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EFFICACY OF CHEMICAL AND BIOLOGICAL TREATMENTS FOR CONTROLLING SOIL-BORNE PATHOGENS OF SOYBEAN
2009
Ahmed Awad Altalb
Several soil-borne fungal pathogens attack soybean plants, causing seedling damping-off and root rot diseases, in Egypt. Isolation trials from rooted rots of soybean, collected from various locations at Gharbiya, Kafr El-Sheikh and Minufiya governorates, revealed that Rhizoctonia solani, Fusarium solani and Macrophomina phaseolina were the most virulent and predominant pathogens. All the tested fungicides significantly reduced linear growth of the tested pathogens. Three known bioagents i.e. Trichoderma harzianum, T. hamatum and Bacillus subtilis were tested against such pathogens, and revealed remarkable effect in reducing mycelial growth on PDA medium. T. hamatum, mainly, grew over the mycelium of the tested pathogens. Under greenhouse conditions, both the fungicides and antagonists gave significant reductions of root rot severity, but fungicides were more effective than biocontrol agents in reducing the disease. Application of the selective antagonists and fungicides significantly decreased soybean root rot than untreated check, in naturally pathogen- infested fields. Plant growth and activity of nitrogenase enzyme were enhanced greatly, when the fungicides were applied compared with antagonists treatments.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]RESPONSE OF TWO SOYBEAN CULTIVARS AND THE ASSOCIATED WEEDS TO SOME AGRONOMIC FACTORS UNDER NEWLY RECLAIMED SOIL
2009
Individual and integrated effects of three weed control treatments H [weedy control (H1); Butralin (H2) and manual twice hoeing (H3)] , three hill spacing , D [10 (D1), 15 (D2) and 20 cm (D3)] and two soybean varieties, V [ Giza 111 (V1) and Giza 21 (V2)] on dry matter (DM) of associated weeds, growth traits and parameters, nutrients uptake and seed yield, were the intended aim of the present study. To achieve this aim, split- split plot arrangement was used, where tested variables; H, D and V were allocated in main-, sub- and sub-sub plot, respectively, at newly reclaimed soil of the experimental farm "Demo" of Fac. Agric., Fayoum Univ., during 2006 and 2007 summer seasons. The obtained results could be summarized as follows: Dry weight of weeds were deppressed by twice manual hoeing, dense planting, chemical control and the interaction of H2D2V2 in the first sample and H3 V1 in the second sample.Maximum values of soybean height, number of branches, LA and LAI were obtained by H2 or H3 depending on the sample as well as the studied variety. Soybean density had a significant effect on plant growth (height, DM and LA). In addition CGR and NAR as well as N, P, and K were affected by H3 and H2. Several dual and triointeractions significantly affected the growth traits. Manual hoeing, H3 (1490 kg/fed) out yielded Butralin treatment, H2 (1000kg/fed) and both surpassed the weedy control one, H1 (530 kg/fed). Closest spacing, D1 (1080 kg) followed by intermediate one, D2 (1060 kg) produced markedly by higher seed yield/fed that of the widest spacing (890 kg). V2 (1080kg) out yielded V1 (940 kg/fed). H3 D1 (1840), D2 V2 (1500) and H3D2 (1260) as well as H3D1V2 (1890 kg/fed) were the most effective interactions on soybean yield. The obtained results revealed that, in such newly reclaimed land, the maximum yield with improved quality of soybean could be obtained from Giza 21 planted in closed spacing (10cm) and treated with manual hoeing twice.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]SOME FACTORS AFFECTING THE SUSCEPTIBILITY OF FOUR STORED GARLIC CULTIVARS TO INFESTATION WITH CRYPTOBLABES GNIDIELLA MILLIERE
2009
L.A. Youssef | M.S . Abdel-Wahaed | A.S. Kassab | M.M.E. Saleh
The honey dew moth Cryptoblabes gnidiella Milliere is one of the most important insect pests of stored garlic. Data revealed that, Egyptian (Baladi) cultivar was the least susceptible to attacke by this insect . After four months of storage, the infestation percentages were 21.68% for Egyptian (Balady) cultivar as compared to 32.39% for Sids 40, 44.88% for American and 70.99% for Chinese cultivar. The oil content of the four garlic cultivars were measured along four months of storage. Data showed that the four cultivars were differed significantly in this respect. The highest weight of volatile oils, 436.8 mg/100g was fined in the Egyptian cultivar whereas the Chinese cultivar had 340.6 mg/100g. The correlation coefficients “r” values showed highly significant and negative relationship between infestation percentages and volatile oils weight (mg) . The main components of the volatile oils of the tested four garlic cultivars were separated by GC- MS analysis. Nine sulfur compounds were separated and identified, the major compound was Diallyl trisulfide (i.e. 49.82, 46.23, 46.17 and 44.89%) for Egyptian, Sids 40, Chinese and American cultivars, respectively. Allyl methyl trisulfide ranged from 11.40 to 23.15%. On the other hand percentage of total soluble solids (TSS%) for the four cultivars were almost the same trend during the storage period extended for four months or slightly increased. These data indicate the importance of the type and quantity of volatile oils and its component in protection of stored garlic from infestation by C. gnidiella.
显示更多 [+] 显示较少 [-]REPRODUCTIVE TOXICITY OF BACILLUS THURINGIENSIS BIO-PESTICIDE IN MALE ALBINO RATS
2009
The present study is a trial to investigate the toxic effects of the bio-pesticide Bacillus thuringiensis (Bt) on male reproductive system of rats. Rats received dietary doses each approximately equivalent to 1/10 or 1/100 of the LD50 value of the Bt bio-pesticide (Agerin) for 90 consecutive days. Sex organs weight, semen picture, concentrations of the hormones [i.e., testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH)], and histopathological changes in testes were the criteria used to evaluate the reproductive toxicity on the treated rats. Btat the higher dose caused a significant decrease in the weight of testes and seminal vesicles as compared with control. Both Bt doses decreased sperm count associated with an increase in the morphologically abnormal spermatozoa; however sperm motility was significantly decreased in treated rats with the higher dose only. The concentration of serum testosterone was significantly reduced in both treated groups; however LH and FSH levels were significantly reduced in treated rats with the higher dose. Histopathological examination of Agerin-treated male rat's testes revealed that both Bt doses caused testicular degeneration in a dose-dependent manner. In conclusion, Agerin may decreases fertility in adult male rats by affecting the concentrations of pituitary gonadotrophins, testosterone and thus subsequent spermatogenic impairment
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]CHANGES OF SOME SOIL PHYSICAL AND HYDROPHYSICAL CHARACTERISTICS IN RESPONSE TO DIFFERENT SPRINKLER TYPES AND NOZZLE SIZES
2009
Walaa El-Shalakany | M.O El-Zakaziky | A.M. El-Araby | E.A. El-Sahhar | Y.E Arafa
Soil characteristics' degradation had been considered as one of the most important problems that face the agricultural development processes under arid and semi-arid conditions due to non-suitability of the applied technologies and techniques, attributed to management considerations. Consequently, higher crop yield and quality reduction had been occurred due to the degradation of the plant healthy media (soil). Therefore, the goal of this investigation was to monitor the change detection of some soil physical and hydrophysical characteristics under sprinkler irrigated agriculture. However, the terminal objectives were to evaluate and monitor some soil characteristics changes (soil bulk density, hydraulic conductivity and soil penetration resistance) under different mode of action of sprinkler types (rotating and impact sprinkler) and corresponding nozzle sizes (small and large sizes). Hereby, field experiments were carried out for two seasons (2006 and 2007) in the Desert Experimental Farm of Faculty of Agriculture, AinShamsUniversity which is located at El-Bustan region, Behaira Governorate. Results revealed that soil characteristics were highly affected with the sprinkler mode of action and corresponding nozzle sizes. However, a power function proportion of soil penetration resistance with respect to applied rotating and impact sprinkler types and corresponding small and large nozzle sizes, had been observed and analyzed. Therefore, data analysis speculated that, selection of the appropriate sprinkler types under diverse field conditions and situations such as: crop type and design criteria of sprinkler irrigation systems, have to be considered for good agricultural development processes under Egyptian newly reclaimed regions.
显示更多 [+] 显示较少 [-]RELATIVE IMPORTANCE OF FIBER PROPERTIES AFFECTING YARN HAIRINESS IN SOME EGYPTIAN COTTON VARIETIES
2009
Kh.M.M Hussein | M.H . Mahmoud | A.A . Hassan
undesirable, depending on the application for which the yarn is being used. Hairy yarns provide good heat retention and a softer hand (feel) for finished fabrics, and except for a few special cases, when it is an excessive degree of hairiness, yarn hairiness is an undesirable property in yarn and can cause serious problems in both yarn production and in subsequent textile processes. This search was carried out to investigate the most important fiber properties i.e. short fiber content (SFC w %), maturity ratio, micronaire value, uniformity index (UI %), fiber length (UHM) and fiber strength (g/tex) which correlated with yarn hairiness and also their relative contributions in yarn hairiness under study by using four Egyptian cotton varieties during season 2008, namely; Giza88, Giza86, Giza80 and Giza90 spun into carded ring and compact yarns at twist multiplier 3.6 and two into counts according to the following: ring yarns were processed to carded yarns Ne 50 and 60. Compact yarns were also processed to carded yarns at the same counts. The most important results were: 1- Yarns manufactured by the carded ring spinning frame are characterized by higher hairiness mean values in all studied varieties in comparison with those of carded compact frame. 2- The correlation coefficients have positive signs and are very high between hairiness in yarns and short fiber content (SFC w %), on the contrary the correlation coefficients have negative signs being high or very high between maturity ratio, micronaire value, uniformity index (UI %), fiber length (UHM) and fiber strength (g/tex) and yarn hairiness in all varieties. 3- Stepwise regression procedure was employed to determine the most effective independent variables which make the maximum contributions to the coefficient of determination (R²). The rate of improvement in yarn hairiness index due to decrease short fiber content (the larger the share of fibers in the shorter length the higher is the hairiness index), increase fiber strength (more mature fiber) and increasing fiber length (the larger the share of the fibers in longer length the lower is the hairiness index
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