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41.
AbstractIn order to reduce the damage caused by the late-season drought stress of canola, a factorial split-plot experiment was performed based on the randomized complete blocks design with three replications in Karaj, Iran. The treatments were Potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The simple effect of irrigation and potassium sulfate on all of the studied traits and the simple effect of cultivar on all traits except chlorophyll b were significant. The interaction effect of irrigation?×?cultivar on soluble carbohydrate, stomatal resistance, proline content, chlorophyll a and total chlorophyll content was significant. The interaction effect of irrigation?×?potassium sulfate on the amount of soluble carbohydrates, stomatal resistance and proline content of leaves was significant. In irrigation interruption from the pod formation stage, the promising line of L72, and in irrigation interruption from the flowering stage, the Neptune cultivar exhibited the most positive effect of potassium application on the studied traits. As a result, the application of potassium sulfate in addition to the L72 and Neptune cultivars is recommended in areas similar to the tested area encountering the late-season drought stress. 相似文献
42.
43.
Ghasem Mohammadi Taida Juliana Adorian Gholamreza Rafiee 《Aquaculture Nutrition》2020,26(5):1476-1492
The present research explored the effects of Bacillus subtilis on water quality, growth, immune responses, endotoxemia and protection against lipopolysaccharide (LPS) damages in Nile tilapia Oreochromis niloticus under biofloc system. B. subtilis was added at 0, 1, 2, 3 and 4 grams (1.19 × 108 CFU/g) per kg of basal diet, named T1 (control), T2, T3, T4 and T5, respectively, and fed to fish (14.82 ± 0.42 g) for 50 days. The concentrations of TAN, NO2 and NO3 were significantly reduced, and fish fed probiotics displayed significantly better growth performances versus the control, concomitantly with significantly enhanced activities of digestive enzymes. They also showed significantly declined serum glucose and cholesterol vice versa significantly improved immune responses (total protein, albumin, globulin, lysozyme, alternative complement, protease, immunoglobulins, alkaline phosphatase and respiratory burst), antioxidant capacity (superoxide dismutase, total antioxidant capacity, malondialdehyde) and skin mucus parameters (total protein, lysozyme, alternative complement, protease, immunoglobulins). Meanwhile, significantly lower endotoxin (LPS) concentrations were detected in the intestines and serum of fish fed probiotics. LPS challenge induced profound oxidative stress and impaired immune responses. Interestingly, probiotic alleviated LPS‐induced damages and restored mentioned parameters. In conclusion, B. subtilis effectively enhanced fish production, immunity and protection against LPS‐induced damages in tilapia under biofloc system. 相似文献
44.
Mojtaba Mohammadi Arani Amir Parviz Salati Omid Safari Saeed Keyvanshokooh 《Aquaculture Nutrition》2019,25(4):854-861
This study was carried out to assess the effects of Pediococcus acidilactici on zebrafish (Danio rerio). Different levels of P. acidilactici including 0, 1 × 106, 2 × 106, 4 × 106 and 8 × 106 colony‐forming unit per g of the diet (cfug?1) were examined in fish with 120 ± 10 mg weight for 60 days in a completely randomized design. The results showed that the best growth indices were recorded in group 4 × 106 cfug?1 (p < 0.05). The highest number of total viable count and lactic acid bacteria of intestine were found in group 4 × 106 cfug?1 (p < 0.05). The maximum activity of digestive enzymes including amylase, lipase, protease and alkaline phosphatase was observed in group 4 × 106 cfug?1. The highest activity for superoxide dismutase was recorded in group 4 × 106 cfug?1 while catalase, glutathione peroxidase and glutathione reductase showed the highest activity in group 8 × 106 cfug?1. The most growth inhibition zone of Aeromonas hydrophylla, Flavobacterium columnare, Vibrio anguillarum and Edwardsiella tarda was found in group 4 × 106 cfug‐1 (p < 0.05). Therefore, P. acidilactici as a probiotic improved growth and immunity of the zebrafish and could be used by zebrafish farmers. 相似文献
45.
Asad Mohammadi Zarejabad Mohammad Ali Jalali Mohammad Sudagar Somayeh Pouralimotlagh 《Fish physiology and biochemistry》2010,36(3):655-659
The effect of environmental salinity on hematological parameters of great sturgeon Huso huso juveniles was studied. Five-month-old juveniles (mean body weight 28.3 ± 2.1 g) were subjected to 0, 3, 6, 9, and 12 ppt
salinities. The hematological parameters were assessed after a period of 20 days rearing at these salinities. After transfer
from fresh water to brackish water, red blood cells, hematocrit, haemoglobin and mean corpuscular haemoglobin decreased, but
mean corpuscular volume increased. Mean corpuscular haemoglobin concentration, white blood cells, monocyte counts, and eosinophil
counts showed no significant variations with increase in environmental salinity. An increase was found in lymphocyte counts
according to the increase of salinity from 0 to 12 ppt, while the fresh water control group maintained basal levels. Decrease
in neutrophil counts was observed in great sturgeon with increase in environmental salinity. These data show significant effect
of salinity on the blood parameters of great sturgeon. 相似文献
46.
We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify seques- trated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m3.ha-1 for beech, 59 m3.ha-1 for hornbeam, 73 m3.ha-1 for oak, 41 m3.ha-1 for alder, and 32 m3.ha-1 for other species. The total optimum volume is 455.25 m3.ha-1. 相似文献
47.
Tropical Animal Health and Production - Separation of autosomal and sex-linked direct additive genetic effects has significant role in sheep breeding programs. Hence, this study was conducted to... 相似文献
48.
Reza Mohammadi Kouresh Nader Mahmoodi Reza Haghparast Stefania Grando Maryam Rahmanian Salvatore Ceccarelli 《Journal of Crop Science and Biotechnology》2011,14(4):281-288
This study was carried out to identify superior barley genotypes for the rainfed areas of western Iran using a participatory
varietal selection (PVS) approach. Three field experiments were conducted in two randomly selected farmers’ fields and in
one rainfed research station in the 2006–07 cropping season with 69 genotypes (including one local and one improved check).
Several univariate and multivariate methods were used to analyze qualitative (farmers’ scores) and quantitative (grain yield)
data. Individual farmers’ scores in each village were positively correlated, indicating that the farmers tended to discriminate
genotypes in similar fashion, although the genotypes actually selected by farmers were different in the two villages. In recent
years, a greater number of farmers in western Iran preferred the improved variety (Sararood-1) over the local barley (Mahali),
while in this project the farmers preferred the new genotypes over the two checks. This was also verified by the quantitative
data showing that the checks were outyielded by the new genotypes. Farmers were efficient in identifying the best genotypes
for their specific environment, as shown by biplot analysis, indicating their competence in selection. The genotypes selected
by the breeder and farmers were almost similar but some differences existed. In conclusion, PVS is a powerful way to involve
farmers for selecting and testing new cultivars that are adapted to their needs, systems and environments. 相似文献
49.
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
50.
Kambiz Baghalian Ali Haghiry Mohammad Reza Naghavi Abodollah Mohammadi 《Scientia Horticulturae》2008,116(4):437-441
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