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Zinc and manganese sorption behavior by natural zeolite and bentonite
2011
Iskander, A.L. | Khald, E.M. | Sheta, A.S.
Understanding the sorption process in natural zeolite and bentonite is necessary for effective utilization of these minerals as nutrient adsorbents and on the other side for controlling release of plant nutrients. This research was undertaken to characterize the ability of natural zeolite and bentonite minerals to adsorb and release zinc and manganese. The potentials for sorption of these ions were evaluated by applying the Langmuir and Freundlich equations. The results showed that Langmuir constant (maximum adsorption (b mmol kg-1)) of both Zn and Mn were for bentonite zeolite While the [binding strength values (k in L.mmol1 for zeolite bentonite Zn in case of zeolite showed the lowest desorbed percentage particularly at high levels of sorbed Zn. Only, 74.7 % is readily extractable by DTPA after three successive extractions leaving, 25.3 % Zn retained by the mineral. In case of bentonite, 82.26 % of sorbed Zn is readily extractable by DTPA after three successive extractions leaving, 17.74 % Zn retained by the mineral. In case of Mn, 84.63% of Mn sorbed by zeolite is readily extractable by DTPA after three successive extractions leaving, 15.37% Mn retained by the mineral. In case of bentonite, 89.79 % of adsorbed Mn is readily extractable by DTPA after three successive extractions leaving, 10.21 % Mn retained by the mineral. This finding may reflect clearly the possibility of using natural zeolite and bentonite as a slow release fertilizer for Zn and Mn and on the other hand preventing soil pollution with heavy metals.
Показать больше [+] Меньше [-]Study of genetic relationship between some olive varieties in gellin gene bank
2011
Moustaf, N. | Hamed, F. | Lawand, S.
Olive tree (Olea europaea L.) is one of the most important fruit trees, there is a lot of varieties with the possibility of mislabeling, homogenouses and synonyms, which makes major troubles when having plant material for propagation and breeding programs. In this search, 12 olive varieties (Maw! Istanbul!, Khilkhali Khishen, Dan, Mniekri, Adkam, Doaibli, Mot, Khilkhali Saghir, Karamani Modabal, Mawi abo Shokeh, Sourani, and Abo Shokeh), cultivated in ACSAD Gene bank in Gellin, were characterized by ISSR molecular markers to determine the relationship between these varieties. Depending on quantitive traits the results indicated that these varieties are so close to each other's, ranged from 60% and 85%. It was noticed that Mneikri was apart from the other varieties in its traits, (polymorphic rate was 92.94%).
Показать больше [+] Меньше [-]Effect of harvesting dates on the yield and quality of some flax genotypes
2010
El-Kady, E. | Salama, A.S. | Abd-El-Fattah, A.A.
Two field experiments were conducted during the two successive seasons 2007/2008 and 2008/2009 at Sakha Agric. Res. Station, Kafr ElSheikh Governorate to study the effect of four harvesting dates i.e. 135, 145, 155 and 165 days after sowing on yield and its quality of six flax genotypes namely, Sakhal, Sakha 2, Sakha 3 and Giza 9 varieties and two new promising strains (strain 16 and strain 22). This study was laid out in a split-plot design, with four replications, the main plots were allocated to the six flax genotypes, whereas, the sub-plots contained the harvesting dates. The obtained results could be summarized as follow: Sakha 3 and Giza 9 varieties gave the highest means for technical length, fiber yield/plant as well as per fed., fiber length, fiber percentage, fiber strength, fiber fineness, germination % and crude protein %, whereas strain 22 (yellow seed) surpassed the other flax genotypes which produced the highest values for No. of seeds/plants, seed yield/fed., oil content and oil yield/fed. The harvest date of 155 days after sowing showed significant increases in stem diameter, straw yield/plant as well as per fed. fiber yield and its quality and crude protein % compared to the other three dates (135, 145 and 165 days after sowing). However, delayed harvesting date to 165 days after sowing recorded significant increase in technical length, upper branching zone length, seed yield and its related characters, germination %, seedling vigour, seed index, volume of 1000 seed,'oil content and oil yield/fed. The interactions among the studied factors had significant effects on straw yield/fed., No. of capsules/plants, fiber strength and germination % in the first season of study, while the characters of the upper branching zone length, seed yield/fed., oil yield/fed., fiber length and oil content in both seasons.
Показать больше [+] Меньше [-]Effect of treatment on the nutritive value and residues of some synthetic pesticides in fresh bolti fish
2010
Ahmed, N.S. | El-Saad, El.O.
Fresh Bolti -fish (Tilpia nilotica) collected randomly from 9 different markets in Ismailia Governorate for evaluation the effect of grilled fish by the method used in grillrooms and houses on the concentration of pesticide residues found and the nutritive value. Results revealed that decrease in the estimated parameters i.e. moisture, crude protein, fat and ash by grilling, this decrease were 6.07, 2.63, 4.07 and 1.56%, respectively. On the contrary, carbohydrates behaved another behavior that there was an obvious increase ranged from 1.98% to 2.92%. Fresh and grilled fish were analyzed to detect 12 organochlorine (OC) and 7 synthetic pyrethroid (SP) pesticides with a mean level on a lipid basis. Gas Liquid Chromatography equipped with Electron Capture Detector GC-ECD was used to detect the contamination in the samples. The results showed that p,p'-DDE isomer was dominated over the other isomers in all analyzed fish samples, followed by q-isomer of hexachlorocyclohexane. The concentrations of OC residues were higher than SP pesticides in all fish muscles. Also, the fresh fish muscle recorded higher concentrations of the evaluated pesticides than the grilled one.
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