [-]MONITORING THE SEASONAL FLIGHT ACTIVITY OF STEM BORER MOTHS TO DETERMINE THE PROPER TIME FOR RELEASE TRICHOGRAMMA PARASITOID AT SUGARCANE FIELDS IN UPPER EGYPT
2009
The seasonal flight activity of both sugarcane stem borer moths Sesamia cretica Led. (Noctuidae: Lepidoptera) and Chilo agamemnon Bles. (Pyralidae: Lepidoptera)were monitored with Robinson light trap for two successive years 2005/2006 & 2006/ 2007 at El-Mattana Agricultural Research Station, Qena Governorate, to determine the proper time for releasing the egg-parasitoid, Trichogramma evanescens West. for biological control program to the two mentioned borers without any application with chemical pesticides. The obtained results showed that, the moths of the greater sugarcane stem borer, S. cretica had a main period of seasonal activity extended from spring to early summer (April to June) and had another four small peaks of seasonal activity at sugarcane fields occurred in April, June, July, and October. The small sugarcane stem borer moth, C. agamemnon had two main periods of seasonal activity at sugarcane fields. The first period extended from spring to early summer (March to June) and the moths probably recorded two broods during this period, whereas the second period was relatively smaller and occurred during July. Results of statistical analysis showed that, the combined effect of the three main weather factors (mean of min. & max. temperatures and %R.H.) two weeks earlier were responsible on the changes in the seasonal flight activity of S. cretica moths for 51.6% and 66.7% explained variance for the 1st and 2nd year, respectively. Also, these factors were responsible on the changes in the seasonal flight activity of C. agamemnon moths for 57.7% and 44.1% explained variance for 1st and 2nd year, respectively. So, it could be recommended that, the egg-parasitoid, Trichogramma evanescens releasing program must be started at mid- April for autumn and spring plantations, while for the next ratoons after two months from harvest and continued biweekly intervals to the end of June.
Mostrar más [+] Menos [-]FACTORS AFFECTING THE (PRODUCTION OF EXTRACELLULAR NEUTRAL PROTEASE) BY STREPTOMYCES MICROFLAVUS
2009
Saadia, M. Hassanein | Hala M. Rifaat | Osama Hamed El-Said | Souad A. Saleh | Manal S. M. Selim
In order to produce neutral protease from Streptomyces microflavus, it was cultivated in basal medium containing soluble starch, potassium nitrate, dipotassium hydrogen phosphate, magnesium sulphate, sodium chloride, calcium carbonate and ferrous sulphate. Protease production increased with decreasing the ratio of culture broth to vessel volume 1:5 and shaking at 150 rpm. Protease production was low when pH was < 5 or > 9. The productivity of protease decreased sharply when the incubation temperature increased from 30 to 450C. The maximum yield of protease was obtained at the third day of incubation. Soluble starch and yeast extract were the best carbon and nitrogen sources, respectively. Supplementation with calcium carbonate enhanced protease production. In addition, the dipotassium hydrogen phosphate was the best phosphorous source. Para chloromercuribenzoic acid and phenyl methylsulfonylfloride had significant inhibitory effect on protease production.
Mostrar más [+] Menos [-]TENDENCY OF CERTAIN PULSE SEEDS TO CALLOSOBRUCHUS MACULATUS (F.) AND CALLOSOBRUCHUS CHINENSIS (L.) INFESTATION
2009
The seeds of six different species of common pulses were examined as hosts of two bruchid beetles, Callosobruchus maculatus (F.) and C. chinensis L. under controlled conditions of 30±2ºC and 65±5% R.H. Deposited eggs, Hatched eggs, numbers and weights of emerged adults and also the total developmental period from the deposited eggs to adults emergence were estimated. Results obtained indicated thatcowpea seeds were the most favorable for feeding the two tested bruchid beetles, followed by faba bean seeds, while insect infestation was not observed on common bean and soybean seeds for either bruchid species.Results also revealedthat C.maculatus deposited more eggs on all tested leguminous seeds and gave more emerged adults with heavier weights than C. chinensis.
Mostrar más [+] Menos [-]ASSESSMENT OF THE ENTOMOPATHOGENIC FUNGUS BEAUVERIA BASSIANA SAUDI ARABIAN ISOLATE (B - SA3) AGAINST THE DEVELOPMENTAL STAGES OF THE RED PALM WEEVIL, RHYNOCHOPHORUS FERRUNGINEUS (OLIV.)
2009
The efficacy of the entomopathogenic fungus Beaveria bassiana Saudi Arabian isolate (B-SA3)was evaluated against the red palm weevil, Rynochophorus ferrungineus (Oliv.).The mentioned isolate was assessed on the different developmental stages of the red palm weevil through toxicity tests, i.e. determination of lethal concentration and lethal times to kill 50% of treated insects. The results showed that 8th instar larvae were the most tolerant followed by pupa to B.bassiana as their LC50 values were 3.75x 108 and 3.78x 107 conidia/ ml, respectively. Meanwhile, 4th instar larvae were the most susceptible to infection by B.bassiana (B-SA 3), as LC50 value was 3.25x 106 conidia/ ml, which proved insignificantly different to that determined in adult weevils, i.e. 4.18x 106 conidia /ml. Furthermore, LT50 values were very similar in these latter mentioned developmental stages in any considered concentration; meanwhile, LT50 was much longer in 8th instar larvae than the other considered instar and/or developmental stages. The fungus B. bassiana was most virulent to eggs of the red palm weevil as none of the eggs hatched following their treatment with any of the considered concentrations (ranging between 5x 109 to 5x105 conidia /ml). Moreover, germination viability of harvested conidia of B.bassiana stored at -4°C was insignificantly affected up to the 10th month storage period and was well above 90%. However, germination percentage of conidia then decreased to 70.27% after 16 months of storage. Also, the virulence of the stored conidia was tested after 1, 6, 12 and 16 months on adult red palm weevils, the LC50 values were 3.75x106, 4.66x106, 4.17x107 and 3.37x108 conidia/ ml, respectively. These results show that there was a significant decrease in the virulence of the tested fungus when the duration of storage period was more than 10 months.
Mostrar más [+] Menos [-]DISAPPEARANCE OF AZOXYSTROBIN, CYPRODINIL, FLUDIOXONIL, FENHEXAMID AND MYCLOBUTANIL IN STRAWBERRY FRUITS UNDER FIELD CONDITIONS
2009
A field experiment was carried out at Nubariah region Alexandria desert road located at 120 Km from Cairo, (Egypt) during 2005-2006 to study the degradation rates of five fungicides azoxystrobin, cyprodinil, fludioxonil, fenhexamid, and myclobu-tanil in strawberry fruits after application with their recommended rates under field conditions. The samples were collected in successive intervals after spraying and transported to Bioforsk refer-ence Lab, Ǻs, Norway for analysis by GC/MS. The fungicide residues on strawberry showed different degradation rates after treatment, with first-order kinetics. Half-lives (t0.5) were 1.92, 4.99, 3.68, 6.02 and 5.17 days for azoxystrobin, cyprodinil, fludioxonil, fenhexamid and myclobutanil, respectively.
Mostrar más [+] Menos [-]STUDIES ON NEEM SEED KERNEL EXTRACTS AS OVIPOSITION DETERRENTS AND OVICIDAL COMPOUNDS FOR THE COTTON LEAF WORM MOTHS, Spodoptera littoralis (Boisd.)
2009
H.A Gomaa
Mated female moth of the cotton leafworm, S. littoralis laid a total number of 1564.22 eggs during its whole life. In a free choice test, treating N. oleander leaves (as an oviposition site) with an aqueous extracts of neem seed kernel solutions extracted by different organic solvents reduced the number of deposited eggs on it. The lowest number of eggs was recorded when methanol was used for extraction, followed by chloroform, and the highest was, however, obtained after using benzene, butanol and ethyl acetate. The number of deposited eggs decreased as the concentration of any tested neem extract increased to reach the minimum at 0.2%. This means that the most deterred neem seed kernel extract is that which extracted with methanol at the concentration of 0.2%.Hatchability percentage of S. littoralis eggs greatly affected by the type of organic solvents used for neem extraction and the concentration of each extract on treated N. oleander leaves. The lowest hatchability was recorded after using methanol, followed by chloroform.On the other hand, an increase in neem seed kernel extract concentration caused an obvious decrease in egg hatchability.
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