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31.
32.
ABSTRACT

The interaction between soil salinity and infection caused by Verticillium dahliae was studied in pistachio (Pistacia vera) in a greenhouse experiment. Treatments consisted of 0, 1400, 2800, and 4200 mg sodium chloride (NaCl) kg? 1 soil and three rootstocks (Sarakhs, Badami, and Qazvini cultivars). They were gradually exposed to salinity stress before and/or after root inoculation with a water suspension of 107 conidia/mL of a pistachio isolate of V. dahliae. Salt stress significantly increased rootstock shoot and root colonization by V. dahliae. All rootstocks were susceptible to V. dahliae, but symptoms of the disease appeared earlier in Sarakhs, a salt sensitive cultivar. Moreover, salinity and V. dahliae interaction increased the concentrations of sodium (Na), potassium (K) and chloride (Cl), but decreased the K/Na ratio in all rootstocks. Shoot and root tissues of inoculated Sarakhs and Qazvini (a salt tolerant) contained the highest and the lowest concentrations of Na, K,and Cl, respectively. In salinity treatments, shoot and root dry weight of all rootstocks decreased as compared with controls. Sarakhs showed smaller shoot and root dry weight than Qazvini and Badami. Also, increasing the NaCl level increased accumulation of Na, K, and Cl in shoot and root of the rootstocks. Sarakhs showed higher concentrations of ions in the shoot and root. Based on shoot and root dry weights and ion accumulation, Sarakhs and Qazvini were susceptible and tolerant to salinity, respectively.  相似文献   
33.
This study investigated areas for potential application of information and communication technologies (ICTs) in the agricultural extension system of Iran. Two hundred forty-one extension staff (out of 1,145) in the Ministry of Agriculture were selected and studied as a sample through a stratified random sampling technique. The findings revealed that six factors/components containing 32 variables determined about 68.91% of the variations in the areas of application. The six factors were Management of documentation and preparation of extension information (14.88% of variance), Planning and implementation of extension education programs (13.6%), Professional empowerment of extension agents (10.8%), Expansion of intra-organizational relationships (10.27%), Facilitation of organizational processes (9.7%), and Improving communication through e-mail services (9.64%).  相似文献   
34.
The aim of this study was to investigate the expression of membranous epidermal growth factor receptor in colorectal adenocarcinoma and it's correlation with clinicopathological features. Fifty formalin-fixed, paraffin embedded archival specimens of colorectal cancer were included randomly as cases. Immunohistochemical staining was performed to assess EGFR expression. The results were correlated with the clinicopathological features of colorectal tumor tissues. More than 1% of membranous EGFR expression was found in 24 (48%) of cancer specimens. The immunoreactions intensity was classified as weak, moderate and strong representing 2, 22 and 24%, respectively. According to multivariate analysis, EGFR expression was not significantly associated with age, sex, tumor site, stage, grade and type of tumor in cases. These results suggest that the assessment of EGFR expression in colorectal cancer by conventional immunohistochemistry has not proven its predictive value and can not be useful to predict about outcome of patients.  相似文献   
35.
Seed priming and drying condition effects were investigated immediately after seed-priming and 9 week after the storage. In this experiment, carrot seeds of 'Forto C.V.' were used. These seeds were individually primed for 10 days at 20 degrees C and in PEG (6000) (273 g L(-1)) and KNO3 (200 mmol) solutions. Then they were dried for 1 and 2 h at 15, 25 and 30 degrees C, respectively. One part of the seeds was stored at 5 degrees C in RH/45% For 9 week. Chemical priming effects, drying temperature as well as germination temperature on different traits especially germination percentage were significant. However, drying time had no significant effect on germination percentage after storage period. PEG priming and drying at 25 degrees C for 2 h provided the best condition for germination percentage. Using the best material for pre-priming, along with suitable drying management with appropriate quality and good conditions of the storage is important.  相似文献   
36.
The aim of this study was to evaluate the prevalence of chronic gastritis in pet dogs, to determine the histopathologic changes of gastric mucosa and, to determine its relationship with canine gastric Helicobacter infection. Sixty percent (n = 18), 27% (n = 8) and 13% (n = 4) of the examined stomachs showed normal, congested and erosive gastric mucosa respectively. Histopathologic examination was confirmed the presence of chronic gastritis in 40% of dogs (n = 12). Lymphocytic-plasmacytic gastritis was the most common type of chronic gastritis. Gastric Helicobacter was detected in cytological examination of 26 out of 30 dogs (86.6%) but in the PCR analysis, 93% of gastric samples were positive for GHLO. There was no significant relation between the presence of Helicobacters and chronic gastritis (p>0.05). Follicular gastritis was detected in 12 cases (40%) and there was also no significant correlation between its presence and GHLO's infection (p>0.05). In conclusion, chronic gastritis can be considered as a prevalent disease especially in dogs. Nutritional and environmental factors as well as individual immune response may have role in induction of chronic gastritis, but the clinical significance of these histopathologic changes should be evaluated.  相似文献   
37.
ABSTRACT

1. Theoretically, haplotype blocks might be a more suitable alternative to SNP genotypes as they are usually better at capturing multi-allelic QTL effects, compared to individual SNP genotypes in genome-wide association studies. The objectives of this study were to identify genomic regions related to egg weight traits by Bayesian methods (BayesA, BayesB, and BayesN) that fit fixed-length haplotypes using GenSel software.

2. Genotypes at 294,705 SNPs, that were common on a 600K Affymetrix chip, were phased for an egg-laying hen population of 1,063 birds. Recorded traits included first egg weight (FEW) and average egg weight at 28, 36, 56, 66, 72 and 80 weeks of age.

2. Fitting 1Mb haplotypes from BayesB resulted in the highest proportion of genetic variance explained for the egg weight traits. Based on the trait, the genetic variance explained by each marker ranged from 27% to 76%.

3. Different haplotype windows associated with egg weight traits only explained a small percentage of the genetic variance.

4. The top one 1-Mb window on GGA1 explained approximately 4.05% of total genetic variance for the FEW. Candidate genes, including PRKAR2B, HMGA2, LEMD3, GRIP1, EHBP1, MAP3K7, and MYH were identified for egg weight traits.

5. Several genomic regions, potentially associated with egg weight traits, were identified, some of which overlapped with known genes and previously reported QTL regions for egg production traits.  相似文献   
38.
In arid and semi-arid regions, where water availability is a major limitation in crop production, using alternative water resources, such as saline water is one way to utilize lands. Chamomile (Matricaria recutita L.) as an annual medicinal herb may be considered as an economic substitute for field crops irrigated with fresh water since it has adaptability to wide range of climate and soil. A field examination was conducted during 2004–2005 using complete randomized block design with four replications in order to evaluate the effects of saline irrigation water on morphological characters, mineral content, oil quantity (content, yield), oil composition and apigenin content of chamomile. In each plot, 0.6 g/m2 of seeds were grown in 4 rows. The irrigation water had five different salinity levels (0, 4, 8, 12 and 16 dS m−1). The investigated characters through cultivation were fresh weight of flower (g), dry weight of flower (g), dry weight of aerial stems (g), dry weight of root (g), oil yield (kg/h), oil content (%), oil quality and apigenin content (%). After harvesting, the content of minerals (Na+, Cl, K+, Ca2+, Mg2+) were evaluated in aerial parts and roots of each plot. Mean comparisons for fresh flower weight in different treatments showed that fresh flower yield decreased with increasing salinity and it was higher in control compared to others. Analysis of variance showed that saline irrigation water had no significant effect on oil quantity (yield and content), oil quality (chemical composition) or apigenin content. Our results showed that chamomile is able to maintain all its medical properties, under saline condition and could be cultivated economically in such conditions.  相似文献   
39.
40.
Genetic parameters for birth weight (BW), weaning weight (WW) and pre-weaning daily gain (PWDG) in Iranian Mehraban sheep were estimated using restricted maximum likelihood (REML) procedure. Six different animal models were fitted, differentiated by including or excluding maternal effects, with and without covariance between maternal and direct genetic effects. The estimates for direct heritability ranged from 0.26 to 0.53, 0.18 to 0.32 and 0.15 to 0.33 for BW, WW and PWDG respectively. The estimates were substantially higher when maternal effects, either genetic or environmental, were ignored in the model. The results of this study show that full models with maternal genetic and environmental effects gave the most accurate estimates for early growth traits.  相似文献   
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