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排序方式: 共有231条查询结果,搜索用时 78 毫秒
21.
Ali Akbar Ghotbi-Ravandi Maryam Shahbazi Mohammad Pessarakli 《Journal of plant nutrition》2016,39(8):1174-1185
To study the effects of progressive drought stress on photosystem II behavior of wild type (Spantaneum) and cultivated barley (Morocco), different levels of soil water availability, including control, moderate, mild, and severe water stress (70%, 50%, 30%, and 10% water holding capacity of soil, respectively) and rehydration were used. Polyphasic OJIP fluorescence transient of Morocco plants exhibited a considerable increase in fluorescence intensity at O, J, and I steps under mild and severe stress relative to slight increase in wild barley. Values of fluorescence parameters and quantum efficiencies, including minimal fluorescence, relative variable fluorescence at phase J and I, maximal quantum yield of photosystem II (PSII), performance index, electron transport yield, and excitation transfer efficiency were influenced by water stress in both genotypes. These parameters were significantly less affected in wild type barley by progressive drought stress compared to Morocco. After re-watering, both genotypes were able to restore from severe drought in most of the traits. Based on our findings, highly correlated values of relative water content (RWC) and independent JIP-test parameters (P < 0.01) indicate that the chlorophyll a fluorescence induction technique is sensitive to plant water status and performance index represent an accurate and reliable indicator for early stress detection and also explore plant vitality under water stress. 相似文献
22.
Maryam Haghighi Mohsen Kafi Atena Sheibanirad Mohammad Reza Sharifinia 《Journal of plant nutrition》2016,39(10):1460-1471
Ornamental kale (Brassica oleracea var. Acephala) is usually planted from early autumn until late winter. Since most of the plants used for phytoremediation cannot be grown during this time, kale can be a suitable option for phytoremediation and utilized during autumn and winter in urban landscape, especially in metropolitan areas where high levels of cadmium (Cd) and lead (Pb) pollutions exist. Kale growth in saline soil at different growth stages (germination and vegetative growth stages) was studied in this investigation. A factorial experiment based on completely randomized design (CRD) with four replications was used in this study. Treatments included three levels of sodium chloride (NaCl) (0, 30, and 60 mg/kg), four levels of Cd (0, 4, 8, and 16 mg/kg), and four levels of Pb (0, 1, 5, and 10 mg/kg). Results indicated that increase in Cd and Pb concentrations in the soil decreased fresh and dry weights of the plants. The results of the various growth stages revealed that under salinity stress, kale plants were able to absorb more Pb than Cd and effectively remediate Pb in polluted and saline lands. Cd accumulation in control treatment was 6.2% more than that in the saline treatments, whereas, Pb accumulation in the highest NaCl level, 60 mg/kg salinity treatment was 7.64% more than that of the control condition. Also, proline content of the plants was significantly increased under Cd and Pb stress. From the results of this study, it was concluded that using kale plant is recommended for phytoremediation of saline soils with 10 and 16 mg/kg Pb and Cd contents, respectively. 相似文献
23.
Maryam Haghighi 《Journal of plant nutrition》2016,39(5):655-665
For trace elements, such as copper (Cu) and zinc (Zn), the bioavailability of these elements, Cu and Zn, in biosolids is important because both are essential elements and both are potential contaminants when biosolids are land applied. A greenhouse study was conducted in factorial experiment based on a completely randomized design (CRD) with four replications on a soil treated with four rates of Cu (0, 50, 100, and 150 mg/kg) and four rates of Zn (0, 150, 300, and 450 mg/kg) on celery plants to investigate the distribution and mobility of these elements as well as growth and antioxidant changes of celery. The results of antioxidant changes were inconclusive due to irregular changes with Zn and Cu applications. However, generally the results show that Cu did not affect superoxide dismutase (SOD) or peroxidase (POD) activities in most of the treatments. On the other hand, Zn stimulated SOD and POD activities in most of the treatments. The photosynthesis rate decreased with the applications of Cu and Zn at the rates above 100 and 300 mg/kg and increased in low Cu concentration (50 mg/kg) compared to S (soil without biosolid). 相似文献
24.
Hamid Reza Jamalzadeh Maryam Akhundian Milad Kabir Hossein Khara Saeed Hajirezaee 《Aquaculture Research》2014,45(6):1090-1095
In this study, the relationships between the seminal fluid sex steroids sperm quality parameters (i.e. sperm motility and sperm production were investigated in the endangered Caspian brown trout. According to results, the variation of sex steroid concentrations was comparatively high. The seminal fluid levels of 17α‐Hydroxyprogesterone (OHP) had positive correlation with percentage and duration of sperm motility. Similar correlation was found between the seminal fluid concentration of testosterone (T) and estradiol‐17β (E2) with sperm concentration. As well as, there was no significant correlation between progesterone (P) with sperm quality indices. The significant correlation of some steroids i.e. OHP, T and E2 and sperm quality parameters of Caspian brown trout confirms the key role of these steroids in acquisition of the potential of motility during final stage of the maturation. 相似文献
25.
Trends in calving ages and calving intervals for Iranian Holsteins in Fars province,southern Iran 总被引:2,自引:2,他引:0
Maryam Ansari-Lari Maryam Rezagholi Mahdie Reiszadeh 《Tropical animal health and production》2009,41(7):1283-1288
Purpose
To determine trends in calving ages and calving interval as measures of reproductive performance in Iranian Holsteins in Fars province, southern Iran during 2000–2005. 相似文献26.
Mirbakhsh Maryam Mahjoub Masoud Afsharnasab Mohammad Kakoolaki Shapoor Sayyadi Mostafa Hosseinzadeh Saeid 《Aquaculture International》2021,29(6):2489-2506
Aquaculture International - In the present study, the white shrimp, Litopenaeus vannamei, was supplemented with the probiotic Bacillus subtilis IS02 in order to improve the larval survival rate.... 相似文献
27.
Bushra Rashid Ghazanfar Ali Khan Tayyab Husnain Sheikh Riazuddin 《Journal of Crop Science and Biotechnology》2009,12(3):135-141
We report the field evaluation of second generation of transgenic cotton expressing Bacillus thuringiensis (Bt) genes cry1Ac and cry2A under CaMV 35S promoter. Sixty-five transgenic lines were grown under RCBD design. Transgenic plants exhibited inherent ability to resist
target insect (p < 0.05 and 0.01). Morphological studies showed significant reduction in plant height making them favorable
for breeding. Yield was significantly increased for the transgenic lines. Fiber analysis showed improved gin turn out 40%
for transgenic lines in comparison to 32% for non-transformed lines. Fibre quality of transgenic lines was not affected when
compared with non transgenic lines. Inheritance pattern for transgenic lines suggests the need of further studies to understand
the complex molecular mechanisms for resistance management and biosafety studies to develop new Bt cotton varieties. 相似文献
28.
Fardin Shaluei Aliakbar Hedayati Abdolreza Jahanbakhshi Maryam Baghfalaki 《Fish physiology and biochemistry》2012,38(6):1627-1634
The objective of the study was to evaluate the efficacy of 2-phenoxyethanol (2-PE) as an anesthetic in great sturgeon under two experiments. First, fish were exposed to 0.1, 0.3, 0.5, 0.7 and 0.9?mL/L 2-PE, and time to induction (deep anesthesia) and recovery from anesthesia were measured. At concentration of 0.1?mL/L, 2-PE failed to induce deep anesthesia in fish, whereas at concentrations of 0.7 and 0.9?mL/L, all the fish were anaesthetized within 3?min of exposure. For assessing the impact of effective concentrations of 2-PE on physiological responses of great sturgeon, hematological indices, plasma metabolites, electrolytes, enzymes and cortisol levels were measured. The use of 2-PE induces a significant increase in RBC values at 0.3?mL/L concentration and a parallel increase in hemoglobin and hematocrit values. 2-PE anesthesia had no effect on WBC, MCV, MCH and MCHC levels when compared to control group. Serum glucose, cholesterol and cortisol levels were significantly high in 0.3 and 0.5?mL/L 2-PE. Moreover, AST levels were increased in fish exposed to the 0.3?mL/L 2-PE comparing with the control group (P?<?0.05). There were no significant differences in serum levels of total protein, triglycerides, ALP, ALT, Cl?, Na+, K+, Ca2+ and Mg2+. In this study, alteration in hematological and serum biochemical indices was time-dependent. This study demonstrates that rapid induction of deep anesthesia with a relatively high concentration of 2-PE (0.7 and 0.9?mL/L) was associated with the lowest effects on the hematological and serum biochemical indices in great sturgeon and therefore would be recommended as eligible doses for hematological studies in this species. 相似文献
29.
Isa Esfandiarpour-Borujeni Seyed Javad Hosseinifard Hossein Shirani Maryam Zeinadini Ali Asghar Besalatpour 《Communications in Soil Science and Plant Analysis》2018,49(12):1474-1490
The main objective of this study was to evaluate the potential use of a hybrid Genetic Algorithm-Artificial Neural Network (GA–ANN) method for predicting pistachio yield and for identifying the determinant factors affecting pistachio yield in Rafsanjan region, Iran. A total of 142 pistachio orchards were selected randomly and soil samples were taken at three depths. Besides, water samples and leaves from branches without fruit were taken in each sampling point. Management information and pistachio yields were achieved by completing a questionnaire. Primarily, 58 variables affecting pistachio yield were measured, and then 26 out of them were selected by minimizing mean square error (MSE) using a feature selection (FS) method. The results showed that the accuracy of the method was acceptable. Furthermore, the sensitivity analysis showed that the main determinant features affecting the pistachio yield were the irrigation water amount, leaf phosphorus, soil soluble magnesium, electrical conductivity (EC), and leaf nitrogen. 相似文献
30.
Effects of forest harvesting on runoff and sediment characteristics in the Hyrcanian forests,northern Iran 总被引:1,自引:0,他引:1
Maryam Etehadi Abari Baris Majnounian Arash Malekian Meghdad Jourgholami 《European Journal of Forest Research》2017,136(2):375-386
Loss of canopy cover by forest harvesting generally increases the average surface runoff volume and sediment. Selective cutting (single and group selection method) is the most usual forest harvesting method in the Hyrcanian forests in the north of Iran. The purpose of this study is to find the effect of selective logging technique on the hydrological behavior of runoff and sediment in the Kheyrud forests located in northern Iran over 1 year. Four treatments were implemented: natural forest without harvesting (C), forest with selective harvesting (H) and area without canopy cover (WC) and skid trail (S). Three types of data were measured in each plot including soil chemical and physical properties, runoff and sediment load after each rainfall. The results indicate significant differences (P ≤ 0.05) in runoff generation and sediment production with respect to the treatments cover. The runoff in all treatments showed relatively similar response to rainfall, while the highest runoff and sediment were observed in skid trails, and the area without canopy cover (1.13 and 0.62 mm, and 1.2 and 0.51 g m?2), averagely. In contrast, the natural forest without harvesting and the forest with selective harvesting treatments exhibited the lowest amounts of runoff (0.2 and 0.44 mm) and sediment (0.1 and 0.17 g m?2), averagely. Implementation of low logging technique was useful to control the effects of logging on the runoff and sediment yield. 相似文献