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701.
Barley stripe rust caused by Puccinia striiformis f.sp. hordei (PSH) is one of the major diseases in barley production regions worldwide. A total of 336 barley genotypes with diverse genetic backgrounds targeted for low‐input barley production were tested for seedling and adult‐plant stage resistance against six PSH races (0S0, 0S0‐1, 1S0, 4S0, 5S0 and 7S0) originated from India. The seedling resistance was evaluated by inoculating the barley genotypes with six races separately under controlled conditions in Shimla, India. The same barley genotypes were evaluated for adult‐plant stage resistance in the Agricultural Research Station (ARS) of Rajasthan Agriculture University, Durgapura, Rajasthan, India. Out of the 336 barley genotypes tested for seedling resistance, 119 (35.4%), 101 (30.1%), 87 (25.9%), 100 (29.8%), 91 (27.1%) and 70 (20.8%) genotypes were resistant to races 0S0, 0S0‐1, 1S0, 4S0, 5S0 and 7S0, respectively. In the field, 102 (30.3%) genotypes showed the resistance response of which 18 (5.3%) genotypes were highly resistant to PSH. Barley genotypes AM‐14, AM‐177, AM‐37, AM‐120, AM‐300, AM‐36, AM‐103, AM‐189, AM‐291, AM‐275 and AM‐274 showed resistance response to all six races at seedling and adult‐plant stages. Seedling resistance reported in the current study is effective against the newly emerged race 7S0 and previously reported five races in India. Therefore, resistant barley genotypes identified in the current study provided effective protection against all six races at seedling and adult‐plant stages. The stripe rust resistance identified in the current studies may be potential donors of stripe rust resistance to barley breeding programmes in India and elsewhere.  相似文献   
702.
We have evaluated the ability of the injured nigrostriatal dopaminergic system to produce highly reactive hydroxyl radicals ((*)OH) by the electrochemical detection of salicylate hydroxylation. Unilateral transection of the medial forebrain bundle transiently increased the formation of (*)OH in substantia nigra (SN) but not in striatum during the first 48 h postlesion, when most relevant changes in terms of oxidatively modified proteins take place. Short-term adaptive axotomy-induced changes in substantia nigra included downregulation of nigral tyrosine hydroxylase (TH) and dopamine transporter (DAT) mRNA expression and more intense TH immunoreactivity. Maintained inhibition of monoamine oxidase activity with deprenyl totally prevented the axotomy-induced formation of (*)OH, thus demonstrating the dopaminergic nature of these radicals. In contrast, deprenyl treatment, which is associated with a diminution in free radical production, failed to delay the onset of dopaminergic degeneration. This observation highlights the importance of being extremely cautious when analyzing parameters of oxidative stress and extrapolating them as a primary cause of cell death in the context of neurodegeneration. Long-term adaptive changes included a dramatic downregulation of DAT mRNA expression along with a moderate decrease in TH mRNA levels in SN. We anticipate a key regulatory role of the DAT to maximally optimize dopaminergic transmission in the synaptic cleft under conditions of degeneration.  相似文献   
703.

BACKGROUND

Microbes affect the growth of plants. In this study, the diversity and plant growth-supporting activities of wheat rhizospheric bacteria were examined.

METHODS

Sampling was performed thrice at different phases of plant growth. Microbes associated with the rhizoplane of three wheat varieties (Seher, Lasani, and Faisalabad) were cultured and assessed for their plant growth-promoting abilities based on auxin production, hydrogen cyanide production, phosphate solubilization, and nitrogen fixation.

RESULTS

Bacterial load (CFU/mL) declined, and the succession of bacterial diversity occurred as the plants aged. Most auxin-producing bacteria and the highest concentrations of auxin (77 μg/mL) were observed during the second sampling point at the tillering stage. The Seher variety harbored the most auxin-producing as well as phosphate-solubilizing bacteria. Most of the bacteria belonged to Bacillus and Pseudomonas. Planomicrobium, Serratia, Rhizobium, Brevundimonas, Stenotrophomonas, and Exiguobacterium sp. were also found.

CONCLUSION

These results suggest that the rhizoplane microbiota associated with higher-yield plant varieties have better plant growth-promoting abilities as compared to the microbiota associated with lower-yield plant varieties.
  相似文献   
704.
This study, comprising three independent experiments, was conducted to optimize the zinc (Zn) application through seed coating for improving the productivity and grain biofortification of wheat. Experiment 1 was conducted in petri plates, while experiment 2 was conducted in sand-filled pots to optimize the Zn seed coating using two sources (ZnSO4, ZnCl2) of Zn. In the first two experiments, seeds of two wheat cultivars Lasani-2008 and Faisalabad-2008 were coated with 0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75 and 2.00 g Zn kg?1 seed using ZnSO4 and ZnCl2 as Zn sources. The results of experiment I revealed that seed coating with 1.25 and 1.50 g Zn kg?1 seed using both sources of Zn improved the seedling emergence. However, seed coated with 1.25 and 1.50 g Zn kg?1 seed using ZnSO4 was better regarding improvement in seedling growth and seedling dry weight. The results of the second experiment indicated that seed coated with 1.25 and 1.50 g Zn kg?1 seed using ZnSO4 improved the seedling emergence and seedling growth of tested wheat cultivars. However, seed coating beyond 1.5 g Zn kg?1 seed using either Zn source suppressed the seedling emergence. Third experiment was carried out in glass house in soil-filled earthen pots. Seeds of both wheat cultivars were coated with pre-optimized treatments (1.25, 1.50 g Zn kg?1 seed) using both Zn sources. Seed coating with all treatments of ZnSO4 and seed coating with 1.25 g Zn kg?1 seed using ZnCl2 improved the seedling emergence and yield-related traits of wheat cultivars. Seed coating with 1.25 g Zn kg?1 seed also improved the chlorophyll a and b contents. Maximum straw Zn contents, before and after anthesis, were recorded from seed coated with 1.5 g Zn kg?1 seed using either Zn source. Increase in grain yield from seed coating followed the sequence 1.25 g Zn kg?1 seed (ZnSO4) >1.25 g Zn kg?1 seed (ZnCl2) >1.5 g Zn kg?1 seed (ZnSO4). However, increase in grain Zn contents from seed coated was 1.5 g Zn kg?1 seed (ZnCl2) >1.25 and 1.5 g Zn kg?1 seed (ZnCl2, ZnSO4) >1.25 g Zn kg?1 seed (ZnSO4). Seed coating with Zn increased the grain Zn contents from 21 to 35 %, while 33–55 % improvement in grain yield was recorded. In conclusion, wheat seeds may be coated with 1.25 g Zn kg?1 seed using either source of Zn for improving the grain yield and grain Zn biofortification.  相似文献   
705.

Background

Medicinal flora plays a vital role in treating various types of ailments in living beings. The present study was planned to investigate and document systematically the indigenous knowledge in a scientifically little explored area of Ladha sub-division, South Waziristan agency, Pakistan. Hence, this study would contribute positively to the field of ethnopharmacology.

Methods

Prior to ethnomedicinal data collection, regular field visits were conducted during the month of May and June 2015 to locate the sites and respondents from where the traditional knowledge was to be recorded. Ethno-medicinal data was collected during the month July and August 2015 through rapid appraisal approach (RAA) based on direct interaction with the indigenous communities by making group discussions, corner meetings and semi-structured interviews. Data was evaluated statistically by using the index of Use value (UV) and Frequency of citations (FC).

Results

A total of 82 medicinal plants belonging to 42 families were reported in the study. Leaves were the most frequently used plant parts. Highest use values were recorded for Peganum harmala (0.93), Punica granatum (0.91), Thymus mongolicus (0.90), Chenopodium album (0.89), Coriandrum sativum (0.87), Mentha longifolia (0.87), Lactuca serriola (0.87) and Portulaca oleracea (0.87). Medicinal plants used for the gastro intestinal complexities and respiratory diseases were more than 9% followed by skin and diarrhea (7% each), liver disorders (5%) cough and cold fever (5%).

Conclusion

People of the area mostly still rely on traditional herbal therapies. Keeping in mind the dependence of the indigenous community for their primary health care on such herbal remedies, pharmacological and critical toxicological investigation of certain flora is necessary. Moreover, projects should be designed to analyze the existing issues and problems related with medicinal plants conservation.
  相似文献   
706.
In this study, we report on a group of complementary human osteoblast in vitro test methods for the preclinical evaluation of 3D porous titanium surfaces. The surfaces were prepared by additive manufacturing (electron beam melting [EBM]) and plasma spraying, allowing the creation of complex lattice surface geometries. Physical properties of the surfaces were characterized by SEM and profilometry and 3D in vitro cell culture using human osteoblasts. Primary human osteoblast cells were found to elicit greater differences between titanium sample surfaces than an MG63 osteoblast‐like cell line, particularly in terms of cell survival. Surface morphology was associated with higher osteoblast metabolic activity and mineralization on rougher titanium plasma spray coated surfaces than smoother surfaces. Differences in osteoblast survival and metabolic activity on titanium lattice structures were also found, despite analogous surface morphology at the cellular level. 3D confocal microscopy identified osteoblast organization within complex titanium surface geometries, adhesion, spreading, and alignment to the biomaterial strut geometries. Mineralized nodule formation throughout the lattice structures was also observed, and indicative of early markers of bone in‐growth on such materials. Testing methods such as those presented are not traditionally considered by medical device manufacturers, but we suggest have value as an increasingly vital tool in efficiently translating pre‐clinical studies, especially in balance with current regulatory practice, commercial demands, the 3Rs, and the relative merits of in vitro and in vivo studies. Biotechnol. Bioeng. 2016;113: 1586–1599. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.  相似文献   
707.
The aim of this study was to investigate the effects of a static magnetic field on six behavioral parameters (travel distance, average speed while in motion, travel distance of the head, body rotations, time in movement, and immobility time) of the ground beetle Laemostenus (Pristonychus) punctatus (Dejean) (Coleoptera: Carabidae). Adults of this troglophilic and guanophilic beetle were randomly divided into two groups, the first exposed to a static magnetic field of 110 mT for 5 h, and the second a control group. Beetle behavior after these 5 h was monitored in an open‐field test for 12 min and analyzed using ANY‐maze software. Exposure to a static magnetic field of 110 mT increased motor activity (travel distance and average speed while in motion) in the first 4 min. After that there were no significant differences. We conclude that the applied static magnetic field affects motor activity of adult specimens of L. (P.) punctatus, and we discuss the mechanism, possibly through acting on the control centers responsible for orientation and movement.  相似文献   
708.
709.
The phytochemical, antioxidant and mineral composition of hydroalcoholic extract of leaves of Cichorium intybus L., was determined. The leaves were found to possess comparatively higher values of total flavonoids, total phenolic acids. The phytochemical screening confirmed the presence of tannins, saponins, flavonoids, in the leaves of the plant. The leaf extract was found to show comparatively low value of IC50 for 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition. The IC50 value of chicory leaves extract was found to be 67.2 ± 2.6 μg/ml. The extracts were found to contain high amount of mineral elements especially Mg and Zn. Due to good phytochemical and antioxidant composition, C. intybus L., leaves would be an important candidate in pharmaceutical formulations and play an important role in improving the human health by participating in the antioxidant defense system against free radical generation.  相似文献   
710.
Among grain legumes, faba bean is becoming increasingly popular in European agriculture due to recent economic and environmental interests. Faba bean can be a highly productive crop, but it is sensitive to drought stress and yields can vary considerably from season to season. Understanding the physiological basis of drought tolerance would indicate traits that can be used as indirect selection criteria for the development of cultivars adapted to drought conditions. To assess genotypic variation in physiological traits associated with drought tolerance in faba bean and to determine relationships among these attributes, two pot experiments were established in a growth chamber using genetic materials that had previously been screened for drought response in the field. Nine inbred lines of diverse genetic backgrounds were tested under adequate water supply and limited water conditions. The genotypes showed substantial variation in shoot dry matter, water use, stomatal conductance, leaf temperature, transpiration efficiency, carbon isotope discrimination (Δ13C), relative water content (RWC) and osmotic potential, determined at pre-flowering vegetative stage. Moisture deficits decreased water usage and consequently shoot dry matter production. RWC, osmotic potential, stomatal conductance and Δ13C were lower, whereas leaf temperature and transpiration efficiency were higher in stressed plants, probably due to restricted transpirational cooling induced by stomatal closure. Furthermore, differences in stomatal conductance, leaf temperature, Δ13C and transpiration efficiency characterized genotypes that were physiologically more adapted to water deficit conditions. Correlation analysis also showed relatively strong relationships among these variables under well watered conditions. The drought tolerant genotypes, ILB-938/2 and Melodie showed lower stomatal conductance associated with warmer leaves, whereas higher stomatal conductance and cooler leaves were observed in sensitive lines (332/2/91/015/1 and Aurora/1). The lower value of Δ13C coupled with higher transpiration efficiency in ILB-938/2, relative to sensitive lines (Aurora/1 and Condor/3), is indeed a desirable characteristic for water-limited environments. Finally, the results showed that stomatal conductance, leaf temperature and Δ13C are promising physiological indicators for drought tolerance in faba bean. These variables could be measured in pot-grown plants at adequate water supply and may serve as indirect selection criteria to pre-screen genotypes.  相似文献   
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