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11.
Low efficiency of somatic embryo maturation, germination, and conversion to plantlets is a major problem in many species including J. regia L. Germination efficiency of somatic embryos is very low in walnut. In this study, effects of two carbohydrate sources, sucrose and maltose (each at 3% and 6%), and two kinds of PEG (4000 and 6000) (each at four levels of 1.5%, 3%, 5% and 7.5%) on maturation and germination of walnut embryos were tested. The number of somatic embryos increased conspicuously on medium containing PEG. Furthermore, higher levels of PEG-4000 (7.5%) could remarkably enhance the morphogenesis of somatic embryos and the number of embryos produced. PEG-4000 stimulated somatic embryo maturation of walnut. This stimulatory effect was dependent on the carbohydrate source used. Sucrose in combination with PEG-4000 produced 50% of cotyledonary and normal somatic embryos. Different concentrations of PEG were effective on the number of embryos with a shoot meristem. PEG-4000 7.5% and sucrose 3.0% produced the highest rate (50.0%) of normal shooting embryos. However, PEG (4000, 6000) and maltose caused an unfavorable effect and increased the frequency of abnormal shaped somatic embryos.  相似文献   
12.
Background: Previous studies have shown that some cytokines have protective effects on cartilage in joint diseases. In the current study, effects of IL-4 against morphological changes and tissue degradation induced by IL-1α on bovine nasal cartilage (BNC) explants were investigated. Methods: Fresh BNC samples were prepared from a slaughterhouse under sterile conditions. BNC explants culture was treated with both IL-lα (10 ng/ml) and IL-4 (50 ng/ml) at the same time for 28 days. The morphological characteristics of explants were assessed by using histology techniques and invert microscopy. Matrix metalloproteinase-1 (MMP-1) production was assessed within different days by using Western blotting. Results: IL-lα induced prominent cartilage morphology degradation. The pro and active form of MMP-1 band substantially increased at day 21 of culture. In the presence of both IL-lα and IL-4, chondrocytes preserved their ordinary normal phenotype with intact extracellular matrix. In addition, a significant reduction in pro-MMP-1and inhibition of active MMP-1 was seen. Conclusion: In conclusion, IL-4 could be regarded as a potential candidate in cartilage protecting against the degradation changes of IL-lα. It seems that the preservation effect of IL-4 is associated with significant reduction of MMP-1. Key Words: Chondrocyte, Interleukin-1α, Interleukin-4, Matrix metalloproteinase-1, Bovine nasal cartilage  相似文献   
13.
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet.  相似文献   
14.
Drought is a lack of moisture in nature, consistent or unnatural. The term consistent refers to a state of shortage, and unnatural refers to the deviation from an index of the regional natural condition. The objective of this research was to examine and forecast the intensity, duration, frequency and extent of droughts in Fars province. For this purpose, and in order to survey droughts in the province, a standard precipitation index (SPI) was determined as a selective index, considering its capacity to facilitate accurate positional analysis between various regions of the drought extent. For this, precipitation data within the same statistical period of 32 years (1968 to 1999) in 5 time scales of 3, 6, 12, 24 and 48 months from some 26 stations located within and out of the province were used, and the trends were assessed by using a time series analysis. At the next stage, RUN theory and Markov Chain were combined, on this basis to create transition probability and a steady matrix, and then the conditions of long term droughts in the province in terms of number and duration were forecast for the subsequent 10 years. The characteristics of the extent of drought were determined by using the Geographic Information System (GIS) with the help of geo-statistical methods. The results of the drought station surveys for the mentioned characteristics showed that the highest drought intensity (in terms of % deviation from normal) was at the Gozoon station and the longest duration of drought in months was at the Polkhan station; droughts both of long duration and with the highest frequency during the statistical period were observed at the Jahrom and Darshahy stations. The map of the extent of droughts showed higher intensity in the south and central regions of the province, while northern parts of the province were less sensitive to the effects of droughts. Also, the results of the maps of drought duration in various periods showed that droughts in the south of the province were of higher intensity and longer duration than elsewhere.  相似文献   
15.
RAPDs and SSRs were used to study the genetic diversity of Iranian almond cultivars and their relationship to important foreign cultivars and three related species. Eight unidentified almond Shahrodi cultivars and three wild almonds (Prunus communis, Prunus orientalis and Prunus scoparia) were also included. Of the primers tested, 42 (out of 80) RAPD and 18 (out of 26) SSR primers were selected for their reproducibility and high polymorphism. A total of 664 polymorphic RAPD bands were detected out of 729 bands. The number of presumed alleles revealed by the SSR analysis ranged from 3 to 10 alleles per locus with a mean value of 6.64 alleles per locus. Both techniques discriminated the genotypes very effectively, but only RAPDs were able to discriminate the cultivars Monagha and Sefied. Results demonstrated an extensive genetic variability within the tested cultivars as well as the value of SSR markers developed in peach for characterization of almond and related species of Prunus. Dice similarity coefficient was calculated for all pair wise comparisons and was used to construct a UPGMA dendrogram. For both markers a high similarity in dendrogram topologies was obtained although some differences were observed. All dendrograms, including that obtained by the combined use of both the marker data, depicted the phenetic relationships among the cultivars and species, depending upon their geographic region and/or pedigree information. Almond cultivars clustered with accession of P. communis showing their close relationship. P. orientalis and P. scoparia were clustered out of the rest of P. dulcis.  相似文献   
16.

The aim of the present study was to determine the chemical composition of Sambucus ebulus and Actinidia deliciosa ethanolic extracts as well as their in vitro antifungal activity on the mycelial growth of the water mold, Saprolegnia parasitica. The preliminary minimum inhibition concentration (MIC) and minimum lethal concentration (MLC) were determined by the HeMP method and finally, concentrations of each extract ranging from 1 to 10% were prepared by an agar dilution method to assess the in vitro antifungal activity, quantitatively. Both herbal extracts inhibited growth of Saprolegnia hyphae in vitro. Complete in vitro growth inhibition was found at a concentration of ≥5% for S. ebulus, whereas it was not observed even at 10% concentration of A. deliciosa. Based on gas chromatography coupled with mass spectrometry (GC/MS) analysis, the main constituents of S. ebulus include monophthalate (66.17%), fatty acids (26.47%), phytol (4.25%), and acetic acid (2.11%). Using colorimetric assays, A. deliciosa contained phenolic contents at 162 mg gallic acid (GAE)/g DW and flavonoid contents at 2.31 mg quercetin (QE)/g DW. In conclusion, the results of this study indicated that S. ebulus and A. deliciosa showed some antifungal activities against S. parasitica with formerly exhibiting stronger activity (p < 0.05).

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17.

The aim of this study was to investigate the possibility of improving the growth and physiological indices of plant and fish by adding different levels of ascorbic acid (vitamin C) to water in the aquaponic system using Nile tilapia (Oreochromis niloticus) and saffron plant (Crocus sativus). 240# fish (12.5?±?0.21 gr) and 120# saffron corms (2.8?±?0.12 gr) were randomly assigned to 15 experimental units and underwent treatments of adding 0 (control), 2, 4, 6, and 8 mg L?1 ascorbic acid to water, every 6 days, for 8 weeks. The fish final weight and subsequently other growth performance indices increased in the treatment of 4 mg L?1 vitamin C compared to other treatments (P?≤?0.05). Some growth performances of saffron plants such as saffron production, in treatment of 6 mg L?1, were significantly higher than the control group and reached from 17.34?±?0.27 mg flower?1 in the control group to 25.4?±?1.61 mg flower?1 in treatment of 6 mg L?1. Measuring the serum biochemical parameters of the fish showed that, in the treatment of 8 mg/L ascorbic acid, the cortisol content in the blood reached its maximum (21.49?±?2.42 µg dL?1). The trypsin activity in proximal intestine and mid-intestine significantly increased in treatments of 2, 4, and 6 mg L?1, respectively. The current experiment showed that, by adding 4–6 mg/L ascorbic acid to the aquaponic system water (every 6 days), the optimal levels of Nile tilapia and saffron plant growth performances would occur.

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18.
Genetic Resources and Crop Evolution - Trifolium (Fabaceae) is widely distributed with more than 255 species. The current study contributed to the knowledge of the diversity and genetic population...  相似文献   
19.
The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is an important insect pest of canola, Brassica napus L., in Ardabil, Iran. Host plant resistance is an essential component of integrated management of P. xylostella. We investigated the preferences and performance of P. xylostella on nine commercial cultivars of canola, namely Zarfam, RGS003, Adder, Okapi, Opera, Hyola401, Ebonite Option500 and Elite under greenhouse conditions at 23 ± 1°C, 50 ± 5% RH and 14L:10D. In free-choice situation, oviposition was lowest on Opera (23.5) and highest on Zarfam (44.7). In the life table study, fecundity of new generation female moths was lowest on Opera (95.4) and highest on Adder (145.7). Survival from egg to adult was significantly lower on Opera, Option500 and Hyola401 than on other tested cultivars. The intrinsic rate of natural increase (r m) and population growth rate (λ) were lowest on Opera and highest on Zarfam. The generation time (T) was shortest on Zarfam (17.2 days) and longest on Hyola401 (19.9 days) whereas doubling time (DT) was longest on Opera (3.9 days) and shortest on Zarfam (3.0 days). Our results clearly suggest that Opera was the most resistant host among the tested cultivars and has the potential to be used in the integrated management of P. xylostella.  相似文献   
20.
It has been hypothesized that the uptake of organic as opposed to inorganic nitrogen compounds found in wastewater can be properly substituted for plant nutrients. The objective of this study was to compare effects of applying monosodium glutamate wastewater (MGW) and ammonium nitrate (NH4NO3) (AN) on nitrogen metabolism and growth of lettuce. The results showed that while NH4NO3 (AN), NO3-, nitrite content and NR activity increased the protein content of lettuce. Applying MGW with a high concentration of 17 amino acids and macro- and microelements improved the fresh weights of shoot and root as well as the protein content of lettuce. Antioxidant activities were not affected by AN and MGW, and their interaction effects only increased POD after 8 weeks. In conclusion, substituting a portion of the chemical fertilizers with MGW improved lettuce growth, but did not increase NO3- accumulation in leaves.  相似文献   
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