Evaluation of hemolymph biochemical properties,clearance rate,bacterial microbiota and expression of HSP genes of gulf pearl oyster Pinctada radiata in response to salinity changes     

Jahromi  Saeid Tamadoni  Pourmozaffar  Sajjad  Rameshi  Hossein  Gozari  Mohsen  Nahavandi  Reza 《Fisheries Science》2020,86(6):1055-1065

Fisheries Science - Hypo-salinity exposure is a serious concern for bivalve aquaculture, with profound effects on the animals’ physiological condition. The present study aimed to evaluate the...  相似文献   

Evaluation of some haemolymph biochemical properties and F‐cell prevalence in hepatopancreas of white leg shrimp (Litopenaeus vanammei) after fed diets containing apple cider vinegar and propionic acid     

Sajjad Pourmozaffar  Saeid Tamadoni Jahromi  Hossein Rameshi  Mohsen Gozari 《Aquaculture Research》2019,50(11):3435-3443

The present study aimed to evaluate the effect of dietary ACV (apple cider vinegar) and PA (propionic acid) supplementation on some biochemical properties of haemolymph and fibrillar cell (F‐cell) number in the hepatopancreas of shrimp. Five different diets supplemented with 0%, 1%, 2%, 4% ACV and 0.5% PA diets were fed to Litopenaeus vanammei. Some biochemical parameters of haemolymph (cortisol, alkaline phosphatase, albumin, urea, uric acid, creatinine, phosphorus, total hemocyte count) and prevalence of F‐cell in hepatopancreas were examined after 60 days feeding trial. The albumin concentration and total hemocyte count in 2% and 4% ACV and PA groups were significantly higher than those of other groups (p < .05). Moreover, the highest phosphorus concentration was detected in shrimp fed 4% ACV and PA experimental diets (p < .05). No significant differences in haemolymph cortisol, urea, uric acid, creatinine, alkaline phosphatase and tubule area were observed among the experimental groups (p > .05). 2% ACV group showed more F‐cell number in hepatopancreas than other groups while the reduction in F‐cell number was observed in the PA group. Based on these observations, the tested ACV and PA diets remarkably exhibited positive impacts on nutritional value and they may be a potential for adding to shrimp diet.  相似文献   

Risk assessment of pesticides in paddy fields and the Safīdrūd River in Gīlān,Iran     

Abolghasem Alighardashi  Sajjad Jalali  Mostafa Nazem Bokaei  Hosein Asefi 《Paddy and Water Environment》2017,15(2):371-380

Safīdrūd River is the longest river in northern Iran and serves 2.5 million people as a water resource for drinking, irrigation, pisciculture, and recreation. To evaluate the fate of pesticides in paddy fields on the Safīdrūd river bank and the Safīdrūd basin, a comprehensive model is developed in this paper to predict pesticide concentration. The model includes degradation and sorption to soil in paddy field and two-dimensional turbulent with degradation in river. To investigate the effects of pesticides on health, an inclusive risk assessment is defined by parameters such as the maximum annual prediction environmental concentration and mean prediction environmental concentration of pesticides in the intake zone of the Safīdrūd river for the Rasht water treatment plant. The risk quotient of all pesticides were higher than 1 (i.e., for Diazinon it was calculated to be 670) which indicate high risk in the Rasht potable water and can potentially cause various digestive cancers and other refractory and mutagenic diseases. As a result, it is necessary to codify the global planning of pesticide application in the paddy fields by the local government.  相似文献   

The low down on association mapping in hexaploid wheat (Triticum aestivum L.)     

Muhammad Sajjad  Sultan Habibullah Khan  Abdul Mujeeb Kazi 《Journal of Crop Science and Biotechnology》2012,15(3):147-158

The past few decades have witnessed hundreds of family-based linkage studies mapping for numerous traits but only a limited number of QTLs were actually cloned, tagged, or used for marker-assisted selection. Although providing valuable information, this conventional approach cannot be scaled up to underpin the incredible amount of phenotypic variation in the form of 266, 589 hexaploid wheat accessions maintained in public germplasm collections. Association mapping has recently emerged as an alternative and more powerful mapping approach where a natural population is surveyed to determine marker-trait associations using linkage disequilibrium (LD). After its first application for milling quality in 2006, association mapping studies in hexaploid wheat are being extended to tag yield traits, protein quality, and tolerance to biotic and abiotic stresses. Advances in genotyping technology and statistical approaches greatly accelerated the shift from conventional linkage-based mapping to LD-based association mapping. Association mapping stands out because of simultaneous utilization of a large number of ex situ-conserved natural variation due to historical recombination events accumulated over centuries.  相似文献   

Relative significance of soil and nitrogenous fertilizer in nitrogen nutrition and growth of wetland rice (Oryza sativa L.)     

F. Azam  M. Ashraf  A. Lodhi  M. I. Sajjad 《Biology and Fertility of Soils》1991,11(1):57-61

Summary A pot experiment was conducted to compare the yields from five commercially cultivated varieties (Bas-198, Bas-370, Bas-Pak, Bas-385, and IR-6) of rice (Oryza sativa L.) and to establish the relative significance of soil N and fertilizer N (¹⁵N-labelled ammonium sulphate) in affecting crop performance. Another aim was to study the interaction of fertilizer N and soil N as influenced by different rice varieties. Among the five varieties tested, Bas-Pak gave the maximum dry matter and N yield. The N-use efficiency (percentage of applied N taken up by the plants) of different varieties ranged between 33.7 and 43.7%, Bas-Pak being the most efficient. Significant losses of fertilizer N occurred from the soil-plant system. The maximum N loss (52.1% of applied N) was observed with IR-6 and the minimum loss (39.2%) with Bas-Pak. A substantial increase in the uptake of soil N following the application of fertilizer and an interaction between the two N sources were observed with all varieties except Bas-385. The interaction was attributed to greater root proliferation following the application of fertilizer. It was concluded that a varietey with greater potential to use soil N is likely to give a better yield and that, of the two N sources, the availability of soil N was more important in determining the yield performance of different varieties of rice.  相似文献   

Facultative apomixis and chromosome doubling are sources of heterogeneity in citrus rootstock trials: Impact on clementine production and breeding selection     

Sajjad Hussain  Franck Curk  Patrick Ollitrault  Raphaël Morillon  François Luro 《Scientia Horticulturae》2011

All commercial citrus rootstocks are polyembryonic and propagated by seeds. Although these seeds produce uniform plant material most of the time, zygotic or polyploid citrus seedlings may arise. The aim of this study was to understand how zygotic or tetraploid rootstock could affect a citrus rootstock selection field trial. A trifoliate orange selection field trial, which was planted in 1974 and grafted with clementine, was re-investigated with respect to the presence of rootstocks that were not true-to-type. Among the 288 trees investigated, flow cytometry identified 2.4% of rootstocks as tetraploid and SSR markers indicated that 6.6% were zygotic. Yield data showed that the presence of tetraploid rootstock dramatically decreased (by about 45%) clementine fruit production. However, zygosity did not always affect fruit production and a range of effects were observed, from a slight increase in production to a 24% decrease. Exclusion of non-true-to-type genotypes from the production analysis indicated that the best candidate for rootstock was a clone previously ranked in the middle of the 32 rootstocks under evaluation. However, the presence of zygotic rootstock did not appear to cause any significant differences in fruit quality during the first 5 years of the investigation, which suggests that non-true-to-type plants cannot be identified by fruit quality parameters. This study indicates that tetraploid and zygotic rootstocks have a strong impact on citrus fruit production in orchards, and removal of off-type seedlings is required prior to planting in any agronomic trial.  相似文献   

Lithogenic and anthropogenic impacts on soil surface magnetic susceptibility in an arid region of Central Iran     

Shamsollah Ayoubi  Sajjad Amiri  Samaneh Tajik 《Archives of Agronomy and Soil Science》2013,59(10):1467-1483

In this study, natural and anthropogenic factors affecting the spatial distribution of topsoil mass magnetic susceptibility (χlf) were investigated in an arid region in Isfahan province, central Iran. A total of 100 surface (0–5 cm) soil samples were collected, and the χlf value of the soil samples was measured. High values of χlf in the east and northeast parts of the area indicated the occurrence of hilly igneous rocks and pediment geomorphic surface, enriched by ferrimagnetic minerals. In order to investigate the effects of human activities, multivariate geostatistics was applied to the results on the concentrations of eight heavy metals in surface soil samples. The results indicated that the spatial variability of second factor extracted by factor analysis, with high contribution of Zn, Pb and Cu, was well in agreement with the distribution of urban and industrial sites. This implied that magnetic particles accompanying the heavy metal emissions have increased χlf in the topsoil of the west of the area studied. Multiple linear regression analysis of χlf with studied factors revealed that the developed model explained about 64% of total variability in χlf in the studied area; and geology was identified as the most important controlling factor.  相似文献   

Effects of seed priming with plant growth-promoting rhizobacteria on wheat yield and soil properties under contrasting soils     

Muhammad Akbar  Nazir Aslam  Tayyaba Khalil  Shamim Akhtar  Ejaz Hussain Siddiqi  Muhammad Sajjad Iqbal 《Journal of plant nutrition》2013,36(17):2080-2091

In the present investigation, different strains of Plant growth-promoting rhizobacteria (PGPR), namely Bacillus megaterium, Pseudomonas fluorescens and Bacillus subtilis were evaluated for their growth-promoting effects on wheat as well as on soil properties under field conditions at two different sites having sandy loam and silt loam type of soils. PGPR strains were evaluated either singly or in consortia. Amongst all the treatments, wheat inoculated with consortia was found most effective as it increased grain yield up to 53% over control in silt loam soil, whereas, corresponding effects in sandy loam soil were less pronounced as an increase of 31% was observed in corresponding treatments, respectively. Enhanced effects on soil properties were also more intense in silt loam as there was an increase of 205% organic matter as against sandy loam soil where this value was 110%.  相似文献   

Availability of soil and fertilizer nitrogen to wheat (Triticum aestivum L.) following rice-straw amendment     

Azam  F.  Ashraf  M.  Lodhi  Asma  Sajjad  M. I. 《Biology and Fertility of Soils》1990,10(2):134-138

Summary A pot experiment was conducted to study the N availability to wheat and the loss of ¹⁵N-labelled fertilizer N as affected by the rate of rice-straw applied. The availability of soil N was also studied. The straw was incorporated in the soil 2 or 4 weeks before a sowing of wheat and allowed to decompose at a moisture content of 60% or 200% of the water-holding capacity. The wheat plants were harvested at maturity and the roots, straw, and grains were analysed for total N and ¹⁵N. The soil was analysed for total N and ¹⁵N after the harvest to determine the recovery of fertilizer N in the soil-plant system and assess its loss. The dry matter and N yields of wheat were significantly retarded in the soil amended with rice straw. The availability of soil N to wheat was significantly reduced due to the straw application, particularly at high moisture levels during pre-incubation, and was assumed to cause a reduction in the dry matter and N yields of wheat. A significant correlation (r=0.89) was observed between the uptake of soil N and the dry matter yield of wheat with different treatments. In unamended soil 31.44% of the fertilizer N was taken up by the wheat plants while 41.08% of fertilizer N was lost. The plant recovery of fertilizer N from the amended soil averaged 30.78% and the losses averaged 45.55%  相似文献   

Effect of Fixed Media Surface Area on Biofouling and Nutrients Removal in Fixed Film Membrane Bioreactor Treating Sewage at Medium and High Fluxes     

Muhammad Zeeshan  Sajjad Haydar  Shamas Tabraiz 《Water, air, and soil pollution》2017,228(9):377

This study investigates effects of fixed film surface area increment on removal efficacy and biofouling in membrane bioreactor (MBR). For this purpose, a lab-scale membrane bioreactor was used. Domestic wastewater was fed into it. Three different trials were conducted at different fluxes; 15, 20, and 25 L/m²/h (LMH). Every trial was conducted using four different scenarios by varying surface area of fixed media viz. 0, 100, 150, and 200 m²/m³. Removal of pollutants viz. chemical oxygen demand (COD), biochemical oxygen demand (BOD), total organic content (TOC), total Khjdel nitrogen (TKN), and phosphorous was studied. In addition, cake resistance, pore resistance, and total resistance were also observed for aforementioned scenarios. The results demonstrated that pollutant removal efficiencies increased as the surface area per unit volume of bioreactor was increased. Conversely, the removal efficiency decreased with increase in the fluxes. In the case of biofouling, it increased while increasing the surface area or flux. The fixed media surface area increments proved beneficial in terms of removal efficiencies but at the cost of reduced operation time of MBR.  相似文献