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Ragab Abdelmohsen E-Mergawi ;Khalid Naser Al-Redhaiman ;Hussein F. Abouziena 《农业科学与技术》2014,(7):597-604
The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing antioxidant power （FRAP）, total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels （20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato） and four nitrogen sources （calcium nitrate, ammonium sulphate, ammonium nitrate and urea）. The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents. 相似文献
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During 2010, yellowing symptoms were frequently observed in cultivated squash fields in Egypt. A total of 717 symptomatic
squash leaf samples were collected from four regions where squash cultivation is of economic importance for the country: Kafrelsheikh,
El-Behira, El-Sharkia and El-Ismailia. Serological analysis showed that 95.6% of the symptomatic squash samples were infected
by Cucurbit aphid-borne yellows virus (CABYV), and visual estimation of the incidence of yellowing symptoms suggested a very high incidence of CABYV in the fields.
Twelve CABYV isolates were characterized by sequencing two regions of the viral genome, open reading frame (ORF) 3 and ORFs
4/5. Overall, Egyptian isolates were very similar among them, and had higher similarity values with a French than with a Chinese
isolate. The average nucleotide diversity for ORF 3 was significantly higher than for the other two regions, indicating that
variability is not evenly distributed along the viral genome. The ratios between nucleotide diversity values in non-synonymous
(d
N
) and synonymous (d
S) positions (d
N
/d
S) for each ORF showed that the three ORFs are evolving under different pressures, although predominantly under purifying selection.
Phylogenetic analyses revealed that these Egyptian isolates, with only one exception, shared the same clade with a French
isolate. Moreover, these analyses suggested that Egyptian isolates belong to the Mediterranean group described previously. 相似文献
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Azadeh Ghaneie Rahim Mehrabi Naser Safaie Masoud Abrinbana Abbas Saidi Mostafa Aghaee 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(2):191-202
Septoria tritici blotch (STB), caused by Mycosphaerella graminicola has recently become one of the devastating diseases in Iran causing significant yield losses on most commercial bread and
durum wheat cultivars. Iran is located in the Fertile Crescent, a region where wheat was historically domesticated; and, thus,
landraces derived from this region are of considerable global interest for identification of new sources of resistance to
various stresses. Here, we report on the resistance responses of 45 tetraploid wheat landraces collected from different provinces
of Iran to eight M. graminicola isolates. In total 138 isolate-specific resistances were found among all interactions (n = 360). The highest number of specific resistances (30 out of 32 interactions) was found in wheat landraces collected from
West Azarbaijan. In contrast, all landraces from Kordestan were highly susceptible to M. graminicola isolates and only one isolate-specific resistance was identified among 106 isolate-wheat interactions. Kermanshah landraces
showed the highest resistance variation against different isolates. About 57 isolate-specific resistances were identified
among 104 interactions. Ilam landraces were highly resistant to STB as 28 specific resistances were observed among 32 interactions.
Markazi (n = 2) and Sistan-Baluchestan (n = 1) were susceptible to all isolates tested. Landraces from Lorestan were generally susceptible to isolates tested as 26
susceptible responses were observed out of 32 interactions. Our results indicate that landraces collected from the Fertile
Crescent region may possess diverse effective resistance genes or valuable broad spectrum resistance genes, and that their
identification is of interest and can be exploited in breeding programs. 相似文献
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Somayeh Keypour Hossein Riahi Mohammad Reza Asef Jafar Abdollahzadeh Ali borhani Naser Safaie 《Forest Pathology》2020,50(4)
The genus Ganoderma Karst. has broad‐spectrum usage in biotechnology, medicine and the food industry. The complexity of the morphology within species has led to uncertain identification in the past, but recent advancements in molecular identification methods have provided scientists with the opportunity to better understand the taxonomy of the species. The present study attempts for the first time to elucidate the distinctiveness of the Ganoderma species growing in Iran concerning those elsewhere in the world based on mitochondrial small subunit ribosomal DNA (mtSSU rDNA) and internal transcribed spacer (ITS) sequence data. The results disclosed that the G. lucidum Karst. samples collected in Iran are more similar to the European Ganoderma species than to the Asian (Chinese) one used in this study. 相似文献
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Semen characteristics of rainbow trout (Oncorhynchus mykiss) following diets containing different vegetable fatty acid levels 
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下载免费PDF全文 M Hajiahmadian K Sarvi Moghanlou N Agh F Farrokhi Ardabili 《Reproduction in domestic animals》2016,51(6):979-984
Brood fish nutrition is an important factor susceptible to affect not only fecundity and gametogenesis but also gamete quality. In this study, we investigated the effects of altering dietary vegetable fatty acid content on semen quality (i.e. motility, density and seminal plasma composition), fertilizing ability and also blood testosterone (T) concentration in rainbow trout (Oncorhynchus mykiss). Fish were fed a commercial diet and ten formulated diets with similar proximate compositions but different levels of vegetable fatty acids (highly unsaturated fatty acids (HUFA): monounsaturated fatty acids (MUFA); HUFA: polyunsaturated fatty acids (PUFA); and HUFA: saturated fatty acids (SFA) ratios). Fish fed with HUFA: MUFA = 0.0 and HUFA: SFA = 0.25 ratios had the highest semen motility percentage and duration. However, the highest semen concentration and semenatocrit were observed in HUFA: SFA = 0.0 and HUFA: PUFA = 0.37 ratios. There was a significant difference in terms of K+ ion among diets supplemented with HUFA: PUFA = 0.0, HUFA: PUFA = 0.37 and HUFA: MUFA = 0.16 ratios (p < .05). Furthermore, Na+ ion showed significant difference between control group and diet supplemented with HUFA: PUFA = 0.0 (p < .05). Among the biochemical parameters, total protein showed a significant difference between HUFA: MUFA = 0.16 and HUFA: PUFA = 0.37 ratios (p < .05). No significant differences in fertilization ability and blood T concentration were found among dietary treatments (p > .05). In addition, the present data suggest that dietary fatty acid levels could affect semen quality but not fertilization ability in O. mykiss. 相似文献
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Optimal dietary carbohydrate‐to‐lipid ratios for silvery‐black porgy (Sparidentex hasta) juveniles 下载免费PDF全文
下载免费PDF全文 M. Torfi Mozanzadeh V. Yavari J.G. Marammazi N. Agh E. Gisbert 《Aquaculture Nutrition》2017,23(3):470-483
Four isonitrogenous diets containing different carbohydrate:lipid (CHO:L) ratios (0.3, 0.6, 1.1 and 1.8) were tested in triplicate groups (16 fish per replicate) of silvery‐black porgy juveniles for 8 weeks. Growth performance was not affected by different dietary CHO:L ratios (P > 0.05); however, the viscerosomatic index, the intraperitoneal fat, whole‐body lipid, energy and n‐3 long chain polyunsaturated fatty acids levels increased with decreasing dietary CHO:L ratios (P < 0.05). Fish fed with 1.8 CHO:L diet had the lowest apparent digestibility coefficients of protein and lipid, as well as the lowest plasma haemolytic and lysozyme activities (P < 0.05). Red blood cell counts and plasma glucose levels were higher in fish fed with 1.1 and 1.8 CHO:L ratio diets than in the other groups (P < 0.05). Plasma alkaline phosphatase and alanine aminotransferase, as well as the level of lipid peroxidation and total antioxidant capacity in the liver and plasma increased as dietary CHO:L ratios decreased (P < 0.05). The results of the current study indicated that the diets with CHO:L ratios between 0.6 and 1.1 are optimal for silvery‐black porgy, whereas higher ratios may result in hyperglycaemia and immune suppression, and lower CHO:L ratios may lead to oxidative stress and liver dysfunction. 相似文献
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Reproductive performance of fairy shrimp Branchinecta orientalis (G. O. Sars 1901) (Crustacea: Anostraca), fed with effluent of rainbow trout Oncorhynchus mykiss (Walbaum 1792) ponds 下载免费PDF全文
下载免费PDF全文 N. Pormehr N. Agh L. Beladjal B. Atashbar G. Van Stappen 《Aquaculture Nutrition》2018,24(5):1502-1508
Aquaculture production is predicted to increase sharply. In this regard, live feed plays a crucial role in the larval phase of many aquaculture organisms. Hence, a persistent concern in aquaculture is to find low‐cost and eco‐friendly feed sources to culture live feed organisms. Branchinecta orientalis (G. O. Sars 1901), a fresh/brackish water fairy shrimp, was reared using effluent from rainbow trout Oncorhynchus mykiss (Walbaum 1792) ponds, either fresh but supplemented with two species of microalgae, Scenedesmus sp. and Haematococcus sp., or non‐supplemented but after “ageing” of the culture medium. The feeding experiment was designed at a density of 100 individuals L?1 in 2‐L vessels. The results indicated that differences between final length, survival and most reproductive parameters of the treatment with aged medium and the treatment using fresh medium supplemented with Scenedesmus sp. were non‐significant (p > .05). Better results were obtained for a number of reproductive parameters in the treatment supplemented with Haematococcus sp. Thus, for intensive resting egg production of B. orientalis, microalgae can be replaced by aged non‐supplemented effluent from trout ponds as a nutrient‐rich feed source. This consequently can reduce drainage of nutrients into the environment and thus decrease aquatic pollution. 相似文献