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21.
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   
22.
新疆乌鲁木齐南山八一林场地衣生态地理学特征   总被引:1,自引:0,他引:1  
采用显色反应(CT)、微量结晶 (MCT)和薄层色谱 (TLC)等方法,分析乌鲁木齐南山八一林场地衣的物种组成及生态地理特征。结果表明:乌鲁木齐南山八一林场地衣资源较为丰富,共有7目、23科、51属、114种、9变型、9变种。含5种以上的大科共有7个,占总科数的30.43%,分别包括本地区50.98%的属和68.42%的种。地衣的地理成分可划分为12类, 包括欧亚-北美成分(39.47%) 、北半球广布成分(13.16%) 、中国特有成分(12.28%)和世界广布成分(10.53%)。该地区地衣种类与北美、欧洲等地在地衣区系上有一定的相似性,并具有明显的中国特有种类。  相似文献   
23.
24.
The aim of the present work was to investigate the effect of Rhus coriaria L. inclusion to the diet on some biochemical, haematological parameters and the level of antioxidant status of male rabbits. Adult rabbits were divided into five groups: one control (C) and four experimental groups. Experimental animals received sumac per os in feed in various doses (0.50%, 0.75%, 1.00% and 1.50%) for 90 days. Significant increase in PDWc (platelet distribution width) in E3 group when compared with control group was recorded. Sumac administration resulted in decreased cholesterol levels in all experimental groups vs. control group. Significantly lower level of cholesterol was found in E4 group with highest dose of sumac (1.50%). Higher values of total antioxidant status (TAS) and albumins were observed in all experimental groups in comparison with control group. A significant increase in TAS was detected in group E1 and E4. Concentrations of albumins were significantly higher in groups E3 and E4 vs. control group. Sumac administration had no significant effect on bilirubin content. In conclusion, these results show a positive effect of sumac consumption on antioxidant status and cholesterol level in adult male rabbits.  相似文献   
25.
Background: Spinal cord has a limited capacity to repair; therefore, medical interventions are necessary for treatment of injuries. Transplantation of Schwann cells has shown a great promising result for spinal cord injury (SCI). However, harvesting Schwann cell has been limited due to donor morbidity and limited expansion capacity. Furthermore, accessible sources such as bone marrow stem cells have drawn attentions to themselves. Therefore, this study was designed to evaluate the effect of bone marrow-derived Schwann cell on functional recovery in adult rats after injury. Methods: Mesenchymal stem cells were cultured from adult rats’ bone marrow and induced into Schwann cells in vitro. Differentiation was confirmed by immunocytochemistry and RT-PCR. Next, Schwann cells were seeded into collagen scaffolds and engrafted in 3 mm lateral hemisection defects. For 8 weeks, motor and sensory improvements were assessed by open field locomotor scale, narrow beam, and tail flick tests. Afterwards, lesioned spinal cord was evaluated by conventional histology and immunohistochemistry. Results: In vitro observations showed that differentiated cells had Schwann cell morphology and markers. In this study, we had four groups (n = 10 each): laminectomy, control, scaffold and scaffold + Schwann cells. Locomotor and sensory scores of cell grafted group were significantly better than control and scaffold groups. In histology, axonal regeneration and remyelination were better than control and scaffold groups. Conclusion: This study demonstrates that bone marrow-derived Schwann cells can be considered as a cell source for Schwann cells in SCI treatment. Key Words: Rats, Spinal cord injuries (SCI), Bone marrow, Schwann cells, Cell transdifferentiation  相似文献   
26.
Lycoriella auripila (Winnertz) (Diptera: Sciaridae) is one of the most frequently seen pests of cultivated mushrooms, Agaricus bisporus (Lange) Imbach. The effects of different concentrations of diazinon, imidacloprid and deltamethrin, and tobacco extract were tested against L. auripila on varieties 737 and A15 of button mushroom. Also, economic injury level (EIL) of fungus gnat was evaluated on variety 737. Different varieties of button mushroom were cultured and weight of harvested mushrooms was recorded to provide an estimate of yield loss. A linear regression analysis was used to determine the relationship between pest density and mushroom yield. Imidacloprid was the most effective insecticide against L. auripila on both varieties and caused 100 % control at the highest tested concentration. The lowest concentration of diazinon (500 ppm a.i.) increased pest emergence on 737 and A15. This is possibly due to the hormoligosis. Deltamethrin and tobacco extract were ineffective against fungus gnat between both varieties. High levels of adults of L. auripila were associated with significant reduction in mushroom yield. EIL were calculated according to the number of L. auripila required to cause the critical yield loss from the predictive model and by control costs, mushroom price, and the reduction of injury due to spraying by imidacloprid and diazinon. The lowest values of EIL were related to imidacloprid compared with diazinon. This is due to the different efficiency of these two insecticides, for it causes mortality in population of L. auripila. Based on this research, for the first time clear EILs are introduced to the button mushroom growers for treatment of L. auripila.  相似文献   
27.
We evaluated,for the first time in Turkey,the productivity of a feller buncher during clear-cut operations of two Brutian pine stands located in Canakkale,northwestern Turkey with different diameter classes and terrain conditions.In the first stand with 24.6 cm average DBH,the feller buncher cut full trees and moved them to roadside.In the second stand with 34.3 cm average DBH,the feller buncher cut trees in two stages due to their larger diameters and the relatively steep and rough terrain conditions of the site.The effects of specific stand features,DBH and tree height measurements were assessed through statistical analysis in relation to productivity.The results indicate that the average productivity for the first stand was about 118 m^3h^-1,while it was about 80 m3h-1 in the second stand.Even though tree diameter and volume were higher in the second stand,productivity decreased by32.3%due to extra time spent on the two-stage cutting operation.The results revealed that harvesting operations should be planned carefully and the right equipment selected by accounting for different tree sizes,terrain conditions and machine specifications in order to better understand their effects on production.  相似文献   
28.
A rhizobox experiment was conducted to compare the differences of soil potassium (K) distribution and absorption between two cotton (Gossypium hirsutum L.) genotypes under drought and K‐deficit conditions. Treatments included two levels of water (drought and optimum soil moisture: 25% and 35% volumetric water content) and K fertilizer rates (0 and 0.48 g potash kg?1 soil) applied to two cotton genotypes (namely HEG and LEG). Both the genotypes showed significant differences in total K accumulation without exogenous K addition. After absorption, soil content of the readily available potassium (RAK) decreased rapidly. This promoted the conversion of the mineral K into slowly available potassium (SAK). Drought significantly decreased the cotton growth and K use efficiency, and thereby reduced the effect of K fertilizer. Consequantly, the contents of RAK and SAK were greatly increased. However, K bioavailability was decreased under water stress conditions. Differences in root parameters and soil microorganisms between two cotton genotypes were significantly increased and had marked relations with available soil K contents. This study provides important information for understanding the mechanism of K use efficiency, especially under water and K stress.  相似文献   
29.
A karyotype study was performed on 15 populations of Eremostachys laciniata Bunge from Iran in order to quantify the extent of cytological variation for use in breeding programmes. Ten mitotic root tip cells at the metaphase stage were prepared from each population by the squash method. The chromosomes of suitable mitotic cells were counted and various parameters, including long and short arm lengths, chromosome lengths, total length of the haploid chromosome complement, arm ratios, and the centromeric index, were measured. All 15 populations were diploid with 2n = 2x = 22 and were differentiated by their karyotypic parameters. All 15 E. laciniata populations occupied Class 1A of Stebbins’ karyotype classification, indicating the presence of a primitive symmetrical karyotype. The size of the mitotic chromosomes was medium, and mean chromosome lengths ranged from 3.84 to 4.77 μm. The shortest chromosome lengths were observed in the Ajabshir population and the longest in the Heydarabad population. The Heydarabad population also had the longest total chromosome length and the Ajabshir population had the shortest total chromosome length. The centromeric indices of the chromosome complements varied from 39.3% to 43.7%. Metacentric chromosomes were the most common in all populations, whereas submetacentric chromosomes were rare. The A1 index varied from 0.215 (Areshtanab) to 0.337 (Til). The A2 index ranged from 0.116 (Til) to 0.143 (Kaleybar), and the karyotype asymmetry index varied between 0.051 and 0.097. The results of a principal component analysis (PCA) showed that the main elements of the first three main principal components accounted for 97% of the total variance. Cluster analysis by Ward’s method indicated that all 15 populations could be classified into three clusters. Finally, the results of the karyotypic parameters showed that the Til, Heydarabad, and Marand populations had higher levels of karyotypic heterogeneity and may be useful when developing breeding programmes.  相似文献   
30.
The use of morphine has been demonstrated to increase susceptibility to infections. Herpes simplex virus type 1 (HSV-1) is a highly successful pathogen among immunocompromised individuals. In the present study, due to the importance of HSV vaccination in morphine abusers, the effects of chronic morphine exposure on the host response to a HSV-1 gB DNA-based vaccine have been investigated. The study is addressing an important aspect of vaccine development among the susceptible (immunocompromised) hosts. BALB/c mice were exposed to morphine over 11 days. They were then vaccinated with DNA vaccine or KOS strain as a live vaccine. The findings showed that the morphine-treated animals failed to respond to DNA vaccination evaluated by the anti-HSV gB antibody titer, delayed type hypersensitivity (DTH) and lethal HSV-1 challenge. Under the same conditions, the KOS vaccine showed a reduced Ab titer and DTH response in morphine-treated mice, but could protect mice against the lethal challenge and was safe for vaccination of morphine-treated animals.  相似文献   
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