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1.
Nuclear magnetic resonance ‐based metabolomics was applied to study effects of egg aging on ovarian fluid metabolites in rainbow trout, Oncorhynchus mykiss. The eggs of three females were pooled and then assigned to three plastic vials for 18 days in vitro storage at 4°C. Ovarian fluid samples were taken 0, 6, 12 and 18 days after storage. Three groups of metabolites including amino acids, osmolytes and energy metabolites were found to change during storage period. The glucose levels of ovarian fluid showed significant decreases on days 12 and 18 after storage (< .05). For acetoacetate and acetate, significant increases were observed, respectively, on days 12 and 18 after storage (< .05). The creatine levels of ovarian fluid increased significantly on days 12 and 18 after storage (< .05). Lactate levels in ovarian fluid elevated during storage period (< .05). Glycerol levels showed a significant increase on days 12 and 18 after storage (< .05). The values of osmolytes in ovarian fluid (e.g., betaine, taurine, trimethylamine‐N‐oxide, N,N‐dimethylglycine) showed a decreasing trend on day 12 which continued until the end of storage on day 18 (< .05). Almost all amino acids elevated on days 12 and 18 after storage (< .05). After an apparent elevation in isoleucine levels on days 6 and 12, this amino acid decreased on day 18 after storage (< .05). The osmolytes might act as antioxidant against free‐radicals produced as a result of over‐ripening. Glucose can be used as energy resource for eggs and bacteria during ova storage. Also, change pattern of amino acids indicate hydrolysis of proteins as the time of storage increases.  相似文献   
2.
  1. The objective was to investigate inbreeding depression for some economic traits of Mazandaran native fowls using data collected from 1992 to 2012 (21 generations) using a REML animal model of significant fixed and random effects with inbreeding of birds and dams as covariates.

  2. The mean inbreeding coefficient (F) for the whole population and dams was 4.67% and 4.12%, respectively, and most of the inbred birds (75.79%) and inbred dams (72.58%) had F < 12.5%.

  3. Individual and dam inbreeding trends were 0.55% and 0.53% per year.

  4. Inbreeding depression for body weight at hatch, at 8 weeks and 12 weeks of age, age at sexual maturity, weight at sexual maturity, egg weight at 1st d of laying and average egg weight at 28, 30 and 32 weeks of laying due to a 1% increase in individual inbreeding were ?0.11 g, ?3.1 g, ?1.3 g, 0.15 d, 0.59 g, ?0.05 g and ?0.03 g, respectively.

  5. A 1% increase in maternal inbreeding resulted in a reduction of 0.06, 0.6 and 3.6 g in body weight at hatch, 8 weeks and 12 weeks of age.

  相似文献   
3.
One of the most important elements affecting the growth and development of a plant is salinity. Therefore, to evaluate the effect of salinity on some physiological aspect of Strawberry (Fragaria x ananassa Duch.) plants cv. Camarosa, a greenhouse experiment was conducted at Vali-e-Asr University of Rafsanjan in 2009. This study was carried out as Factorial experiment based on RCD design with 4 replications to determine the influence of salinities (0, 30, 60 and 9 mMol.L-1) on proline, soluble sugars content, chlorophyll a (CHLa), chlorophyll b (CHLb), total chlorophyll (TC), Spad and chlorophyll florescence. Results indicated that fresh leaves tissue were used to measure proline, soluble protein and soluble sugars content, CHLa, CHLb, TC. Salinity treatment significantly increased proline content, soluble sugars while chlorophyll a (CHLa), chlorophyll b (CHLb), Spad and chlorophyll florescence significantly decreased. Nine day after NaCl exposure, Fv/Fm and Spad in 60 and 90 mM NaCl were significantly lower than control. It was concluded that this cultivar of strawberry may uses osmoregulation by increasing proline and soluble sugars level in order to tolerate salinity conditions.  相似文献   
4.
The aim of this article is to investigate and measure farmers' satisfaction regarding extension services to better understand why farmers do or do not participate in such programs in Iran. Our study sample consisted of 240 farmers selected through simple quota random sampling (160 male and 80 female) from a list of names from the extension organization. Data were gathered through a face-to-face survey of farmers. Structural equation modeling analysis revealed that perceived quality and perceived value significantly predicted farmers' overall satisfaction. Furthermore, farmer satisfaction can predict farmers' loyalty to extension program activities. From a practical point of view, the present study provides a justification for using perceived quality and perceived value in policy and decision making that seeks to encourage farmers to use agricultural extension programs (AEPs).  相似文献   
5.
A review of publications on “Strawberry” was done by using the Scopus database for the period 1960–2016. A total of 10,400 articles were found in the database and analyzed using a variety of measures. Results show that publication increased exponentially from 1960 to 2016. Multiple authors are collaborating in strawberry research. Acta Horticulturae was the most productive journal. The United States of America was the most productive country. The greatest portion of the research was concerned with medicinal benefits of strawberries to humans. This work will be useful to researchers in identifying trends in strawberry research.  相似文献   
6.
Genetic Resources and Crop Evolution - The genus Epilobium of Family Onagraceae is taxonomically a difficult group due to frequent inter-specific hybridization and species morphological overlaps....  相似文献   
7.
8.
Macro- and Microsymptoms of Zinc Deficiency in Higher Plants The development of zinc deficiency symptoms was studied in eight different plant species grown under controlled experimental conditions in soilless sulture. The following results were obtained. One symptom of zinc deficiency was found to be the development of a violet to red colouring matter which first appeared in the form of small dots or as spots of discolouration which later covered the entire leaf. This discolouration was found primarily in young but already completely developed leaves. Here, the symptoms started to devlop in single cells. Further symptoms of zinc deficiency were observed to be a retarded growth, short internodes, small leaves and a very poor formation of roots.  相似文献   
9.
The growth and Zn-, Fe- and P-contents of higher plants in relation to Zn-supply The influence of varied supply of zinc was studied on nine different plant species growing in water culture under controlled experimental conditions. The results of the trials were as follows: 1. The vegetative development of the plant was enhanced by increasing supply of zinc in the nutrient solution. Visible symptoms of zinc deficiency were observed in all plants tested up to a level of 10 μg Zn/l in the nutrient medium. Latent zinc deficiency is to be expected when the zinc supply lies between 10 and 100 μg/l. Normal plant development was recorded in the 100 μg/l Zn/l treatment. 2. The zinc content of all plant organs (except in the trial series without zinc) rose with increasing zinc supply. Zinc contents differed greatly depending on plant species. In onions deficiency symptoms appeared during plant development at a zinc content below 7.8 ppm in the dry matter of the leaves. The corresponding value for flax was 21.5 ppm Zn. The range of latent zinc deficiency was characterized by zinc contents between 13.8 and 37.5 PPm. The optimal zinc content differs depending on plant species. For these very varied Zn-treatments and different species, values between 15.8 and 52.0 were found. 3. Leaf Zn content does not always provide a reliable measure of the Zn-nutritional status of the plant. This is, because zinc contents are extremely dependent upon plant species, the age of the plant, and experimental conditions, etc. 4. A higher zinc concentration was measured in older than in younger leaves. 5. The phosphorus contents in all organs were depressed by increasing zinc supply in the nutrient solution. The leaves of the plants in the trial series without zinc had the heighest phosphorus content. The P:Zn ratio at optimal plant growth differs between species. In the control plants this ratio, measured in the younger leaves, was 100 in millet and 262 in soybean. When the symptoms of zinc deficiency are very pronounced, these values lie above 1000. Zinc deficiency does not occur if the P:Zn ratio is below 250 (except in Cotton and beans). 6. Increasing zinc supply led to a decrease in the iron content in the plant organs of all species tested. The iron content was particularly high in those plants which did not receive any zinc.  相似文献   
10.
对生长在伊朗北部丘陵地带的8株欧洲鹅耳的根面积比率和根系拉伸强度进行了测定,评估了欧洲鹅耳根系生物力学特性。应用剖面挖掘法测得土层深度为0.1米的样品根面积比率。共用了123份根样品分析根系拉伸强度。结果表明,根面积比率随土层深度增加而减小,变化规律遵从幂函数;上坡面和下坡面根面积比率无统计差别。根系可达到的最大土层深度为0.75米,但是最大根面积比率存在于土层深度0.1米内。下坡面最小和最大根面积比率分别为0.004%和6.431%;而上坡面的根面积比率分别为0.004%和3.995%。上、下坡面根数无显著差异,而且90%以上的根系深入到50-60厘米的土层中。Spearman双变量相关性分析结果表明,根面积比率与根数无显著关系。平均根拉伸强度为31.51&#177;1.05MPa,且根系直径越粗根拉伸强度越小,遵从幂函数变化。图5表1参38。  相似文献   
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