Effects of concentration and propagule age on the efficacy of gibberellic acid for breaking dormancy in potato minitubers     

Kh. Salimi  M.B. Hosseini  R. Tavakkol-Afshari  P.C. Struik 《The Journal of Horticultural Science and Biotechnology》2013,88(6):461-464

Summary

The effects of a post-harvest application of gibberellic acid (GA₃) at various concentrations (0, 10, 25, 50, or 100 mg l^–1) and for different periods of incubation (1, 2, or 3 h) on the breaking of dormancy and on sprouting in potato (Solanum tuberosum L., cv. Marfona) minitubers of two ages (freshly-harvested or 1 week after harvest) were investigated. Compared with untreated, control minitubers, GA₃-treated minitubers showed a significantly shorter period of dormancy (46 d), especially when the minitubers were treated at all concentrations immediately after harvest (41 d). GA₃ treatment had a greater effect on dormancy in freshly-harvested minitubers than in 1 week-old minitubers, probably because of the reduced uptake of GA₃ solution after skin-set. At lower concentrations of GA₃, the period of dormancy tended to decrease the longer the minitubers were immersed in the GA₃ solution. In contrast, at higher concentrations of GA₃, the duration of immersion only had an effect up to 2 h and any longer immersion was ineffective. The average number of sprouts was not affected by GA₃ concentration, or by the time of incubation, but was significantly higher for freshly-harvested minitubers (1.4) than for 1 week-old minitubers (1.2). The lengths of the sprouts increased with an increase in GA₃ concentration, especially in freshly-harvested minitubers. Consequently, immersing freshly-harvested potato minitubers in a low concentration of GA₃ (up to 25 mg l^–1) for up to 3 h effectively shortened the period of dormancy and led to the formation of sprouts of optimum length.  相似文献   

Tissue distribution of infectious pancreatic necrosis virus serotype Sp in naturally infected cultured rainbow trout,Oncorhynchus mykiss (Walbaum): an immunohistochemical and nested‐PCR study     

N Ahmadi  A Oryan  M Akhlaghi  A Hosseini 《Journal of fish diseases》2013,36(7):629-637

This study investigates the occurrence and distribution pattern of infectious pancreatic necrosis virus (IPNV) within the pancreas, liver, kidney and spleen of naturally infected cultured rainbow trout, Oncorhynchus mykiss (Walbaum), using immunohistochemistry (IHC). A nested PCR was also employed to confirm the presence of the virus in the pooled tissues of the specimens. All the examined tissues except spleen were immunohistochemically positive for IPNV, but staining intensity and distribution pattern varied. The kidney tubules had the most intense and widespread staining by IHC, indicating a specific tissue tropism at least for this particular serotype. The nucleotide sequence had the greatest identity with the Sp serotype confirming the presence of the nucleic acid of IPNV in the pooled tissues. Based on the present findings, it could be concluded that the absence of lesions consistent with infectious pancreatic necrosis (IPN) disease in the H&E‐stained sections cannot rule out the presence of the IPNV, and the use of an alternative rapid confirmatory method such as IHC with formalin‐fixed, paraffin‐embedded tissue sections is helpful for the final diagnosis of IPN in rainbow trout.  相似文献   

Cotton yarn engineering via fuzzy least squares regression     

S. Fattahi  S. M. Taheri  S. A. Hosseini Ravandi 《Fibers and Polymers》2012,13(3):390-396

Modeling of yarn and fiber properties has been a popular topic in the field of textile engineering in recent decades. The common method for fitting models has been to use classical regression analysis, based on the assumptions of data crispness and deterministic relations among variables. However, in modeling practical systems such as cotton spinning, the above assumptions may not hold true. Prediction is influential and we should therefore attempt to analyze the behavior and structure of such systems more realistically. In the present research, we investigate a procedure to provide a soft regression method for modeling the relationships between fiber properties, roving properties, and yarn count as independent variables and yarn properties as dependent (response) variable. We first selected the effective variables by multivariate test (mtest) and then considered fuzzy least squares regression for evaluating relationship between cotton yarn properties such as tensile, hairiness, unevenness and fiber properties that were measured by HVI system. We also used mean of capability index (MCI) to evaluate the goodness of fit of the fuzzy regression models. The results showed that the equations were significant at very good MCI levels.  相似文献   

1980-2009年西藏西北部潜在蒸散时空分布特征及其影响因素   总被引：3，自引：0，他引：3  

卓嘎  尼玛央珍  唐小萍 《干旱区研究》2016,(4):698-707

通过分析西藏西北部潜在蒸散量的时空分布以及影响潜在蒸散的气候因素.结果表明:①西藏西北部潜在蒸散呈现从西北向东南减少的分布特征,最大潜在蒸散出现在夏季,春季次之,冬季最小.近30 a来,除冬季潜在蒸散呈略微增加趋势外,其余均呈减少趋势.气温、相对湿度和降水量呈增加趋势,平均风速和日照时数呈减少趋势;潜在蒸散与气温、风速、日照时数呈正相关,与相对湿度、降水量呈负相关.②影响潜在蒸散的主要气象要素为相对湿度、平均气温和日照时数,风速对冬季潜在蒸散的影响最为显著;近30 a来,风速减小、日照时数减少、相对湿度增加是导致潜在蒸散量减少的主要气象影响因子.西藏西北部地区潜在蒸散的变化存在“蒸发悖论”现象,即在气温升高[0.55℃·(10a)-1]的背景下,潜在蒸散呈下降趋势[10.02 mm ·(10a)-1].  相似文献   

Identification of low lectin mutants in soybean     

M. A. George    S. V. Bhide    R. J. Thengane    G. H. Hosseini    J. G. Manjaya 《Plant Breeding》2008,127(2):150-153

Lectin is one of the known antinutritional factors that deteriorate the soybean protein quality and development of cultivars with low lectin content will help to improve nutritional quality of soybean [Glycine max (L.) Merrill]. Therefore, attempts were made to induce mutations for low lectin content in the cultivar ‘MACS 450’. Soybean cultivar ‘MACS 450’ was subjected to combination treatments of γ‐rays and ethyl methane sulphonate (EMS) with an objective to induce variability for low lectin content. The treatments of different combinations of γ‐rays and EMS were 50 Gy + 0.2% EMS, 50 Gy + 0.4% EMS, 100 Gy + 0.2% EMS and 100 Gy + 0.4% EMS. Of the 3200 treated M₁ seeds sown, 16 400 M₂ plants were raised. In M_2, 72 plants were identified for low lectin content [<40 × 10⁵ haemagglutination unit (HAU)/mg] and were carried up to M₅ generation. In M₅ generation, lectin content in ‘MACS 450’ was 39.23 to 50.0 × 10⁵ HAU/mg, and was compared with the nine true breeding lines identified having low lectin content, ranging from 2.3 × 10⁵ to 27.46 × 10⁵ HAU/mg. Three mutants were found to possess very low lectin content (ranging from 2.0 × 10⁵ to 3.0 × 10⁵ HAU/mg). Thus, the identified mutant lines with low lectin content will greatly improve soybean protein quality, thereby reducing financial burden on the soybean industry for processing soybean meal and also making it suitable for human consumption. All the mutants showed normal seed development, having soluble protein content similar or higher than that in the parent (32.0 mg/ml). This indicates that the change in lectin content does not have any negative impact on the plant growth and protein content.  相似文献   

Alleviation of Salinity Stress by Vermicompost Extract: A Comparative Study on Five Fennel Landraces     

Abdollah Beykkhormizi  Siavash Hosseini Sarghein  Mohammad Reza Sarafraz Ardakani  Seyed Mohammad Moshtaghioun  Seyed Mousa Mousavi Kouhi 《Communications in Soil Science and Plant Analysis》2018,49(17):2123-2130

In the present study, interaction between salinity (0, 40, 80, 120 mM NaCl) and vermicompost extract (VCE) on five fennel landraces (Urmia, Mashhad, Shiraz, Boushehr, Isfahan) was investigated in a factorial experiment as completely randomized design to find the best salt-tolerant landrace and potential alleviating role of VCE. Results showed that Boushehr and Isfahan were the most tolerant and sensitive landrace to salinity, respectively. Application of VCE improved germination and growth of salt-treated fennels. The amylase activity of fennels was not affected by salinity and not improved by VCE. While sodium (Na⁺) content of root and shoot of all salt-treated fennels increased, their potassium (K) content decreased. Under salinity stress, root K content of VCE-amended landraces was more than that of not amended ones. VCE also caused an increase in calcium (Ca) content of root of salt-treated Shiraz and Urmia landraces. In conclusion, VCE can alleviate adverse effects of salinity stress on fennel.  相似文献   

Effect of dietary taurine and methionine supplementation on growth performance,body composition,taurine retention and lipid status of Persian sturgeon,Acipenser persicus (Borodin, 1897), fed with plant‐based diet          下载免费PDF全文

S.M. Hoseini  S.A. Hosseini  S. Eskandari  M. Amirahmadi 《Aquaculture Nutrition》2018,24(1):324-331

The aim of this study was to investigate the effects of dietary taurine and methionine on Persian sturgeon (Acipenser persicus) fed with plant‐based diets. To this purpose, sturgeons were fed with either of methionine + taurine‐supplemented (MT), without taurine supplementation (M) or without methionine supplementation (T) diets. Growth performance, body composition, tissue amino acids and serum glucose and lipids were studied at the end of the experiment. Results showed that the treatments T and MT had similar growth performance and feed efficiency, which were significantly higher than the treatment M. Dietary taurine and methionine significantly altered carcass and liver taurine and methionine contents. The highest serum glucose was observed in the treatment M and the lowest in treatment MT. Serum cholesterol and triglyceride levels in the treatments T and MT were similar and significantly higher than those of the treatment M. This study showed that Persian sturgeon needs taurine supplementation when fed with plant‐based diets, but the supplemented level seems to be lower than those of the other species. Taurine has hypoglycaemic and lipidogenesis effects on Persian sturgeon. However, further studies are required to illustrate taurine and methionine metabolism in Persian sturgeon.  相似文献   

mRNA abundance changes during in vitro oocyte ageing in African catfish Clarias gariepinus (Burchell, 1822)          下载免费PDF全文

Azadeh Mohagheghi Samarin  Sabine Sampels  Tomas Policar  Marek Rodina  Nima Hematyar  Azin Mohagheghi Samarin 《Aquaculture Research》2018,49(2):1037-1045

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Wicking phenomenon in polyacrylonitrile nanofiber yarn     

Mahbube Sadat Musavi Jad  Seyed Abdolkarim Hosseini Ravandi  Hossein Tavanai  Razieh Hashemi Sanatgar 《Fibers and Polymers》2011,12(6):801-807

The aim of this paper is to investigate vertical wicking in polyacrylonitrile (PAN) electrospinning nanofiber yarn using image analysis. Colored liquid rising phenomenon into the yarn and the distance of liquid rise were determined as a function of time. The kinetics of capillary rise follows the Lucas-Washburn equation. The results show that capillary rise rate coefficient is being reduced with increasing yarn twist, due to the reduction of continuity and size of capillaries. Increasing heat treatment stretch from 0 % (draw ratio=1) to 50 % (draw ratio=1.5) increases the capillary rise rate coefficient, due to the more homogeneity of capillary spaces in the yarn structure and increasing heat treatment stretch from 50 to 100 % (draw ratio=2) reduces capillary rise rate coefficient, because of the low capillary length. The present study indicates that an appropriate choice in production parameters of nanofiber yarn is all important in obtaining the desired properties of capillary rise.  相似文献   

Forest fire effects in beech dominated mountain forest of Iran     

Abbas Banj Shafiei  Moslem Akbarinia  Gholamali Jalali  Mohsen Hosseini 《Forest Ecology and Management》2010

Most of world's forests of different climates have a history of fire, but with different severities. Fire regimes for broadleaf deciduous forests have return intervals that vary from many decades (or less) to centuries (or more). Iran has a total of 1.2 million ha of temperate forest in the north, where fires burn about 300–400 ha annually. This study focused on the impact of fire on forest structure, tree species quality, and regeneration composition (specially beech) in the Chelir forest of northern Iran. The results showed that forest fires changed the structure and had different effects on tree species composition between burned and control areas. Thin barked species such as oriental beech (Fagus orientalis Lipsky) and coliseum maple (Acer cappadocicum Gled.) have been affected more than those with thick bark, like hornbeam (Carpinus betulus L.) and chestnut-leaved oak (Quercus castaneifolia C.A. Mey). The density of oriental beech regeneration in the unburned area was greater than in the burned area, while the quantity of regeneration of hornbeam, coliseum maple and velvet maple (Acer velutinum Boiss) was higher in burned area. Forest fire had a greater effect on oriental beech quality, and changed regeneration composition in the burned area. Fire prevention activities should be considered as a silvicultural treatment for preserving these valuable forests.  相似文献