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Abstract

Wheat is the main source of carbohydrates and amino acids consumed in the world. Amino acids and other physiological characters were determined in six wheat genotypes viz. IBWSN-1010, IBWSN -1025, TD-1, ESW-9525, Khirman and Chakwal-86 for pot experiment, to evaluate the response of genotypes under water stress at Nuclear Institute of Agriculture (NIA), Tandojam, Sindh, Pakistan, during 2018. Eight different physiological indices (Proline content, glycine-betaine, total sugars, total chlorophyll, nitrate reductase activity (NRA), potassium (K+) content, osmotic potential (OP) and relative water content (RWC)) were determined. The variance of analysis shows two-way interaction one with water stress [Control (normal four irrigations) and the other with terminal drought (Soaking dose) having significance at p?≤?0.05. It was observed that, ESW9525, IBWSN-1010 and IBWSN-1025 exhibited the tolerance followed by, Khirman and Chakwal-86 by maintaining their OP and accumulation of higher proline and glycine-betaine content. Whereas, moderate total soluble sugars were found in these genotypes. However, NRA increased in IBWSN-1010 enhancing tolerance under water stress.  相似文献   
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Buried seeds that germinate during periods of low water or water level drawdown can play important roles in shaping plant community composition, community dynamics and species richness in ecosystems with fluctuating water levels. Northeastern US coastal plain ponds have fluctuating water levels and contain a characteristic shoreline flora that contains many rare plants. The objectives of this study were to: (1) test whether geographically distant ponds in Cape Cod and Martha’s Vineyard had distinct seed banks, (2) determine if hydrologic status as permanent and ephemeral ponds led to differences in seed banks, and (3) examine seed diversity and seed abundance across gradients of shoreline elevations and sediment characteristics. Viable seeds of 45 plant species were identified from nine ponds. Native species dominated pond-shore seed banks and made up 89-100% of all species. There was high overlap in seed bank composition across hydrological classes and geographic regions. One hydrological class captured 73-76% of total species and one geographical region captured 69-78% of the total species recovered from the entire suite of seed bank samples. Seeds were relatively evenly distributed along the shorelines of ephemeral ponds but seed diversity and abundance were lower at low elevations in permanent ponds. Results suggest that strategies to protect pond shorelines to capture maximum diversity of coastal plain pond plants contained in pond sediment seed banks should be implemented across pond hydrologic classes and across a wide geographic area. Shoreline seed distributions indicate that ground-water withdrawals or climate changes that lower pond water levels in permanent ponds will reduce the diversity and abundance of plants recovered from seed banks by shifting water levels to a shoreline zone of high sediment organic matter where seed densities are lower. This effect will be much less in ephemeral ponds where seed diversity and abundance on pond bottoms was high.  相似文献   
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Methanolic (VPME) and chloroformic (VPCL) extracts, obtained from the aerial parts of Vernonia polyanthes, were investigated for its antiulcerogenic properties. Administration of VPME (250 mg/kg) and VPCL (50 mg/kg) significantly inhibited the gastric mucosa damage (64% and 90%, respectively) caused by absolute ethanol (p.o.). Otherwise, in NSAID-induced gastric damage, their gastroprotective effects have decreased. Since the VPCL extract resulted to be more effective than the VPME we focused our efforts over VPCL action mechanism of action.  相似文献   
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Black saxaul (Haloxylon aphyllum) is a native tree species tolerant of aridity and salinity. It is planted to alleviate environmental damage due to the formation of the Aralkum desert and improve vegetation of the Aral Sea region. To investigate the environmental factors that determine seedling mortality and growth after rooting, we focused on soil properties and topographic factors in a study plot. We found that a hard clay layer that was low in hydraulic conductivity underlay accumulated sandy sediments at different depths. The soil in low seedling mortality areas was consistently sandy and low in salinity from the surface to a depth of 100 cm. In areas of high seedling mortality (75–100%), soils with a high content of silt and clay, with high salinity were detected within 100 cm depths. This suggests that accumulated sand sediment over a depth of 100 cm is required for root development. Plant height was positively correlated with depth of the hard clay layer. Significant relationships with plant height were also detected in chemical and physical properties at 80–100 cm such as electric conductivity (ECe), sodium adsorption ratio (SAR), and sand ratio. However, these properties had no significant relationship at 0–20 cm or with the relative elevation of the plot, suggesting that the subsequent growth of seedlings depends more on the sub-soil environment than on-surface conditions. The assessment of sub-soil condition is recommended to make site selection for reforestation much more reliable.  相似文献   
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Highland peatlands are one of the most fragile ecosystems in the world. These ecosystems have vital nutritional importance for livestock, however previous research has indicated that intensive grazing could negatively affect these communities, requiring the application of temporary grazing exclusion to restore the health of the peatland. The objective of our study was to evaluate the effect of grazing exclusion on plant allocation strategy and carrying capacity of Oxychloe andina Phil. The plant traits of O. andina were quantified through measurements of specific leaf area (SLA) and leaf dry matter content (LDMC). We estimated the carrying capacity through livestock censuses and vegetational transects. SLA was found to be greater in grazed conditions than in ungrazed conditions (p?=?0.0194) at five months after the application of treatments. Additionally, greater productivity associated with greater LDMC in March was observed under conditions of grazing exclusion (p?=?0.0306). Production estimates of O. andina reached 4816?kg of dry matter (DM) distributed over an area of 9.84?ha, which was equivalent to 489?kg DM of O. andina DM ha?1. Using DM production as a proxy of the peatland and considering the average vegetation cover of 70%, the peatland produces an estimated of 1370?kg DM year?1. The temporary grazing exclusion enhanced the productivity of O. andina. However, depending on DM production in relation to grazing demand, there is a possibility of exceeding the animal load for this plant species.  相似文献   
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The crude methanolic extract (ME) obtained from the leaves of Anacardium humile was evaluated orally at doses of 250-500-1000 mg/kg on gastric lesion on ethanol and piroxicam induced gastric lesions in rodents. All the tested doses significantly inhibited gastric lesions by 56 to 100%. These results seems to support the traditional use of this species in the treatment of gastric diseases.  相似文献   
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The aim of this study was to evaluate the effect of lyophilized bovine colostrum (LBC) used as partial source of dietary protein on the histological characteristics of the intestinal epithelium of juvenile dourado Salminus brasiliensis. Juveniles were fed diets containing 0%, 10% or 20% of LBC inclusion for either 30 or 60 days. For the histological study, the intestine was divided into three segments, S1, S2 and posterior intestine. In the S1 segment, interaction between treatment and period was observed in the number of goblet cells containing sialomucin, effect of treatment in the total number of goblet cells and effect of period in the number of goblet cells containing sulphomucins (P < 0.05). In the S2 segment, effect of period was observed in the number of goblet cells containing acid, neutral and total mucins, sialomucins and the partial volume of the absorptive mucosa (Vv) (P < 0.05). In the posterior intestine, effect of period was observed in the thickness of muscle layer and number of goblet cells containing sialomucins and sulphomucins (P < 0.05). Considering the aspects studied, the presence of 0%, 10% or 20% of LBC in the diet did not significantly influence the enteric histological characteristics of juvenile dourado during the period of the study.  相似文献   
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