Effect of preharvest UV-C treatment of tomatoes (Solanum lycopersicon Mill.) on ripening and pathogen resistance     

Matthew A. ObandeGregory A. Tucker  Gilbert Shama 《Postharvest Biology and Technology》2011,62(2):188-192

Treatment with UV-C of tomato fruit on the vine was conducted using a mobile unit that was designed to be conveyed between the rows of tomato plants in a commercial glasshouse. Trusses of fruit both at the ripe and mature green phase were treated with UV-C doses of 3 and 8 kJ/m². Ripe fruit were picked 8 h after treatment and kept at room temperature for up to 16 d during which colour development and texture were monitored and compared to untreated controls. Mature green fruit treated on the vine with UV-C doses of 3 or 8 kJ/m² showed only a slight loss in green pigmentation in contrast to the tomato colour index (TCI) of control fruit which increased sharply 5 d after treatment. The TCI of ripe fruit treated with UV-C at a dose of 8 kJ/m² showed a lag of 10 d before increasing to a final value comparable to that of untreated fruit. Fruit treated with a dose of 3 kJ/m² did not display a lag but the increase in TCI occurred at a lower rate than for the controls. Firmness remained higher in fruit treated with the highest UV-C dose compared to fruit treated with the lower UV-C dose and controls. Fruit covered with UV impermeable film on the same plants as those that had received a UV-C dose of 3 kJ/m² had become ripe by day 6 in a manner similar to that of the controls. By contrast, fruit from trusses adjacent to those that had been treated with a UV-C dose of 8 kJ/m² remained green over the same period of time. Ripe fruit treated as described above were inoculated with spores of Penicillium digitatum after UV-C treatment and their firmness monitored over 12 d. A dose response effect was found with fruit treated at the highest dose remaining firmer than those treated at the lower dose and the controls.  相似文献   

Comment on "Protein sequences from mastodon and Tyrannosaurus rex revealed by mass spectrometry"     

Buckley M  Walker A  Ho SY  Yang Y  Smith C  Ashton P  Oates JT  Cappellini E  Koon H  Penkman K  Elsworth B  Ashford D  Solazzo C  Andrews P  Strahler J  Shapiro B  Ostrom P  Gandhi H  Miller W  Raney B  Zylber MI  Gilbert MT  Prigodich RV  Ryan M  Rijsdijk KF  Janoo A  Collins MJ 《Science (New York, N.Y.)》2008,319(5859):33; author reply 33

We used authentication tests developed for ancient DNA to evaluate claims by Asara et al. (Reports, 13 April 2007, p. 280) of collagen peptide sequences recovered from mastodon and Tyrannosaurus rex fossils. Although the mastodon samples pass these tests, absence of amino acid composition data, lack of evidence for peptide deamidation, and association of alpha1(I) collagen sequences with amphibians rather than birds suggest that T. rex does not.  相似文献   

Progress towards international targets for protected area coverage in mountains: A multi-scale assessment     

David Rodríguez-Rodríguez  Bastian Bomhard  Stuart H.M. Butchart  Matthew N. Foster 《Biological conservation》2011,144(12):2978-2983

Through the Convention on Biological Diversity (CBD), the world’s governments recently adopted a target to protect “at least 17% of terrestrial and inland water areas” by 2020. One of the CBD’s thematic programmes of work focuses on mountains, given their importance for biodiversity and other ecosystem services, and their vulnerability to global change. We evaluated current levels of protection for mountains at multiple scales. Encouragingly, the CBD’s 17% target has already been almost met at a global scale: 16.9% of the world’s mountain areas outside Antarctica fall within protected areas. However, protection of mountain areas at finer scales remains uneven and is largely insufficient, with 63% (125) of countries, 57% (4) of realms, 67% (8) of biomes, 61% (437) of ecoregions and 53% (100) of Global 200 priority ecoregions falling short of the target. The target also calls for protected areas to be focussed “especially [at] areas of particular importance for biodiversity”. Important Bird Areas and Alliance for Zero Extinction sites represent existing global networks of such sites. It is therefore of major concern that 39% and 45% respectively of these sites in mountain areas remain entirely unprotected. Achievement of the 2020 CBD target in mountain regions will require more focused expansion of the protected area network in addition to enhanced management of individual sites and the wider countryside in order to ensure long term conservation of montane biodiversity and the other ecosystem services it provides.  相似文献   

Long-term management impacts on carbon storage in Lake States forests   总被引：2，自引：0，他引：2  

Matthew Powers  Randall Kolka 《Forest Ecology and Management》2011,262(3):424-431

We examined carbon storage following 50+ years of forest management in two long-term silvicultural studies in red pine and northern hardwood ecosystems of North America’s Great Lakes region. The studies contrasted various thinning intensities (red pine) or selection cuttings, shelterwoods, and diameter-limit cuttings (northern hardwoods) to unmanaged controls of similar ages, providing a unique opportunity to evaluate long-term management impacts on carbon pools in two major North American forest types. Management resulted in total ecosystem carbon pools of 130-137 Mg ha⁻¹ in thinned red pine and 96-177 Mg ha⁻¹ in managed northern hardwoods compared to 195 Mg ha⁻¹ in unmanaged red pine and 224 Mg ha⁻¹ in unmanaged northern hardwoods. Managed stands had smaller tree and deadwood pools than unmanaged stands in both ecosystems, but management had limited impacts on understory, forest floor, and soil carbon pools. Total carbon storage and storage in individual pools varied little across thinning intensities in red pine. In northern hardwoods, selection cuttings stored more carbon than the diameter-limit treatment, and selection cuttings generally had larger tree carbon pools than the shelterwood or diameter-limit treatments. The proportion of total ecosystem carbon stored in mineral soil tended to increase with increasing treatment intensity in both ecosystems, while the proportion of total ecosystem carbon stored in the tree layer typically decreased with increasing treatment intensity. When carbon storage in harvested wood products was added to total ecosystem carbon, selection cuttings and unmanaged stands stored similar levels of carbon in northern hardwoods, but carbon storage in unmanaged stands was higher than that of thinned stands for red pine even after adding harvested wood product carbon to total ecosystem carbon. Our results indicate long-term management decreased on-site carbon storage in red pine and northern hardwood ecosystems, but thinning intensity had little impact on carbon storage in red pine while increasing management intensity greatly reduced carbon storage in northern hardwoods. These findings suggest thinning to produce different stand structures would have limited impacts on carbon storage in red pine, but selection cuttings likely offer the best carbon management options in northern hardwoods.  相似文献   

Forest productivity and tree diversity relationships depend on ecological context within mid-Atlantic and Appalachian forests (USA)   总被引：1，自引：0，他引：1  

R. Travis Belote  Steve PrisleyRobert H. Jones  Matthew FitzpatrickKirsten de Beurs 《Forest Ecology and Management》2011,261(7):1315-1324

Factors influencing the relationship between ecosystem productivity and biological diversity form the basis of much ecological theory. An understanding of how productivity-diversity relationships are influenced by scale of observation and unique attributes of ecoregions may provide important insights to aid conservation planning for carbon retention and biodiversity. Here we use publically available datasets to investigate patterns of productivity-diversity and explore potential factors influencing these patterns in forests located in five mid-Atlantic and Appalachian states. We used a geographic information system (GIS) to overlay multiple publically available datasets including remotely sensed estimates of productivity from MODIS and tree diversity estimated from the forest inventory analysis (FIA) database. We evaluated productivity-diversity relationships using two scales of observation (among and within ecoregions). We also determined if productivity-diversity relationships might be related to region-wide patterns in land use, and if the relationships varied by forest type, land management zones, and along gradients of mean productivity and diversity. Productivity-diversity relationships depended on scale and varied among ecoregions, and land use was correlated with both productivity and diversity. Mountainous ecoregions were characterized by positive productivity-diversity relationships, whereas coastal ecoregions were characterized by negative productivity-diversity relationships. Forest types and management zones that were on average less productive and more diverse exhibited positive productivity-diversity relationships across stands (the most productive stands were more diverse). In contrast, ecoregions and forest types that were on average more productive and less diverse exhibited negative productivity-diversity relationships (the most productive stands were less diverse). In conclusion, regional and local ecological and anthropogenic factors likely influence productivity-diversity relationships and these relationships appear to change along gradients of productivity and diversity.  相似文献   

Effects of Vegetation in Mitigating the Toxicity of Pesticide Mixtures in Sediments of a Wetland Mesocosm   总被引：1，自引：0，他引：1  

Richard E. Lizotte Jr.  Matthew T. Moore  Martin A. Locke  Robert Kr?ger 《Water, air, and soil pollution》2011,219(1-4):69-79

Conditions for tributyltin (TBT) solubilization and degradation were investigated. These conditions were optimized to remove or degrade organotin compounds (OTC) in spiked kaolin. TBT-spiked kaolin and reagents with specific chemical properties were tested in a batch reactor using a solid matrix model. The final concentrations of butyltin compounds in kaolin were determined by gas chromatography coupled with a pulsed flame photometric detector. Best results were obtained under acidic conditions (2?<?pH?<?5) with up to 87% TBT removal from the spiked kaolin. Acids with reducing properties were more effective (ascorbic and formic acid: 87% and 82% of TBT abatement, respectively). Moreover, final monobutyltin and dibutyltin concentrations were analyzed to determine which species predominate in the solid matrix after batch experiments. OTC speciation shows that degradation of TBT occurs simultaneously with solubilization in the presence of several reagents. These results allow choosing favorable/optimal operating conditions for OTC elimination.  相似文献   

Evaluation of compositional equivalence for multitrait biotechnology crops     

Ridley WP  Harrigan GG  Breeze ML  Nemeth MA  Sidhu RS  Glenn KC 《Journal of agricultural and food chemistry》2011,59(11):5865-5876

Compositional analysis is an important tool in the evaluation of the safety and nutritional status of biotechnology-derived crops. As part of the comparative assessment of a biotechnology-derived crop, its composition is evaluated by quantitative measurement of the levels of key nutrients, antinutrients, and secondary metabolites and compared to that of conventional crops. To evaluate the effect of combining multiple biotech traits through conventional breeding, the forage and grain compositions of the double combinations MON 810 × NK603, MON 863 × MON 810, and MON 863 × NK603 and the triple combination MON 863 × NK603 × MON 810 were compared to their respective near-isogenic, conventional control hybrids. Overall, a total of 241 statistical comparisons between the multitrait biotechnology crop and its corresponding conventional controls were conducted. Of these comparisons 192 (79.7%) were not statistically significantly different (p > 0.05), and all 49 of the differences were within the 99% tolerance interval for commercial hybrids grown in the same field or related field trials. These data on combined trait biotechnology-derived products demonstrated that the forage and grain were compositionally equivalent to their conventional comparators, indicating the absence of any influence of combining insect protection and herbicide tolerance traits by conventional breeding on compositional variation.  相似文献   

Assessing the impacts of international trade on CITES-listed species: Current practices and opportunities for scientific research     

Matthew J. Smith  Hesiquio Benítez-Díaz  Margarita África Clemente-Muñoz  John Donaldson  Jon M. Hutton  H. Noel McGough  Rodrigo A. Medellin  David H.W. Morgan  Colman O’Criodain  Thomasina E.E. Oldfield  Uwe Schippmann  Richard J. Williams 《Biological conservation》2011,(1):82-91

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) came into effect in 1975 to protect certain species of wild fauna and flora against over-exploitation through international trade. Determining which trade is detrimental to the survival of species in the wild can be a major difficulty in the implementation of CITES by national authorities, partly due to limited knowledge and understanding of the species’ biology, management, and the impacts of harvesting. Some of this knowledge could be acquired through targeted scientific research. However, to date there exists no general overview of the current use of biological information in determining detriment in CITES to help scientists identify research priorities. For an international meeting in 2008, over 100 scientists and regulators compiled 60 case studies covering a wide range of CITES-listed taxa, outlining how information on the biology, harvesting and management might be used to determine whether international trade is detrimental. We used these case studies, workshop conclusions, and other published literature, to identify 10 potential research directions for the scientific community which, if addressed, could greatly assist in the making of Non-Detriment Findings. We hope that this will encourage more scientists to study CITES-listed species, and foster more collaboration between research scientists, CITES national authorities, CITES technical committees and local communities. The case studies highlight a general need for advice on how to identify and manage levels of risk involved when assessing possible detriment, and for advice on assessing detriment under complex harvesting scenarios such as when multiple species, or parts of individuals, are harvested. Broadly, they highlight an opportunity for scientists to further develop a body of scientific studies that propose, refine and adapt methods for assessing detrimental trade in CITES-listed taxa. Comparisons within life-form groups indicated the potential for the identification of practical advice that could apply to groups of taxa. The case studies highlighted a widespread need for more information gathering studies of CITES-listed taxa such as the broader impacts of harvesting on populations and ecosystems, and the potential long-term evolutionary impacts. The case studies also highlighted the need for practical advice on how to implement adaptive management programmes and for research into enterprises based on the harvesting of CITES-listed species from the wild.  相似文献   

Joint Modeling of Spatial Variability and Within-Row Interplot Competition to Increase the Efficiency of Plant Improvement     

Joanne K. Stringer  Brian R. Cullis  Robin Thompson 《Journal of Agricultural, Biological & Environmental Statistics》2011,16(2):269-281

Trials in the early stages of selection are often subject to variation arising from spatial variability and interplot competition, which can seriously bias the assessment of varietal performance and reduce genetic progress. An approach to jointly model both sources of bias is presented. It models genotypic and residual competition and also global and extraneous spatial variation. Variety effects were considered random and residual maximum likelihood was used for parameter estimation. Competition at the residual level was examined using two special simultaneous autoregressive models. An equal-roots second-order autoregressive (EAR(2)) model is proposed for trials where competition is dominant. An equal-roots third-order autoregressive (EAR(3)) model allows for competition and spatial variability. These models are applied to two yield data sets from an Australian sugarcane selection program. One data set is in the paper and the other is in supplementary material available online. To determine the effect of simultaneously adjusting for spatial variability and interplot competition on selection, the percentages of superior varieties in common in the top 15% for the joint model and classical approaches were compared. Agreement between the two approaches was 45 and 84%. Hence, for some trials there are large differences in varieties advanced to the next stage of selection.  相似文献   

Species Occupancy Modeling for Detection Data Collected Along a Transect     

Gurutzeta Guillera-Arroita  Byron J. T. Morgan  Martin S. Ridout  Matthew Linkie 《Journal of Agricultural, Biological & Environmental Statistics》2011,16(3):301-317

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