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121.
Tran Ho Quang Nguyen Duc Kien Sara von Arnold Gunnar Jansson Ha Huy Thinh David Clapham 《New Forests》2010,39(3):301-312
Lignin and cellulose contents and wood basic density were related to diameter at breast height (DBH) in six fast-growing and
five slow-growing families from a combined progeny test and seedling seed orchard of Eucalyptus urophylla grown for 10 years in northern Vietnam. The mean cellulose content of the fast-growing families was significantly higher
than that of the slow growing-families (40.0 and 37.1%, respectively), and for individual trees cellulose content was significantly
correlated phenotypically with DBH. Wood basic density was significantly lower in the fast-growing group than in the slow-growing
group (0.506 and 0.535 g cm−3, respectively), and was significantly negatively correlated phenotypically with DBH. The lignin contents were not significantly
different between groups. Cellulose content and wood basic density were not correlated. The main conclusion is that there
is no obstacle to combining high growth rate with high cellulose content, for plantation of forests intended mainly for pulpwood. 相似文献
122.
Biodiversity is associated with indicators of soil ecosystem functions over a landscape gradient of agricultural intensification 总被引:1,自引:1,他引:0
Steven W. Culman Anna Young-Mathews Allan D. Hollander Howard Ferris Sara Sánchez-Moreno Anthony T. O’Geen Louise E. Jackson 《Landscape Ecology》2010,25(9):1333-1348
Agricultural intensification has led to dramatic losses in biodiversity over the past several decades. Many studies have shown
the effects of intensification on vegetation or soil communities at field or local scales. However, the functional significance
of biodiversity may only appear at larger spatial and temporal scales, due to exchanges among local ecosystems throughout
a landscape. To examine how patterns of biodiversity loss are reflected at larger spatial scales, plant and soil biodiversity
and associated indicators of ecosystem functions were assessed in riparian areas over a 150 km2 agricultural landscape in the Sacramento Valley of California. Publicly-available GIS data were first used to classify and
select sites over the range of soils, topography and plant community types. Representative sites from the landscape were sampled
for soil physiochemical properties, as well as microbial, nematode, and plant communities. Higher agricultural intensification,
based on field and landscape indices, was negatively correlated with richness and diversity of plant and soil taxa, and was
related to indicators of ecosystem functions, such as increased soil nitrate and phosphorus loading, decreased riparian health
ratings, and lower soil carbon, soil microbial biomass and soil food web structure. Both field- and landscape-scale factors
played important roles in the measured losses. The study area was composed of a wide array of soils, vegetation, and land
management, indicating that the observed trends transcended site-specific conditions. 相似文献
123.
Tito Caffi Sara Elisabetta Legler Riccardo Bugiani Vittorio Rossi 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(4):817-829
Chasmothecia of Erysiphe necator form in one season, survive winter and discharge ascospores that cause primary infections and trigger powdery mildew epidemics in the next season. A strategy for powdery mildew control was developed based on (i) the reduction in overwintering chasmothecia and on (ii) spring fungicide applications to control ascosporic infections timed based on estimate risk (two to five sprays per season). Several fungicides, the hyperparasite Ampelomyces quisqualis, and a mineral oil product were first tested as separate applications in a greenhouse and in vineyards. In the greenhouse, A. quisqualis suppressed chasmothecia formation by 41 %; fungicides and mineral oil suppressed chasmothecia formation by 63 % and ascospore viability by 71 %. In vineyards, application of boscalid + kresoxim-methyl or meptyldinocap once after harvest, as well as application of A. quisqualis pre- and post-harvest, delayed disease onset and epidemic development in the following season by 1 to 3 weeks and lowered disease severity (up to the pea-sized berry stage) by 56 to 63 %. Risk-based applications of sulphur and of synthetic fungicides provided the same control as the grower spray program but required fewer applications (average reduction of 47 %). Sanitation strategies were then tested by combining products and application times (late-season, and/or pre-bud break, and/or spring). Adequate disease control with a reduced number of sprays was achieved with the following combination: two applications of A. quisqualis (pre- and post-harvest), one application of mineral oil before bud break, and model-based applications of sulphur fungicides between bud break and fruit set. 相似文献
124.
Taste disturbances following consumption of pine nuts, referred to as "pine mouth", have been reported by consumers in the United States and Europe. Nuts of Pinus armandii have been associated with pine mouth, and a diagnostic index (DI) measuring the content of Δ5-unsaturated fatty acids relative to that of their fatty acid precursors has been proposed for identifying nuts from this species. A 100 m SLB-IL 111 GC column was used to improve fatty acid separations, and 45 pine nut samples were analyzed, including pine mouth-associated samples. This study examined the use of a DI for the identification of mixtures of pine nut species and showed the limitation of morphological characteristics for species identification. DI values for many commercial samples did not match those of known reference species, indicating that the majority of pine nuts collected in the U.S. market, including those associated with pine mouth, are mixtures of nuts from different Pinus species. 相似文献
125.
Cimmino A Andolfi A Fondevilla S Abouzeid MA Rubiales D Evidente A 《Journal of agricultural and food chemistry》2012,60(21):5273-5278
An aggressive isolate of Didymella pinodes isolated from pea ( Pisum sativum ) produced four different metabolites in vitro. The metabolites isolated from the culture filtrates were characterized by spectroscopic and optical methods. A new nonenolide, named pinolide, was isolated and characterized as (2S*,7R*,8S*,5E,9R*)-2,7,8-trihydroxy-9-propyl-5-nonen-9-olide. Pinolidoxin, the main toxin produced by D. pinodes, was also isolated together with two other closely related nonenolides, identified as herbarumin II and 2-epi-herbarumin II. Herbarumin II and 2-epi-herbarumin II have been previously isolated from the fungi Phoma herbarum and Paraphaeosphaeria recurvifoliae , respectively, but described here to be isolated for the first time from D. pinodes. When tested on leaves of the host plant and other legumes and weeds, pinolidoxin was phytotoxic in all of the plant species, whereas the other three nonenolides did not produce any symptoms. The importance of the stereochemistry of the hydroxy group at C-7 on phytotoxicity also is discussed. 相似文献
126.
Sara Hueso Gennaro Brunetti Nicola Senesi Karam Farrag Teresa Hernández Carlos García 《Journal of Soils and Sediments》2012,12(4):503-512
Purpose
The objective of this work was to assess the effect of severe drought conditions on the characteristics of semiarid soil humic acids (HAs) as well as the effect of organic amendment on such changes. 相似文献127.
Sara Sadat Aghabozorg Afjeh Behzad Boshehri Safar Hamednia Asmaolhosna Asmaolhosna Parisa Mashayekhi Mir Davood Omrani 《Iranian Biomedical Journal》2021,25(3):220
Background:Methadone therapy is a major protocol in opioid addiction cases in many health care systems. Population-based studies have shown that in addicted people, the genetic profile affects their response to methadone therapy. Therefore, this study designed to examine the frequency of two SNPs of the CYP2B6 gene (rs3745274 and rs3211371) in addicted cases in two methadone-responders and methadone non-responders groups. Methods:A total of 199 opioid-addicted individuals and 117 unaffected control subjects were genotyped for rs3745274 and rs3211371 polymorphisms of the CYP2B6 gene using the tetra-primer ARMS-PCR. Results:Results of this study revealed the significant association of rs3745274 GG (p < 0.001; OR = 0.027; 95% CI = 0.14-0.49) and GT (p < 0.001; OR = 4.04; 95% CI = 2.26-7.21) genotypes with the risk of addiction in methadone-responders. Also, a significant association between rs3745274 GG (p < 0.001; OR = 0.28; 95% CI = 0.15-0.51) and GT (p < 0.001; OR = 5.1; 95% CI = 2.8-5.28) genotypes and addiction relapse was found in methadone non-responders. Conclusion:Based on our findings, we can conclude that rs3745274 variant of CYP2B6 gene could serve as a potential biomarker, to evaluate the prognosis of addicted people fate under treatment with methadone. Key Words: Addiction, Biomarker, Methadone, Single-nucleotide polymorphism 相似文献
128.
Pandino G Lombardo S Mauromicale G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):291-297
The globe artichoke is a widely consumed vegetable in the Mediterranean Basin, with Italy being the leading producer. In southern
Italy, its cultivation contributes to local economic stability and social development. The producers are increasingly choosing
to replace autochthonous varieties, such as ‘Violetto di Sicilia’, with cultivars bred or selected outside of the region,
putting pressure on the maintenance of traditional varieties. Here, we have undertaken a detailed morphological and chemical
analysis of a group of clones selected from a population of ‘Violetto di Sicilia’. All the traits measured displayed genetic
variation, particularly the total content of phenolics and minerals. The capitula of the ‘Violetto di Sicilia’ clones contained,
on average, 6.3 g kg−1 of fresh weight total phenolics, compared with 4.5 g kg−1 in the two commercial varieties. The clones also had more inulin than commercial varieties (254 vs. 225 g kg−1 of dry matter), as well as a good mineral content. The set of clones is of interest in the context of the proposed improvement
of the crop through breeding and selection of genotypes with high nutritional quality and a specific end-use (industrial processing
or fresh consumption). 相似文献
129.
Physico‐chemical characterization of humic‐metal‐phosphate complexes and their potential application to the manufacture of new types of phosphate‐based fertilizers 下载免费PDF全文
Oscar Urrutia Javier Erro Inaki Guardado Sara San Francisco Marcos Mandado Roberto Baigorri Jean Claude Yvin José Ma Garcia‐Mina 《植物养料与土壤学杂志》2014,177(2):128-136
The aim of this review is to describe the main physicochemical characteristics of diverse types of humic‐metal‐phosphate acid complexes. The effects of these complexes on phosphorus (P) fixation in soils with different pH values and physicochemical features and on plant phosphorus uptake are also discussed. Humic‐metal‐phosphate complexes have apparent stability constants in the same range as those of metal‐humic complexes, in solutions with diverse pH and ionic‐strength values. Likewise, the molecular‐size distribution of humic‐metal‐phosphate complexes as a function of pH is similar to that of potassium or sodium humates and metal‐humic complexes. Humic‐metal‐phosphate complexes are able to decrease phosphate fixation in soils and increase plant growth and phosphate uptake. Phosphorus fertilizers containing humic‐metal‐phosphate complexes proved to be efficient to improve plant growth and P uptake with respect to conventional fertilizers such as single superphosphate. The values of parameters related to plant phosphorus‐utilization efficiency (PUt E) suggest that the regulation of root acquisition of phosphate from these complexes could involve the interregulation of a system for the optimization of metabolic P utilization in the shoot and another system involving stress responses of roots under phosphorus deficiency. 相似文献
130.