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41.
In this study, the effect of maternal age on prepupae diapause of progeny in sexual (Wolbachia free) and asexual (Wolbachia infected) Trichogramma brassicae was studied at two temperatures. Maternal generation (G1) of both populations was reared at 10L:14D photoperiod, 14 and 20 °C, separately. Mated females from G1 were supplied with eggs of Ephestia kuehniella, each 48 h from one day after emergence to death. The tendency to diapause in progeny (G2) was determined by rearing at 10 °C. According to the results, reproductive modes, maternal temperature and age have significant effect on the mean number of eggs laid by G1 and the diapause percentage of G2. Offspring whose maternal generation was reared at 20 °C had higher diapause percentage than those reared at 14 °C. Diapause percentage in sexual population was higher than the asexual, which demonstrates a negative effect of Wolbachia on this process. Wolbachia infection modifies the effect of maternal age on the diapause percentage in the offspring at 20 °C but not at 14 °C. The result can be due to lower Wolbachia density at 14 °C and greater Wolbachia density at 20 °C. 相似文献
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Ghasem Ali Parad Masoud Tabari Kouchaksaraei Gustavo Gabriel Striker Seyed Ehsan Sadati Kazem Nourmohammadi 《Scandinavian Journal of Forest Research》2016,31(5):458-466
Tolerance to flooding is crucial when thinking in promissory species for restoration of ecosystems prone to suffer soil water excess. In this study, we tested the flooding tolerance of two-years-old seedlings of Chestnut-leaved oak (Quercus castaneifolia C.A.Mey.) to determine whether it can be recommended for use in wetland restoration programs. Seedlings of Q. castaneifolia were subjected to three treatments: (1) control (C), (2) flooding for 60 days followed by a 42-day recovery period (F?+?R) and (3) continuous flooding for 102 days (F). Physiological performance, plant morphological changes and biomass accumulation were assessed. Results showed that, although net photosynthetic rates, stomatal conductance and transpiration decreased with prolonged flooding, when flood waters were removed, plants were able to recover their physiological activity (49–80% compared to controls). By contrast, when plants were continually flooded, their physiological activity decreased as well as the leaves experienced precocious senescence and wilting. Biomass responses paralleled physiological responses: leaf and root biomass were 42–49% higher under F?+?R treatment than under continuous flooding, and all plants under the F?+?R survived. Therefore, Q. castaneifolia appears as a promising species to be further studied when thinking re-vegetation of riverine areas and other temporarily flooded wetlands. 相似文献
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Zabihallah Bahmani Masoud Rezaei Seyed Vali Hosseini Seyed Fakhreddin Hosseini Alireza Alishahi Mehraj Ahmad 《Journal Of Aquatic Food Product Technology》2013,22(6):542-551
Research has shown that fresh fish is an extremely perishable food as compared to other food commodities. In this study, quality deterioration during storage of golden grey mullet (GGM) iced for 0, 6, and 12 h after landing was monitored. Microbiological indices (total viable count, TVC; psychrophilic counts, PTC; lactic acid bacteria, LAB; and Enterobacteriaceae counts, EBC), chemical parameters (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA; and free fatty acids, FFA) values increased over the preicing duration. Delayed icing did not lead to significant increases (p > 0.05) in TVC, PTC, LAB, and EBC throughout the period of storage. All chemical indices increased during storage (p < 0.05). This study showed that sensorial analysis of GGM correlated well with microbiological analysis. Results of this study based on the microbiological and raw fish sensorial data indicated that the shelf life of GGM stored in ice immediately after catch was approximately 10–11 days, while the 6- and 12-h delays in icing shortened the shelf life to approximately 6–7 and 2–3 days, respectively. 相似文献
46.
Parastoo Pourashouri Bahareh Shabanpour Seyed Hadi Razavi Seid Mahdi Jafari Ali Shabani Santiago P. Aubourg 《Journal Of Aquatic Food Product Technology》2013,22(6):567-578
Multilayer microencapsulation of fish oil was evaluated by using fish gelatin (treated with or without microbial transglutaminase [MTGase]), chitosan, and maltodextrin for its ability to control lipid oxidation. This study showed that a mixture containing gelatin and maltodextrin obtained the highest percentage of core release. The oxidative stability of the formulated mixtures and the bulk oils was investigated during a period of 60 days. The peroxide value (PV) was assessed as a parameter for primary oxidation products, and p-anisidine (p-AV) and thiobarbituric acid reactive sub-stances (TBARS) was used to analyze secondary oxidation compounds. Observation of oxidation products showed that combinations of gelatin and maltodextrin made by adding MTGase and a mixture of gelatin and chitosan were able to increase the oxidative stability, and increases in PV and p-AV and TBARS were found for all oils. 相似文献
47.
Effect of dietary tryptophan (TRP) on copper toxicity was investigated in common carp, Cyprinus carpio. Fish were randomly distributed into two triplicate treatments (control and TRP) and fed control (TRP?=?3.1?g?kg(-1)) or TRP (TRP?=?8.1?g?kg(-1)) diets over a 2-week period. Then, both treatments were subjected to 10?mg?l(-1) copper sulfate over a 7-day period. Mortality and serum cortisol, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), sodium, potassium, and chloride levels were recorded at 0, 24, 72, 120, and 168?h post-copper exposure. There was no mortality in the TRP group, whereas the control group mortality was started at 120?h post-copper exposure (21.7?±?7.6?%) and reached 61.7?±?10.4?% at the end of the experiment. Cortisol, glucose, ALT, and AST levels significantly (P?0.05) increased after copper exposure in both groups; however, the control group showed significantly higher levels than the TRP group. In both groups, sodium decreased after copper exposure and did not return to the pre-exposure values. Potassium levels significantly increased 24?h post-copper exposure in both groups and remained significantly elevated in the control group at 72?h, when fell to the pre-exposure values in the TRP group. No significant changes were observed in the chloride levels in any groups. It is concluded that dietary TRP is capable to increase common carp tolerance to copper toxicity via mitigating copper-induced stress rather than restoring gill dysfunction and hydromineral imbalance. 相似文献
48.
Lactococcosis, a significant emerging disease of fish caused by Lactococcus garvieae, has become one of the devastating problems due to its serious economic damage in aquaculture. The aim of this study was to isolate and characterize a lytic phage infecting L. garvieae as a potential bioagent for the treatment of lactococcosis. In this regard, one strain of L. garvieae was isolated from diseased rainbow trout, and then, following biochemical and molecular identifications, its specific phage, WWP-1, which was able to destroy L. garvieae cells through the lytic cycle, was isolated from a municipal wastewater sample. Transmission electron microscope revealed that the isolated phage possesses an icosahedral head and a non-contractile short tail, resembled to members of the family Podoviridae. Moreover, phage WWP-1 represented optimal antibacterial activity at temperatures ranging from 15 to 30 °C, suggesting that it could be very effective at rainbow trout rearing temperature. Restriction profile analysis revealed that NdeI can digest WWP-1 genome while EcoRI, EcoRV, and BamHI were incapable of cutting its DNA. According to the in vivo experiment result, WWP-1 could decrease mortality rate of infected rainbow trout in aquaculture. The results suggest that this naturally occurring bacteriophage could be considered as a promising agent to control the disease caused by L. garvieae strains in rainbow trout rearing. 相似文献
49.
Isa Esfandiarpour-Borujeni Seyed Javad Hosseinifard Hossein Shirani Maryam Zeinadini Ali Asghar Besalatpour 《Communications in Soil Science and Plant Analysis》2018,49(12):1474-1490
The main objective of this study was to evaluate the potential use of a hybrid Genetic Algorithm-Artificial Neural Network (GA–ANN) method for predicting pistachio yield and for identifying the determinant factors affecting pistachio yield in Rafsanjan region, Iran. A total of 142 pistachio orchards were selected randomly and soil samples were taken at three depths. Besides, water samples and leaves from branches without fruit were taken in each sampling point. Management information and pistachio yields were achieved by completing a questionnaire. Primarily, 58 variables affecting pistachio yield were measured, and then 26 out of them were selected by minimizing mean square error (MSE) using a feature selection (FS) method. The results showed that the accuracy of the method was acceptable. Furthermore, the sensitivity analysis showed that the main determinant features affecting the pistachio yield were the irrigation water amount, leaf phosphorus, soil soluble magnesium, electrical conductivity (EC), and leaf nitrogen. 相似文献
50.
Edris Shabani Sahebali Bolandnazar Seyed Jalal Tabatabaei Nosratollah Najafi Saeedeh Alizadeh-Salteh Youssef Rouphael 《Journal of plant nutrition》2018,41(13):1662-1673
A greenhouse experiment was conducted to assess the effects of magnetic field, arbuscular mycorrhizal fungi (AMF), and phosphorus (P) concentration in the nutrient solution (0, 5, 10, 20, or 40 mg L?1) on the mobility and accumulation of P in soil and plant tissues of basil (Ocimum basilicum L.). The experiment was designed as a factorial combination and treatments were arranged in a completely randomized design with four replicates. Magnetic field increased water-soluble P in the soil and P concentration in plant shoot by 30.0% and 13.0%, respectively, in comparison to the control. The application of magnetic field and inoculation of AMF at 10 mg P L?1 increased the P translocation efficiency by 23.3% and 17.8%, respectively. Overall, our results demonstrated that the use of magnetic field and AMF could be an effective tool for enhancing of uptake and movement efficiency of P even at low concentrations. 相似文献