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1.
Landscape Ecology - Several case studies investigated the role of ecosystem services in participatory planning processes. However, no systematic study exists that cuts across a large number of...  相似文献   
2.
1. This study was conducted to examine some egg characteristics and determine the effects of eggshell thickness and eggshell porosity on water loss and hatchability of eggs in ostriches. 2. Shell thickness did not correlate significantly with hatchability. However, eggs of low shell thickness lost more mass (13.03%) than those with intermediate (11.22%) and high (10.36%) shell thickness. Mass loss during incubation was higher in hatched (11.98%) than unhatched eggs (11.09%). Shell thickness was negatively correlated to egg mass loss (r = -0.65). 3. The pore density was correlated with hatchability. Hatchability was 50% lower in eggs with low pore densities (40.93%) than with high densities (80.94%). Pore density was positively correlated with egg mass loss (r = 0.63). Incubation mass losses of hatched and unhatched eggs were not significantly different. 4. Mean eggshell water vapour conductance (G) value and shell conductance constant (k) were 87.77 +/- 4.21 mg H2O/d/Torr and 2.44 respectively (n = 15). 5. Because of eggshell functional properties and resulting low egg mass loss hatchability is low when ostrich eggs are artificially incubated. The mass of eggs used in the experiment was relatively high and their eggshell water vapour conductance was low. As a result, egg incubation mass loss was lower than it should be. It is concluded that incubator humidity should be low (25%) to allow enough mass loss during incubation from the eggs.  相似文献   
3.
Artemisia annua L. is an aromatic-antibacterial herb that destroys malarial parasites, lowers fevers and checks bleeding, and of which the secondary compound of interest is artemisinin. The objective of the present study was to determine yield, yield components and artemisinin content of A. annua L. grown under four nitrogen applications (0, 40, 80 and 120 kg ha−1) in the Çukurova region of Turkey in 2004 and 2005. Field trials were conducted at Çukurova University, Agricultural Faculty Field Crops Department. In the study, plant height, number of branches, fresh herbage yield, dry herbage yield, fresh leaf yield, dry leaf yield, essential oil content and artemisinin content (by high performance liquid chromatography, HPLC) were examined. By analysis of variance, nitrogen doses had no any statistical effect on the traits investigated except for artemisinin content. Artemisinin content of the dried leaves were significantly affected by nitrogen applications, which varied from 6.32 to 27.50 mg 100 g−1. Contents were from 120 and 80 kg ha−1 nitrogen for the years of 2004 and 2005, respectively.  相似文献   
4.
Antibacterial activity of seed proteins of Robinia pseudoacacia   总被引:1,自引:0,他引:1  
A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.  相似文献   
5.
Sissoo (Dalbergia sissoo), commonly known as shisham, is amongst the finest woods of South Asia, but ‘wilt’ disease has caused a rapid decline in this species. The cause of the disease remains uncertain. The aim of this study is to identify the causal agent of the disease and characterize isolates made from diseased trees, based on genomic data and variations in virulence. Samples of infected roots, stems and the ooze exuded from infected trees were obtained from plants showing symptoms in different geographical regions of India for the isolation of microorganisms. Isolates were used to inoculate healthy plants. Based on the morphological characteristics, genus‐ and species‐specific PCR, and in silico analysis of 5.8S rDNA‐ITS regions, of the 38 fungal isolates, 24 and 14 were identified as Fusarium solani and Fusarium sp., respectively. In a pathotyping study, eighteen F. solani isolates, isolated from roots and stem parts of symptomatic plants, induced typical wilt symptoms when inoculated through soil and roots on D. sissoo seedlings of 1–15 months in age. The population of F. solani was the highest in infected roots and the lowest in parts of stems, gradually decreasing with height, and was isolated constantly up to approximately 40% height of the seedling. F. solani isolates used in inoculations were successfully re‐isolated from the rhizosphere, infected roots and wilted stems, as confirmed using isolate‐specific DNA fingerprints. Molecular phylogenies based on rDNA‐ITS sequences showed that the 38 isolates fell into 2 groups. Group I comprised of F. solani isolates from D. sissoo and F. solani sequences in the NCBI GenBank database, whereas group II included Fusarium isolates other than F. solani. These results are helpful in developing integrated control measures for this highly variable pathogen and to establish a base for future population studies.  相似文献   
6.
The objective of this study was to investigate the effect of storage temperatures and time on discoloration and oxidation of prepared chicken breast with paprika oleoresin. Freshly prepared chicken breast containing paprika oleoresin was stored at ?2, ?10, ?18°C, and an oscillating temperature between ?10 and ?18°C (?10/?18°C). A significant decrease in redness was detected at ?2, ?10, and ?10/?18°C. The lowest TBARS values and carbonyl contents were observed in the samples stored at ?18°C for 5 weeks. Also, the values of sulfhydryl groups gradually decreased with the increase in storage temperatures and duration. The results suggest a positive correlation between the loss of redness and oxidation in all samples. The findings indicated that the discoloration and oxidation of prepared chicken breast added with paprika oleoresin were inhibited significantly when stored at ?18°C.  相似文献   
7.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. granatum accessions was performed using three molecular markers, i.e., sequence related amplified polymorphism (SRAP), target region amplification polymorphism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40~870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (~90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.  相似文献   
8.
To reduce reliance on scientific fertilizer due to rapid increase of fertilizer prices and environmental constraint, it necessary to improve crop productivity and soil fertility on sustainable basses. Utilization of “summer gap” through biochar and legumes have pleasant effects on improving crop productivity and soil fertility on long term basses. Two years’ field experiments were conducted on wheat and maize crops with “summer gap” utilization with legumes and biochar at research farm of agronomy, the University of Agriculture Peshawar during 2011–2013. Wheat-maize-wheat cropping system was followed with the adjustment of legumes in “summer gap” (land available after wheat harvest till maize sowing). Legumes i.?e. mung bean, cowpea and Sesbania with a fallow were adjusted in the “summer gap” with and without biochar application. Biochar was included at the rate of 0 and 50?t?ha-1 with four N levels of 0, 90, 120, 150 and 0, 60, 90, 120?kg?ha-1 to subsequent maize and wheat crops, respectively. In legumes’ experiment, biochar increased fresh and dry fodder yield in cowpea and Sesbania, grain and biological yields in mung bean. In maize experiments, biochar improved grain yield. Nitrogen application increased grain and biological yields. In wheat experiments with increasing nitrogen level enhanced biological and grain yields. It is concluded that use of biochar and legumes in “summer gap” improve overall farm productivity and soil fertility on sustainable basses.  相似文献   
9.
Switchgrass (Panicum virgatum L.) is a promising bioenergy crop for temperate regions. Overwintering has been used to improve biomass quality, resulting in a more efficient combustion, partially due to a reduction in minerals concentration. This study examines the effects of soil composition on overwintered switchgrass composition. Samples were collected in the spring from 58 environments in Southern Quebec to determine possible relationships between soil composition and biomass quality. Principal component analysis and stepwise regressions were used to identify relationships between soil and biomass compositions. Soil parameters monitored explained 74% of the variation in biomass silicon (Si) concentration, 45% of the variation in ash, and 32% of the variation in magnesium (Mg). Soil composition had limited effects on the concentration of other elements in switchgrass biomass. Switchgrass biomass quality is influenced by soil composition and appears well suited to biomass combustion when overwintered and harvested in the spring.  相似文献   
10.
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