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101.
Roya Jafari Mohsen Hossein-Alizadeh Hasan Rezaii-Moghadam 《Communications in Soil Science and Plant Analysis》2017,48(8):908-919
Saturated hydraulic conductivity (Ksat) is regarded as a key soil physical variable to determine soil infiltration rate, percolation depth and other hydrological processes. The purpose of this study was to determine the best soil sampling’s ring size for measuring Ksat. For this purpose, 25 rings with five different diameters (2, 3, 4, 5 and 6 inch) and with the same depth of 20 cm (five replicates) were hammered in close vicinity to each other into the ground of undisturbed loess deposits of a small farm to measure Ksat and bulk density. Hydraulic conductivity was measured at three constant loads of 22, 27 and 32 cm. The results showed that the ring with the internal diameter of 6 inches had the minimum variation coefficient and maximum Ksat for all the three hydraulic heads. In addition, the bulk density of this ring size was less than the other rings. 相似文献
102.
Mohammad Golbashy Iraj Allahdadi Hossein Nazokdast Morteza Hosseini 《Archives of Agronomy and Soil Science》2017,63(1):84-95
The present study describes the preparation and characterization of montmorillonite-urea nanocomposites (Mt-Ur) using aqueous suspension technique at various stirring times and different ratio of montmorillonite to urea (Mt/Ur) via an impure and domestic montmorillonite (Mt), without the application of any chemical reagents and high-energy-demand process (environmentally friendly). The intercalation of urea into Mt interlayer was clearly demonstrated by a significant expansion of d001 spacing (interlayer space of Mt) from 1.23 to 1.71 nm which has not yet been reported by aqueous suspension technique. Analyses performed by Fourier transform-infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA) and X-ray diffraction (XRD) also confirmed the effectiveness of this simple process to intercalate the urea into clay lamella. The release pattern demonstrated that the nanocomposite had a slow-release behaviour for urea dissolution. The results also suggested that the Mt type applied in the current study, in a 1:20 Mt/Ur ratio and stirred for 1 h, possessed desirable ecological and economic efficiency in the production of slow-release urea fertilizer due to the application of the impure and domestic clay which is of very low-cost and eco-friendly. Nevertheless, urea was fully intercalated into the interlayer of clay by a simple technique and with a good slow-release behaviour. 相似文献
103.
Parisa Koobaz Ghasem Hosseini Salekdeh Foad Moradi Hossein Hadavand 《Journal of plant nutrition》2017,40(4):574-583
Four-day-old seedlings of spring wheat (Triticum aestivum L. cv. Marvdasht) can tolerate severe dehydration and recover after re-watering. In order to clarify tolerance mechanism, in a completely randomized design, the seedlings were exposed to drought by complete water cessation for 10 and 20 days, followed by re-watering for 3 and 7 days. Upon dehydration, the activity of α-amylase increased whereas growth parameters; photosynthetic pigments; and the activities of lipoxygenase, indole acetic acid (IAA) oxidase, and ascorbate peroxidase (APX) decreased. The activity of APX and the expression of its gene, however, increased after re-watering. Prolonged dehydration was also accompanied by increase in sucrose, soluble proteins, fructans, and certain amino acids, e.g. proline, glutamine, and valine. The results indicated that during dehydration, 4-day-old wheat seedlings shifted their energy expenditure from basal metabolism to withstand water deficiency via lowering the activity of membrane-damaging enzymes and enhancing the production of osmoprotectants. 相似文献
104.
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106.
Saber Jelokhani-Niaraki Majid Esmaelizad Morteza Daliri Rasoul Vaez-Torshizi Morteza Kamalzadeh Mohsen Lotfi 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):243-247
The A Iran 05 foot-and-mouth disease virus (FMDV) subtype was detected in Iran during 2005 and has proven to be highly virulent. This study was undertaken to focus on molecular and phylogenetic analysis of 3A and 3B coding-regions in the A Iran 05 field isolate. To assess the genetic relatedness of A Iran 05 isolate the nucleotide and predicted amino acid sequences of the 3AB region of type A FMDV isolates were compared with twenty previously described type A FMDV isolates. The phylogenetic tree based on the 672 bp 3AB gene sequences of type A FMDV from thirteen different locations clustered them into five distinct lineages. The A Iran 05 isolate clustered in lineage A along with four type A variants and was closely matched with viruses isolated in Turkey and Pakistan during 2005~2006. The number of protein sequence differences exhibited by each of the isolates revealed that A Iran 05 isolate contains three amino acid substitutions at positions 47 and 119 of 3A and 27 of the 3B coding region. The nucleotide identity between A Iran 05 and the other four isolates of lineage A was estimated to be 98%. 相似文献
107.
Polyculture of western white shrimp,Litopenaeus vannamei Boone, 1931 with Grey mullet,Mugil cephalus Linnaeus, 1758 controls external parasites of western white shrimp 下载免费PDF全文
Seyyed Hossein Hosseini Aghuzbeni Saeed Hajirezaee Hossein Khara 《Aquaculture Research》2016,47(9):2983-2988
The main aim of this study was to examine the effects of a polyculture system on the control of the external parasites of western white shrimp, Litopenaeus vannamei. To this end, the western white shrimp postlarvae (PLs) were stocked in nine earthen ponds (600 m2) at a density of 20 PLs m?2 and reared for 4 months. After 40 days of shrimp stocking, Mullets, Mugil cephalus, were stocked at various densities including: control (0 fish/100 m2 pond), treatment 1 (T1: 2 fish/100 m2 pond) and treatment 2 (T2: 4 fish/100 m2 pond). Over the course of the experiment, the external parasites of shrimps were investigated by the preparation of a wet mount from the gill tissue. Based on the obtained results, totally two genera of protozoan parasites, i.e. Zoothamnium sp. and Epistylis sp., were identified over the course of the experiment. In all experimental groups, the incidence and abundance of Zoothamnium sp. was significantly higher than Epistylis sp. (P < 0.05). Also, mean incidence per cent and mean abundance of Zoothamnium sp. and Epistylis sp. were significantly lower in the polyculture treatments (T1 and T2) compared to the monoculture group (control) (P < 0.05). Throughout this experiment, the total organic matter (TOM %) content of the bottom sediments and biological oxygen demand (BOD5 mg L?1) of water samples in the polyculture ponds were significantly lower than the monoculture group (P < 0.05). In contrast, the polyculture ponds had a higher concentration of water dissolved oxygen (O2 mg L?1) compared to the monoculture (P < 0.05). In conclusion, our results show that mullet as a secondary farmed species can reduce indirectly the parasitic pollution of western white shrimp probably through reducing the total organic matters in water and sediments and improving the water quality parameters. 相似文献
108.
Seyed Saeid Hojjat 《Russian Agricultural Sciences》2013,39(2):134-142
One hundred lentil genotypes accessions of Mashhad Lentil Collection (MLC) were evaluated at Chenaran, Iran with three planting dates [10 Oct., 10 Nov. (fall) and 28 Mar. (spring) during 2008/09 growing seasons]. Evaluation based on winter survival percentage showed that in 2008/09 growing season, percentage of highly tolerant, tolerant, moderately tolerant, moderately susceptible and susceptible genotypes were 22, 61, 16, 1 and 0 respectively. In the first planting date more than 50% of genotypes were ranked as highly tolerant, however it was decreased to 12% and 5% of genotypes in the second and third planting dates, respectively, in this year. According to the fall plantings data, the length of growth duration of samples in fall plantings were 2.3 times higher than spring planting, and also in the first planting that was 5, 25 and 255 percent more than 2nd and 3rd planting dates, respectively. The height of fall plants were more than spring plants and in the first year fall planting genotypes were about 38% taller than the same planting. The number of pod per plant in fall planting was 2 times higher than spring planting. More than 22% of accessions had 125 pods per plant in 1st and 2nd planting in this year. In the 2008/09 growing seasons the yield of lentil genotypes in fall planting were more than 4 and about 2 times of spring planting, respectively. In the 2008/09 growing seasons 39% of spring planting samples produced less than 50 gr/m2 seed yield. It seems that the improvement of seed yield in the fall planting were due to suitable winter survival of plants fallowed by better usage of rainfall and escaping from drought and heat stress of the end of spring. Results showed that there were some cold tolerant accessions in MLC and it is possible to provide cold tolerant cultivars for fall planting in Mashhad conditions. 相似文献
109.
Shahla Hosseini Bai Fangfang Sun Zhihong Xu Timothy J. Blumfield Chengrong Chen Clyde Wild 《Journal of Soils and Sediments》2012,12(5):653-662
Purpose
It is anticipated that global climate change will increase the frequency of wildfires in native forests of eastern Australia. Understorey legumes such as Acacia species play an important role in maintaining ecosystem nitrogen (N) balance through biological N fixation (BNF). This is particularly important in Australian native forests with soils of low nutrient status and frequent disturbance of the nutrient cycles by fires. This study aimed to examine 15N enrichment and 15N natural abundance techniques in terms of their utilisation for evaluation of N2 fixation of understorey acacias and determine the relationship between species ecophysiological traits and N2 fixation. 相似文献110.
Shahla Hosseini Bai Timothy J. Blumfield Zhihong Xu Chengrong Chen Clyde Wild 《Journal of Soils and Sediments》2012,12(3):386-395