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1.
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   
2.
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±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   
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.
Organophosphorus (OP) compounds are cholinesterase-inhibiting chemicals used as pesticide. Exposures to OPs cause a significant number of poisonings and deaths each year. One of the reported adverse effects in human exposure to OPs is hyperglycemia. Animal studies have also shown altered glucose homeostasis following acute or chronic exposures to OPs. The objective of this paper is to provide a brief review of the mechanisms involved in the OP-induced glucose homeostasis alteration. To reach this objective, a search of the literature using Medline/Index Medicus, Scopus, and Chemical Abstract were performed, most of relevant citations were studied and summarized. To better understand the nature of glucose homeostasis, the principles of glucose production, metabolism, and its hormonal control have been discussed. Collection of theses studies support the conclusion that hyperglycemia is the outcome of acute or chronic exposure to OPs. OPs can influence body glucose homeostasis by several mechanisms including physiological stress, oxidative stress, inhibition of paraoxonase, nitrosative stress, pancreatitis, inhibition of cholinesterase, stimulation of adrenal gland, and disturbance in metabolism of liver tryptophan.  相似文献   
5.
  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   
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.
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   
9.
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   
10.
A few studies have illustrated the effects of sodium salt derived from alginic acid on different fish species. However, little is known about the effect of sodium alginate on catfish (Clarias gariepinus). Therefore, this study was performed to assess the use of low molecular weight sodium alginate ( LMWSA) in C. gariepinus. A total of 180 apparently healthy C. gariepinus with a mean body weight of 45 g were randomly divided into three equal groups (D1, D2 and D3). D1 the control group received a control diet, while D2 and D3 received 1% and 3% LMWSA, respectively, for 8 weeks. A challenge test against Aeromonas hydrophila was performed on 15 randomly selected catfish for 15 days. At the end of the experiment, catfish in D3 that received a diet of 3% LMWSA showed significant increases in the final body weight, weight gain and thermal‐unit growth coefficient compared with those in D2 and D1. There was a significant decrease in the erythrogram in D1 after the 4‐day pathogen challenge. A leucogram revealed leucocytosis, heterophilia and lymphocytosis in catfish in D2 and D3 compared with those in D1. After the 4‐day challenge, the following changes took place: lysozyme, nitric oxide, phagocytic activity and the respiratory burst were significantly elevated in catfish that received LMWSA and were more pronounced in D3 than in D1. The mortalities of catfish have been stopped after pathogen challenge from 8‐day in D1 and D2 where at 6‐day in D3. Thus, administration of 1% and 3% LMWSA enhances the growth, immune response and resistance of C. gariepinus against A. hydrophila.  相似文献   
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