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151.
Soil N mineralization is affected by microbial biomass and respiration, which are limited by available C and N. To examine
the relationship between C and N for soil microbial dynamics and N dynamics, we conducted long-term laboratory incubation
(150 days) after C and N amendment and measured changes in C and N mineralization, microbial biomass C, and dissolved C and
N throughout the incubation period. The study soil was volcanic immature soil from the southern part of Japan, which contains
lower C and N compared with other Japanese forest soils. Despite this, the area is covered by well-developed natural and plantation
forests. Carbon amendment resulted in an increase in both microbial biomass and respiration, and net N mineralization decreased,
probably due to increasing microbial immobilization. In contrast, N amendment resulted in a decrease in microbial respiration
and an increase in net N mineralization, possibly due to decreased immobilization by microbes. Amendment of both C and N simultaneously
did not affect microbial biomass and respiration, although net N mineralization was slightly increased. The results suggested
that inhibitory effect on microbial respiration by N amendment should be reduced if carbon availability is higher. Thus, soil
available C may limit microbial biomass and respiration in this volcanic immature soil. Even in immature soil where C and
N substrate is low, soil C, such as plant root exudates and materials from above- and belowground dead organisms, might help
to maintain microbial activity and N mineralization in this study site. 相似文献
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156.
ZiMin Hu FuLi Liu ZhanRu Shao JianTing Yao DeLin Duan 《Genetic Resources and Crop Evolution》2010,57(5):791-799
Unraveling the cryptic genetic diversity and selective breeding network in various Porphyra strains is of significance for conservation and utilization of economically important nori crops, for both current and future
needs. Here, we used nuclear ribosomal spacer (ITS1) region to investigate the genetic variation and intra-specific relatedness
of 59 Porphyra yezoensis Ueda specimens worldwide using phylogenetic and parsimony genealogical approaches. 23 nrDNA ITS1 genotypes were revealed
and clustering analysis grouped them into two distinct clades. High genetic diversity was detected in wild P. yezoensis strains from Miyagi and Hokkaido Prefectures in Japan, while the cultivated strains from China and South Korea exhibited
relatively higher genetic diversity likewise, which provided crucial genetic insights for future commercial breeding of P. yezoensis on a global scale. In addition, phylogenetic study has revealed the genetic relationship of strains with unknown parentage
to those with known parentage, and also ITS1 sequence pattern could be correlated with the geographic origin of P. yezoensis specimens. All these pedigree information generated from this research can be used to select parents for inter-specific or
intra-specific selective breeding and cross breeding to maximize the preservation of stock resource and sustainable development
of nori industry. 相似文献
157.
Xiaoliang Xiang Shuju Ning Xia Jiang Xiaogui Gong Renlei Zhu Lanfang Zhu Daozhi Wei 《Frontiers of Agriculture in China》2010,4(4):416-421
An efficient protein extraction method for two-dimensional gel electrophoresis (2-DE) from plant samples is usually challenging
due to the low protein content and high level of interfering compounds. Proteomic analyses of rice (Oryza sativa L.) roots are limited by the lack of an efficient protein extraction method. To establish an effective protocol of protein
extraction suitable for 2-DE analysis in rice roots, we evaluated three protein extraction methods (trichloroacetic acid [TCA]/acetone,
Mg/NP-40/TCA, and tris-base/acetone). Our results showed that the Mg/NP-40/TCA extraction method had the highest protein yield
and is the best resolution of protein separation among the three methods. The TCA/acetone method exhibited clear protein profiles
and detected more protein spots with the highest intensity in the region of high Mr (above 45 kDa) than the other methods.
However, this method was unable to detect proteins with low-Mr (less than 24.0 kDa). The Tris-base/acetone method showed the
poorest resolution of protein separation. Our results suggest that the Mg/NP-40/TCA method was the most effective among the
three methods and may provide enhanced proteomic information for rice and other crop roots. 相似文献
158.
Xueming Yang Jun Ma Haobing Li Hongxiang Ma Jinbao Yao Chunji Liu 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(4):495-502
Crown rot, caused by several Fusarium species, is one of the most damaging diseases in wheat and barley. Growing resistant varieties has long been recognised as
an integral part in effectively managing the disease. One of the factors hindering the progress of breeding for crown rot
resistance is the lack of a reliable and high throughput bioassay that allows rapid and accurate assessment of large numbers
of genotypes so that highly susceptible materials can be quickly rejected and potentially resistant lines identified for more
focused further assessments. We developed a method which, by growing several inoculated seedlings wrapped in a single piece
of moist paper towel, offers significant advantages over all of the existing methods. The new soil-less assay takes only about
two weeks, requires very little space, and removes variability associated with the use of soil/potting mixes. Results from
the new assay are highly reproducible and agree well with known field performances of different varieties. However, mapping
studies conducted using the new soil-less assay did not detect all of the quantitative trait loci found with a soil-based
assay. These results show that, although different resistance genes may all contribute to the performance of a variety, caution
should be used when comparing results from different assays. 相似文献
159.
160.
Genome-wide search for segregation distortion loci associated with the expression of complex traits in Populus tomentosa 总被引:1,自引:0,他引:1
Segregation distortion of molecular markers has been reported in a broad range of organisms. It has been detected in an interspecific BC1 Populus pedigree established by controlled crossing between clone “LM50” (Populus tomentosa) and its hybrid clone “TB01” (P. tomentosa×P. bolleana). The study with a total of 150 AFLP markers (approximately 18.9% of the total loci) exhibited significant deviation from the Mendelian ratio (1:1) (p<0.01). Twenty-five percent of the markers were mapped on the pa-rental specific genetic linkage maps of clones “LM50” and “TB01” with a pseudo-test-cross mapping strategy. Twelve linkage groups had markers with skewed segregation ratios, but the major regions were on linkage groups TLG2, TLG4 and TLG6 in the linkage map of clone “LM50”. We also analyzed the association between distorted loci and expression of complex traits with Map-maker/QTL software. A total of 16 putative QTLs affecting 12 traits were identified in the distorted regions on seven linkage groups. Therefore we could detect the distribution of skewed loci along the entire genome and identify the association between quantitative traits and segregation loci via genetic mapping in an interspecific BC1 P. tomentosa family. Furthermore, the genetic nature and pos-sible causes of these segregation distortions for differentiation between female and male parents were also discussed. 相似文献