Institution
Agriculture and Agri-Food Canada
Facility•Ottawa, Ontario, Canada•
About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.
Topics: Population, Soil water, Manure, Tillage, Loam
Papers published on a yearly basis
Papers
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TL;DR: In this article, the authors proposed a minimum set of criteria for reliable soil N 2 O flux measurements using non-flow-through non-steady-state (NFT-NSS) chambers.
Abstract: The vast majority of soil N 2 O flux data reported in the literature was obtained using non-flow-through non-steady-state (NFT-NSS) chambers. Considerable variation in chamber methodology may influence N 2 O flux measurements, however, raising concerns about the reliability and accuracy of these measurements. The objectives of this study were to determine criteria for assessing the quality of soil N 2 O flux measurements made using NFT-NSS chambers, to evaluate NFT-NSS chamber methodologies used in the scientific literature, and to propose a minimum set of criteria for NFT-NSS chamber design and deployment methodology. We identified 16 characteristics of chamber methodology and developed four factors contributing to the quality of N 2 O flux measurements made using NFT-NSS chambers. We compiled a data set of 356 studies and evaluated the quality of each study against the set of characteristics and factors to determine the confidence in the reported N 2 O flux. Confidence in the absolute flux values reported in about 60% of the studies was estimated to be very low or low due to poor methodologies or incomplete reporting. The confidence in flux measurements improved with time; however, there were still about 50% of recent studies (2005-2007) with low or very low confidence levels. This study has shown that the quality of soil N 2 O flux measurements reported in the literature is often poor. While the flux data obtained may be valid for comparisons between situations (e.g., treatments) within a given study, they are often biased estimates of actual fluxes. We propose a minimum set of criteria for reliable soil N 2 O flux measurements using NFT-NSS chambers.
258 citations
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TL;DR: Bacteria in the mucosa were highly diverse but mainly Gram-positive with low G+C and Fusobacterium prausnitzii and butyrate-producing bacteria comprised the largest groups among 116 cloned sequences.
Abstract: We reported the first attempt to describe mucosa-associated bacterial populations in the chicken ceca by molecular analysis of 16S rRNA genes. Bacteria in the mucosa were highly diverse but mainly Gram-positive with low G+C. Fusobacterium prausnitzii and butyrate-producing bacteria comprised the largest groups among 116 cloned sequences. Twenty five percent of the clones had less than 95% homology to database sequences. Many sequences were related to those of uncultured bacteria identified in human feces or the bovine rumen. Terminal restriction fragment length polymorphism (T-RFLP) analysis revealed some differences between bacterial populations present in the mucosa and lumen of ceca. Greater resolution of bacterial population was obtained using a culture-independent approach rather than a culture-based approach.
258 citations
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TL;DR: Field spectral measurements collected over corn and wheat canopies in different intensive field campaigns organized during the growing seasons of 2004 and 2005 were used to test and evaluate several combined indices for chlorophyll determination using hyperspectral imagery (Compact Airborne Spectrographic Imager).
Abstract: This paper examines the use of simulated and measured canopy reflectance for chlorophyll estimation over crop canopies. Field spectral measurements were collected over corn and wheat canopies in different intensive field campaigns organized during the growing seasons of 2004 and 2005. They were used to test and evaluate several combined indices for chlorophyll determination using hyperspectral imagery (Compact Airborne Spectrographic Imager). Several index combinations were investigated using both PROSPECT-SAILH canopy simulated spectra and field-measured reflectances. The relationships between leaf chlorophyll content and combined optical indices have shown similar trends for both PROSPECT-SAILH simulated data and ground-measured data sets, which indicates that both spectral measurements and radiative transfer models hold comparable potential for the quantitative retrieval of crop foliar pigments. The data set used has shown that crop type had a clear influence on the establishment of predictive equations as well as on their validation. In addition to generating different predictive equations, corn and wheat data yielded contrasting agreement between estimated and measured chlorophyll contents even for the same predictive algorithm. Among the set of indices tested in this paper, index combinations like modified chlorophyll absorption ratio index/optimized soil-adjusted vegetation index (OSAVI), triangular chlorophyll index/OSAVI, moderate resolution imaging spectrometer terrestrial chlorophyll index/improved soil-adjusted vegetation index (MSAVI), and red-edge model/MSAVI seem to be relatively consistent and more stable as estimators of crop chlorophyll content.
258 citations
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TL;DR: The cloning and characterization of J are reported, and J is identified as the ortholog of Arabidopsis thaliana EARLY FLOWERING 3 (ELF3), and an important new component in flowering-time control in soybean is identified, providing new insight into soybean adaptation to tropical regions.
Abstract: Soybean is a major legume crop originating in temperate regions, and photoperiod responsiveness is a key factor in its latitudinal adaptation. Varieties from temperate regions introduced to lower latitudes mature early and have extremely low grain yields. Introduction of the long-juvenile (LJ) trait extends the vegetative phase and improves yield under short-day conditions, thereby enabling expansion of cultivation in tropical regions. Here we report the cloning and characterization of J, the major classical locus conferring the LJ trait, and identify J as the ortholog of Arabidopsis thaliana EARLY FLOWERING 3 (ELF3). J depends genetically on the legume-specific flowering repressor E1, and J protein physically associates with the E1 promoter to downregulate its transcription, relieving repression of two important FLOWERING LOCUS T (FT) genes and promoting flowering under short days. Our findings identify an important new component in flowering-time control in soybean and provide new insight into soybean adaptation to tropical regions.
257 citations
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TL;DR: In this paper, the authors tested for consistent relationships between landscape heterogeneity and biodiversity in farmland, with a view to developing simple rules for landscape management that could increase biodiversity within farmland, and found that mean crop field size had the strongest overall effect on biodiversity measures in crop fields, and this effect was consistently negative.
257 citations
Authors
Showing all 10964 results
Name | H-index | Papers | Citations |
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Fereidoon Shahidi | 119 | 951 | 57796 |
Miao Liu | 111 | 993 | 59811 |
Xiang Li | 97 | 1472 | 42301 |
Eviatar Nevo | 95 | 848 | 40066 |
Tim A. McAllister | 85 | 862 | 32409 |
Hubert Kolb | 84 | 420 | 25451 |
Daniel M. Weary | 83 | 437 | 22349 |
Karen A. Beauchemin | 83 | 423 | 22351 |
Nanthi Bolan | 83 | 550 | 31030 |
Oene Oenema | 80 | 361 | 23810 |
Santosh Kumar | 80 | 1196 | 29391 |
Yueming Jiang | 79 | 452 | 20563 |
Denis A. Angers | 76 | 256 | 19321 |
Tong Zhu | 72 | 472 | 18205 |
Christophe Lacroix | 69 | 353 | 15860 |