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71.
Topography is the most factor that has the greatest impact of all factor that affect the distribution.To study the diversity of trees and shrub species in the Perc forest situated in Khorramabad,Lorestan,140 circular plots of 1200 m~2 in a grid of 300 m 9 250 m were surveyed,using a systematic random sampling method.In each plot,the Margalef richness index,Shannon–Wiener diversity index,Hill's N_1 and Simpson indices and the evenness index of Simpson and Smith-Wilson were calculated and ordered on the basis of different classes of elevation,exposition and slope.The results indicated that slope did not have any significant effect on the indices.Exposition and elevation classes significant impacted the richness and diversity indices,but did not influence evenness.In general,the highest plant diversity was observed for slopes less than 15 %,northern aspects,without geographical direction,and elevations of 2100–2200 m.This information can be very useful in achieving the goals for sustainable management of forests.In addition to greater protection for regions with high diversity and reforestation(compatible species) in degraded area,we can help increase diversity in forests.  相似文献   
72.
Bitter pit in apples still causes significant losses, especially in the export markets of ‘Golden Delicious’ apples from South Africa. Orchard practices to reduce the possibility of bitter pit are followed, as well as destructive methods to predict the probability thereof, but the occurrence of bitter pit is still unacceptably high. Fluorescence imaging is a fast, non-destructive technique, able to evaluate numerous fruit within a short time span. By applying fluorescence imaging on individual fruit before any symptoms of bitter pit were apparent, lower fluorescence was shown to be associated with bitter pit development in apples in selective cases. Our results showed that, using averaged cumulative distribution functions (CDFs) of pitted and non-pitted fruit classes, it was possible to show a difference between these classes with fluorescence imaging. However, the individual distinction between all pitted and non-pitted fruit of our total sample, could not been defined as clearly.

In the majority of cases, on a single fruit basis, separation in groups was not satisfactory (less than 100% accurate) based on industry requirements for a prediction technique. Results of pre-harvest imaging on apples to identify fruit with bitter pit potential at harvest showed that pitted fruit were correctly classified (75–100%). However, misclassification of non-pitted fruit (50% and less) with fluorescence imaging is still too high to be of any commercial use.  相似文献   

73.
Anti-Müllerian hormone (AMH), produced by granulosa cells, has been reported to be elevated in mares with granulosa cell tumor. A 13-year-old Arabian mare was referred after 3 years of infertility. Rectal and ultrasonographic examination revealed enlargement and multicystic appearance of the left ovary. The mare had substantially higher concentration of AMH (21.6 ng/mL) compared with normal cyclic mares (n = 5; 0.36 ± 0.02 ng/mL). Testosterone (50 pg/mL) concentration was also elevated, but progesterone concentration (0.4 ng/mL) was lowered. Accordingly, the mare was presumptively diagnosed with granulosa-theca cell tumor and a left ovariectomy implemented using ventral midline approach under general anesthesia. Histopathological examination confirmed the diagnosis of granulosa-theca cell tumor. Serum concentrations of AMH decreased to 2 ng/mL and 0.5 ng/mL 2 and 4 weeks after tumor removal, respectively. In conclusion, the current report presents confirmatory evidence that evaluation of serum AMH could be useful for diagnosis of granulosa cell tumor in mare.  相似文献   
74.
Journal of Plant Diseases and Protection - Grapevine Pinot gris virus (GPGV) was firstly identified in northern Italy by deep sequencing from grapevine cv. Pinot gris, exhibiting mottling and...  相似文献   
75.
For developing nature-based silvicultural practices in a beech forest to promote, abundance, height,vitality, and preferred growth form, regenerated trees growing in gaps were compared with those under closed canopies.A systematic 50×50 m grid was plotted in a beech stand in the Kheyrud Experimental Forest for selecting trees to measure variables in gaps and under closed canopies.Abundance and mean height of regenerated beech trees were significantly higher in closed canopies than in canopy gaps.Beech seedlings with excurrent growth were significantly taller within regeneration patches under closed canopy.Moreover, regenerated trees with high vitality were more abundant in closed canopy areas than in gaps.Thus, beech regeneration should improve under closed canopies; hence, gaps in a near natural forest should be created only after adequate regeneration and appropriate growth under the parent tree in a closed canopy area is ensured.The results of this research have profound implications for the sustainable management of the forest and for ensuring sustainable beech regeneration.The presence of a closed canopy cover likely will reduce potential stresses on oriental beech regeneration.  相似文献   
76.
In this research, impact of climate change on wheat yield was simulated using SWAP in Myandoab, Iran. Field data of wheat in 2004–2005 and 2005–2006 periods were used for calibration and validation of the SWAP, respectively. The HadCM3 outputs, for A1B, A2 and B1 scenarios and 2046–2065 periods, were used in SWAP and wheat yield in mentioned period was compared with base period. Three irrigation levels, based on meeting 100, 70 and 50% of the crop ET demand, were used to study the climate change effects on wheat yield in full and deficit irrigation conditions. The results showed that temperature and reference evapotranspiration will increase in 2055s. Temperature increase cause to decrease crop growing period and crop evapotranspiration. The results showed that the negative impact of temperature increase has dominated to the positive impact of CO2 concentration and the yield is reduced. For full irrigation situation, the reduction will be 24.1, 22.4 and 20.8% in A1B, A2 and B1, respectively. Reduction in yield can be related to the shorter maturity period of the crop. The results showed that under deficit irrigation, the yield is also decreased but this decrease rate of yield is higher in full irrigation.  相似文献   
77.
Livestock grazing is a major driver of ecosystem functions in drylands and would be expected to influence soil biota such as termites. We examined changes in soil chemistry and plant community composition on mounds constructed by the subterranean termite Anacanthotermes ahngerianus along a gradient in grazing intensity in an arid steppe in north-eastern Iran. The grazing gradient was represented by increasing distance from an area used by resting livestock, and plant and soil attributes measured within three adjacent microsites (termite mounds, non-mound controls, intervening annular zone surrounding the mounds). Values of soil EC; pH; exchangeable Ca, Mg, and Na; and total nitrogen and organic carbon were greatest in mound soils and declined from mounds to control microsites. Mounds were completely devoid of plants. Annular zones had three-times less cover than the control sites, but there were no differences in diversity or evenness. Electrical conductivity values were ten-times greater on mounds than controls close to resting sites, but the difference diminished rapidly with distance from resting sites. For all other soil and plant variables, differences between microsites were consistent across the grazing gradient. Increased grazing intensity was associated with increasing soil pH, EC and sand content, and reduced plant cover. Overall our study shows that the effects of termites on soil chemistry and plant cover varied little across the grazing gradient. Our results suggest that termite mounds may sustain their role as sites of enhanced soil nutrients under even high levels of grazing.  相似文献   
78.
To determine the effect of water deficit on growth characteristics of 27 cotton cultivars (Gossypiumhirsutum L.), two separate experiments were performed in laboratory and glasshouse in Fars Province, Zarin-Dasht city (28° 36′ N, 54° 41′ E) in August 2015. In both experiments, which last for 10 days, a completely randomized block design with three replications was used. The main factor was water-deficit levels ((0, ?4, and ?12 MPa in laboratory and (0 and ?8 MPa) in glasshouse experiments), and the subsidiary factor was different cotton cultivars. The sensitivity to water deficit was compared based on factors such as germination rate, shoot and root lengths, fresh and dry weights, seed energy, and seed vigor. The results of both experiments indicated that Oltan, Opal, Pak, Armaghan, Super-Elit Golestan, Super-Elit Bakhteghan, SB-35, Super-Elit Arian, Khandagh, Tabela-18, and Sahel cultivars are more resistant and therefore are suitable candidates to increase plant density and uniformity in the farm.  相似文献   
79.
Oxytocin neurons have a physiological role in food intake and energy balance. Several studies have shown that central histaminergic and adrenergic systems synapse on oxytocin neurons but there is no information for their interaction on food intake regulation in birds. The purpose of this study was to examine the effects of intracerebroventricular (ICV) injection of α-fluoromethylhistidine (α-FMH, histidine decarboxylase inhibitor), chlorpheniramine (histamine H1 receptors antagonist), famotidine (histamine H2 receptors antagonist), thioperamide (histamine H3 receptors antagonist), prazosin (α1 receptor antagonist), yohimbine (α2 receptor antagonist), metoprolol (β1 adrenergic receptor antagonist), ICI 118,551 (β2 adrenergic receptor antagonist) and SR59230R (β3 adrenergic receptor antagonist) on oxytocin-induced hypophagia in 3-h food-deprived (FD3) neonatal broiler chicken. In Experiment 1, 3 h-fasted chicks were given an ICV injection of saline, α-FMH (250 nmol), oxytocin (10 μg) and co-injection of α-FMH + oxytocin. Experiments 2–9 were similar to experiment 1 except birds were injected with chlorpheniramine (300 nmol), famotidine (82 nmol), thioperamide (300 nmol), prazosin (10 nmol), yohimbine (13 nmol), metoprolol (24 nmol), ICI 118,551(5 nmol) and SR59230R (20 nmol) instead of α-FMH, respectively. After injection cumulative food intake was measured until 120 min post injection. According to the results, ICV injection of oxytocin significantly decreased food intake in broiler chickens (P < 0.001). ICV injection of α-FMH significantly attenuated hypophagic effect of oxytocin (P < 0.001). Also, co-injection of chlorpheniramine plus oxytocin significantly decreased the effect of oxytocin on food intake (P < 0.001). Co-administration of thioperamide and oxytocin significantly amplified hypophagic effect of oxytocin in chickens (P < 0.001). In addition, ICI 118,551 attenuated hypophagic effect of oxytocin (P < 0.001); while famotidine, prazosin, yohimbine, metoprolol and SR59230R had no effect on oxytocin- induced food intake in FD3 broiler chickens. These results suggest that the effect of oxytocin on food intake is probably mediated by histaminergic (via H1 and H3 receptors) and noradrenergic (via β2 receptors) systems in broiler chickens.  相似文献   
80.
Respiratory diseases in calves are responsible for major economic losses in both beef and dairy production. Several viruses, such as bovine respiratory syncytial virus (BRSV), bovine herpes virus-1 (BoHV-1), bovine parainfluenza virus-3 (BPI-3V), bovine viral diarrhea virus (BVDV), and bovine adenoviruses (BAV), are detected in most clinical cases with respiratory signs. The aim of this study is to define seroprevalences of five major viral causes of bovine respiratory infections in cattle in central region of Iran (Esfahan province). The population targeted was 642 dairy cows (Holstein–Friesian) from 25 farms. Samples of blood serum from female cattle were examined. Sera were tested by commercial ELISA kits to detect antibody against BRSV, BoHV-1, BPI-3V, BVDV, and BAV-3. The results were analyzed by Chi-square test. In the present study, seroprevalences of BRSV, BoHV-1, PI3V, BVDV, and BAV-3 were 51.1%, 72%, 84.4%, 49.2%, and 55.6%, respectively. The present study shows that infections of bovine respiratory viruses are very common in cattle in Esfahan.  相似文献   
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