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101.
Genetic Resources and Crop Evolution - Citrus plants are one of the most important fruit plants which are consumed all over the world. The breeding of these valuable fruit plants is based on... 相似文献
102.
Sareh Baghaee-Ravari Heshmat Rahimian Masoud Shams-Bakhsh Emilia Lopez-Solanilla María Antúnez-Lamas Pablo Rodríguez-Palenzuela 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(3):413-425
Characteristics of forty strains from macerated potato tubers and water-soaked lesions of some ornamental plants were studied
in north parts of Iran. The causal organisms isolated from infected tissues were identified as Pectobacterium spp. based on their physiological and biochemical assays and confirmed by species and subspecies specific PCR and RFLP analysis
of 16S–23S intergenic transcribed spacer region. Artificial inoculation of isolates to their related hosts generated the same
symptoms on potato and ornamental plants, from which the same bacteria were isolated and identified. We detected two groups
of atypical isolates in this study. The first group from potato classified as Pectobacterium carotovorum subsp. carotovorum by phenotypic tests but was unable to elicit HR on tobacco leaves, to grow at 37°C and to amplify the pel gene relevant to this subspecies. The second one from ornamental plants which was again characterized as Pectobacterium carotovorum subsp. carotovorum in biochemical assays, produced a unique ITS-RFLP profile different from all of known Pectobacterium species and subspecies. Our findings based on phylogenetic analysis using concatenated partial sequences of housekeeping
genes mdh and gapA, indicated the occurrence of P. wasabiae as a novel species in potato storage in Iran. Furthermore we detected a distinct clade of Pectobacterium spp. from some ornamental plants including Schlumbergera bridgesii, Syngonium podophyllum and Iris spp. 相似文献
103.
H. Rezaei N. A. Khosh Kholgh Sima M. J. Malakouti M. Pessarakli 《Journal of plant nutrition》2013,36(11):1903-1917
ABSTRACT This study was conducted in a greenhouse to evaluate the root and shoot response of canola (Brassica napus L.) to salt-stress conditions and the remobilization, deposition, and input rate of sodium (Na), potassium (K), and magnesium (Mg) at different salinity levels using two canola cultivars. A salt-tolerant (‘Kristina’) cultivar and a salt-sensitive (‘Hyola 308’) cultivar were grown in nutrient solutions with 0, 50, 100, 150, and 200 mol m?3 NaCl for 7 d. The plants were harvested after 6, 12, 18, and 24 h and 3 and 7 d after salt treatment. The results indicated that increasing salinity significantly decreased shoot and root weights 7 d after treatment. Also, K content and K-Na selectivity decreased in both cultivars, but the changes in ‘Hyola 308’ were greater than in ‘Kristina.’ Electrolyte leakage was increased significantly by salinity, and cell-membrane stability of ‘Hyola 308’ was damaged more than that of ‘Kristina’. Sodium import, transport, and deposition was increased by salinity concentration but remobilization was decreased. The K and Mg import, deposition, and remobilization were also decreased. From this experiment we can conclude that greater K and Mg remobilization in ‘Kristina’ could be a mechanism of salt tolerance in canola. 相似文献
104.
F. Kamyab-Talesh S. F. Mousavi R. Asadi M. Rezaei 《Archives of Agronomy and Soil Science》2013,59(9):1303-1314
Parts of paddy fields in Mazandaran Province, northern Iran, are confronted with soil and water salinity. To screen proper rice cultivars, an experiment was performed with eight modified rice cultivars under four levels of irrigation water salinity (1, 2, 4 and 6 dS m?1) with three replications, in Amol, northern Iran. The objective of the present study was the evaluation of eight screening indices for identifying salinity tolerance of these cultivars, so that suitable cultivars can be recommended for the cultivation with saline irrigation water in paddy fields. To evaluate the resistance of these cultivars to salinity stress, different indices were calculated. The results showed that Khazar cultivar was the most salt-sensitive cultivar in all salinity levels. In the irrigation salinity levels of 2 and 4 dS m?1 Neda cultivar and in the level of 6 dS m?1 Dasht cultivar were the most salt-resistant cultivars. In the two irrigation salinity levels of 4 and 6 dS m?1, the mean productivity index was the most effective in the screening of salt-resistant cultivars. Harmonic mean, geometric mean productivity, stress tolerance index and mean productivity indices were found to be the best indices in screening resistant cultivars. 相似文献
105.
106.
This study was conducted to determine effects of intravenous detomidine on intraocular pressure (IOP) readings obtained by applanation tonometry in clinically normal horses. Twenty horses were randomly divided into two groups of 10 each (treatment and control). All horses in the treatment group received intravenous detomidine alone (20 μg/kg). The horses in the control group received only intravenous saline (0.2 mL/100 kg). The IOP values were measured before the treatment (T0) and then at 5 (T5), 20 (T20), 60 (T60), and 120 (T120) minutes after drug administration in both groups. A significant decrease in IOP values was observed in both right and left eyes of the horses in the treatment group at T5, T20, and T60 in comparison with the baseline values (P < .001). The observed decrease was only statistically significant in the right eyes of the treatment group horses at T120 (P = .044). Mean IOP was not significantly altered at any time point during the treatment period compared with the baseline evaluations in both eyes of the horses in the control group. This study demonstrates that the use of intravenous detomidine lowers IOP quickly. 相似文献
107.
Ehsan Eyshi Rezaei Mohammad Kafi Mohammad Bannayan 《Journal of Crop Science and Biotechnology》2013,16(3):237-244
Persian shallot (Allium altissimum Regel.) was grown under fully irrigated conditions in a 2-year-field experiment (2010–2012) in the northeast of Iran to study and determine (i) radiation and nitrogen-use efficiency, (ii) growth analysis, (iii) carbon partitioning, and (iv) biomass production under different rates of nitrogen and cultivated bulb weights. The field experiment was performed as a randomized complete block design with a factorial arrangement of four nitrogen levels (control (100), 200, 250, and 300 kg ha?1) and two levels of cultivated bulb weight (10–20 and 20–30 g) with three replications in both years of the experiment. Our results showed that increasing the nitrogen rate and bulb weight significantly enhanced Persian shallot production. Radiation-use efficiency (1.06 to 1.27 g MJ?1), maximum crop growth rate (8.3 to 11.2 g m?2 d?1), and maximum leaf area index (1.3 to 2.6) showed a positive correlation with nitrogen rate and bulb weight. Nevertheless, nitrogen-use efficiency (0.87 to 2.38 g bulb per g nitrogen) indicated a negative relationship with applied nitrogen rate. Moreover, increasing the nitrogen application rate increased the carbon allocation to above-ground organs. On the other hand, nitrogen limited conditions increased the carbon allocation to underground organs and carbon remobilization from stem and leaves to bulbs during the late growth season. Increasing the nitrogen application rate and bulb weight may be appropriate practices for enhancing Persian shallot production; however, evaluation of the impact of nitrogen on the quality of bulbs needs to be investigated. 相似文献
108.
Mehri Javdi Ali Haghnazari Masoud Tohidfar Shahin Negari Behzad Ghareyazi 《Euphytica》2010,173(2):185-191
Successful identification of homozygous and heterozygous transgenic plant with currently available techniques such as southern
blot hybridization, dot blot hybridization, fluorescence in situ hybridization (FISH) and so on, demands tedious and time-consuming
procedures with a high proportion of ambiguous results. Real-time PCR is a quantitative and extremely precise method with
high throughput that could be applied to the analysis of large number of plants differing only by a factor of two in the amount
of target sequences. In the present study, we determined zygosity level of transgenes in cotton [Gossypium hirsutum L.] with two zygosity assays, based on TaqMan technology that uses a fluorogenic probe which hybridizes to a PCR target sequence flanked by primers. TPS, a single copy
gene per haploid Gossypium hirsutum genome was used as the endogenous reference to estimate copy number of transgene. Both assays were accurate and reproducible
in determination of the number of transgenes present in a cell line. These methods are standard curves and Delta delta C
t method. 相似文献
109.
Species of barberry (Berberis vulgaris L. var. asperma) is cultivated in arid and semi arid areas of Iran (South Khorasan province). It is widely used as a food additive. Fruits of this species are seedless, while wild type barberries produce seeds in the same area. In this study, we investigated the mechanism of seedlessness in seedless barberry by pollen viability test, field pollination experiments and microscopic observation of pollen tube growth in pistil and ovule development. For comparison, we also examined ovule development in wild type barberry (B. crataegina DC). In seedless barberry pollen germination was about 54%. Seedless barberry produced 20% seeded fruits when pollinated with pollen of wild type barberry. There was a sharp decrease in fruit set in emasculated unpollinated flowers of seedless barberry. In seedless barberry, a large number of pollen grains (about 370) were observed on stigma of each flower at 12 h after balloon stage (ABS). Most of them germinated and penetrated intracellular area of stigma surface, but no pollen tube reached ovary. In seedless barberry, many ovules did not have any embryo sac or had a very small incomplete embryo sac. In addition, unfused polar nuclei were clearly recognized in some cases at 14 days after full bloom (AFB). However, in wild type, double fertilization was accompanied by disappearance of polar nuclei. In seeded barberry, the cellularized endosperm became apparent at seven days AFB. At 21 days AFB, all ovules of seedless barberry were degenerated, while at the same time in wild type, one or two ovules of each flower were normal and were developing into complete seeds. Results showed that self-incompatibility has a main role in seedlessness of seedless barberry. However, the high frequency of abnormal ovules and single fertilization can be considered as two other reasons of seedlessness. Due to our results, fruits of seedless barberry were set by stimulative parthenocarpy. 相似文献
110.
Effect of different levels of dried citrus pulp on performance,egg quality,and blood parameters of laying hens in early phase of production 总被引:1,自引:0,他引:1
Nazok Ahmad Rezaei Mansour Sayyahzadeh Hadi 《Tropical animal health and production》2010,42(4):737-742
Utilization of agricultural wastes in animal nutrition is a matter of great concern. Dried citrus pulp (DCP) is a potential
source of some valuable nutrients for animal and poultry. In an experiment with completely randomized design, the effect of
different levels (0%, 4%, 8%, 12%, and 16%) of DCP was evaluated on performance, egg quality, and blood parameters of laying
hens from 25 to 37 weeks of age. The birds were randomly allocated to five groups with six replicates and three birds in each
replicate. The results showed that with increasing the level of DCP up to 12%, there were no significant differences among
treatments for feed intake, egg production, egg mass, feed conversion ratio, final body weight, yolk index, and yolk color.
There were no significant differences between treatments in shell thickness, eggshell index, egg score, and Haugh unit. Utilization
of DCP up to 16% significantly increased serum glucose and high-density lipoprotein and reduced cholesterol, low-density lipoprotein,
and triglycerides (P < 0.05). Results of the present study indicated that use of 12% DCP in laying hen diets had no adverse effect on performance
and egg quality of laying hens in early phase of production. 相似文献