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1.
The important root characteristics of root length density (RLD) and root mass density (RMD) generally differ among irrigation managements and potato cultivars. The objective of this study was to investigate the RLD and RMD variations and their functional relationships with gross potato tuber yield for two commercial potato cultivars, Agria and Sante, under different irrigation strategies. Full irrigation and water‐saving irrigation strategies, deficit and partial root drying irrigations, were applied statically (S) and dynamically (D) based on daily crop evapotranspiration. Results showed that SPRD had significantly greater RLD (3.64 cm/cm3) and RMD (132.7 μg/cm3) than other irrigation treatments. Between the potato cultivars, Agria had significantly larger values of RLD (3.50 cm/cm3) and RMD (138.7 μg/cm3) than Sante. The functional relationship between the root growth characteristics and tuber yield showed that under water‐saving irrigations, Agria increased root mass at the expense of gross tuber yield but Sante increased root mass to maintain larger gross tuber yields. However, Agria produced more roots and gross tuber yield than Sante, and it is concluded that Agria is a more drought‐tolerant potato cultivar, which is recommended for tuber production in regions where water might be scarce. It was shown that larger root production in potatoes was associated with improved tolerance to water stress.  相似文献   
2.
The objective of this study was to profile gene expression in cells of the chicken immune system. A low-density immune-specific microarray was constructed that contained genes with known functions in the chicken immune system, in addition to chicken-expressed sequence tags (ESTs) homologous with mammalian immune system genes, which were systematically characterized by bioinformatic analyses. Genes and ESTs that met the annotation criteria were amplified and placed on a microarray. The microarray contained 84 immune system gene elements. As a means of calibration, the microarray was then used to examine gene expression in chicken B cells after lipopolysaccharide stimulation. Differential gene expression was observed at 6, 12, and 24 h but not at 48 h after stimulation. The results were validated by semiquantitative polymerase chain reaction. The microarray showed a high degree of reproducibility, as demonstrated by intra- and interassay correlation coefficients of 0.97 and 0.95, respectively. Thus, the low-density microarray developed in this study may be used as a tool for monitoring gene expression in the chicken immune system.  相似文献   
3.
A lysimeter experiment was conducted to investigate the effect of water table management (WTM) on distribution of soil salinity and annual alfalfa (Medicago scutellata) yield. Subirrigations with three levels of water table namely, 0.5 (WT0.5), 0.7 (WT0.7), and 1.0 m (WT1.0) and a free drainage (FD) conventional irrigation treatment were selected for this study. All treatments were arranged in a complete randomized block design with three replicates. The results of this study indicated that the average soil electrical conductivity of the saturated extract (ECe) in the root zone gradually increased and exceeded the designated crop threshold value (4 dS/m) after the first forage harvest in subirrigated lysimeters. A higher salt accumulation was observed at the WT0.5 treatment. The average dry matter yield of annual alfalfa in WT0.5 and WT0.7 treatments was found to be 52 and 73% higher compared with the control treatment, respectively.  相似文献   
4.
The present study was carried out to characterize ACE inhibitory peptides which are released from the trypsin hydrolysate of wheat gluten protein. In silico proteolitic digestion of a high molecular weight glutenin subunit was performed. Among the resultant fragments, four peptides were selected for chemical synthesis based on the chemoinformatics studies and docking properties. The ACE inhibitory activity and kinetic parameters of the most important peptides were determined. Molecular docking simulation was also performed to predict the sites on ACE in which these peptides bind and displayed inhibition mechanisms. Two peptide sequences of IPALLKR (P4) and AQQLAAQLPAMCR (P6) showed higher ACE inhibitory activity among peptide collection. The IC50 values of P6 and P4 were 43 ± 1.3 μM and 68 ± 2.8 μM, respectively. P6 peptide was proved to be a more potent ACE inhibitor than P4 peptide. Lineweaver-Burk plots revealed that P6 and P4 behaved as non-competitive and competitive ACE inhibitors, respectively. The simulations showed that P4 bound to the active site region. Conversely, P6 bound to the N-terminus entrance of substrate tunnel and obstructed the substrate access into the catalytic site. Overall, the results showed that these peptides would be considered as a model for discovering new bio-compatible ACE inhibitors.  相似文献   
5.
Summary Seeds of early generations of three reciprocal congruity-backcross (CBC) pedigrees, developed by backcrossing Phaseolus vulgaris-P. acutifolius hybrids to each of the parent species in alternate generations, exhibited a preponderance of traits (size, shape, color, and pattern) of the cytoplasmic parent. The large size of Red Cloud (V1), the P. vulgaris parent common to all of the pedigrees, dominated pedigrees with V1 as the cytoplasmic parent, while the small size and rounded or square shapes of the tepary parents, wild P. acutifolius var. acutifolius PI 263590 or G400445 (A19), wild P. acutifolius var. latifolius PI 406622 (A10), or cultivated P. acutifolius var. latifolius Serowi PI 319443 (A9), were the majority phenotypes when P. acutifolius was the cytoplasmic parent. Continuing through the second cycle of CBC, that is the second backcross with each of the parent species or the fourth backcross, began an amelioration of the apparent cytoplasmic effect on gene expression, as reciprocal pedigrees became more alike, usually with intermediate expression of parental traits or the appearance of new traits. The large seed size of V1 was recovered in hybrids with P. acutifolius cytoplasm and the kidney shape of V1 became rare in hybrids with P. vulgaris cytoplasm. Although the tepary-bean parents represented two subspecies and both cultivated and wild P. acutifolius, the three sets of reciprocal-hybrid pedigrees with P. vulgaris Red Cloud are surprisingly similar. It may be that the exotic parent used to develop a CBC pedigree should be selected more for combining ability in the interspecific cross than for specific economic traits. While the number of generations (six or more) required to produce fertile, intermediate CBC hybrids (that did not require embryo rescue) may preclude routine use of this method by practical plant breeders, the crossability of advanced hybrids with both parental species and the amount of variability apparent in advanced-hybrids progenies suggests that CBC would be valuable for maintaining exotic germplasm in immediately useful forms.  相似文献   
6.
It has been hypothesized that the uptake of organic as opposed to inorganic nitrogen compounds found in wastewater can be properly substituted for plant nutrients. The objective of this study was to compare effects of applying monosodium glutamate wastewater (MGW) and ammonium nitrate (NH4NO3) (AN) on nitrogen metabolism and growth of lettuce. The results showed that while NH4NO3 (AN), NO3-, nitrite content and NR activity increased the protein content of lettuce. Applying MGW with a high concentration of 17 amino acids and macro- and microelements improved the fresh weights of shoot and root as well as the protein content of lettuce. Antioxidant activities were not affected by AN and MGW, and their interaction effects only increased POD after 8 weeks. In conclusion, substituting a portion of the chemical fertilizers with MGW improved lettuce growth, but did not increase NO3- accumulation in leaves.  相似文献   
7.
There is a need to produce a vaccine against Rhodococcus equi pneumonia in foals in which immunity against infection is largely based on a type 1, cell-mediated, immune response. The VapA protein of the virulence plasmid of R. equi is highly immunogenic. To assess the potential of vapA-DNA to produce immunity, C57BL/6 and BALB/c mice were immunized with a DNA vaccine constructed from vapA incorporated into pcDNA3.1. The plasmid construct expressed VapA in a COS-7 cell line. Intramuscular immunization of mice resulted in enhanced clearance of R. equi from the liver of intravenously challenged mice compared to non-immunized controls. This effect was more marked when pORF-IL-12, a plasmid expressing murine IL12, was included with the vaccine. Antibody developed to VapA, with an IgG2a response being more marked in mice immunized with pcDNA-vapA than in non-immunized or in mice immunized with the mixed vapA and IL-12 plasmid constructs. In conclusion, this study has shown for the first time that DNA immunization with vapA enhances the immune responses of mice against R. equi infection, that the IgG subisotype response is consistent with a type 1-based immune response, and that this can be enhanced by injection of the IL-12 gene.  相似文献   
8.
In Marek's disease virus infection, feather follicle epithelium (FFE) constitutes the site of formation of infectious virus particles and virus shedding. The objective of this study was to characterize cellular and cytokine responses as indicators of cell-mediated immune response in FFE and associated feather pulp following immunization against Marek's disease. Analysis of feather tips collected between 4 and 28 days post-immunization (d.p.i.) from chickens vaccinated post-hatch with either CVI988/Rispens or herpesvirus of turkeys revealed that replication of these vaccine viruses started at 7d.p.i., peaked by 21d.p.i., and subsequently, showed a declining trend. This pattern of viral replication, which led to viral genome accumulation in feather tips, was associated with infiltration of T cell subsets particularly CD8+ T cells into the feather pulp area and the expression of cytokine genes such as interferon-gamma, which is an indication of elicitation of cell-mediated immune responses at the site of virus shedding.  相似文献   
9.
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   
10.
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   
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