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131.
Transformation of recalcitrant turfgrass cultivars through improvement of tissue culture and selection regime 总被引:3,自引:0,他引:3
M.X. Cao J.Q. Huang Y.L. He S.J. Liu C.L. Wang W.Z. Jiang Z.M. Wei 《Plant Cell, Tissue and Organ Culture》2006,85(3):307-316
Tissue culture techniques, medium composition, pH value and targeted tissues, agroinfection and co-culture conditions, selection process were optimized for efficient turfgrass transformation. A highly regenerable callus lines were produced in callus induction medium modified from N6 basal medium. Six-week-old calluses were cultured on Pre-regeneration medium I for 4 days and then subjected to Agrobacterium tumefaciens. After co-cultivation at 20±1 °C in a 16 h light/8 h darkness for 3 days, the calluses were cultured on non-selective Pre-regeneration medium II supplemented with 400 mg l−1 l-cysteine for 7 days. Plantlets were regenerated on the Regeneration medium without selection pressure. A selection pressure was given to the regenerated plantlets when they were rooted on the Plantlet rooting medium. Roots appeared within 8–12 days in putative transformed plantlets. Resistant plants obtained were phenotypically normal and fully fertile. Chemical and molecular analyses confirmed that foreign genes were successfully introduced into the genome of perennial ryegrass or tall fescue. The transformation efficiency can attain 23.3% in perennial ryegrass. 相似文献
132.
Effects of culling on badger Meles meles spatial organization: implications for the control of bovine tuberculosis 总被引:5,自引:2,他引:3
133.
Relationships of Exodontiella, a non-alysiine, exodont member of the family Braconidae (Insecta, Hymenoptera) 总被引:1,自引:0,他引:1
Robert A. Wharton Matthew J. Yoder Joseph J. Gillespie John C. Patton & Rodney L. Honeycutt 《Zoologica scripta》2006,35(4):323-340
The placement of Exodontiella Wharton is re-examined in light of the discovery of four additional individuals. Genomic DNA was extracted from one of the individuals, the D2 expansion segment of the 28S rRNA gene was sequenced, and the sequence compared to selected taxa within the Braconidae. Based on the molecular data and the morphological study, Exodontiella is formally transferred from the Opiinae to the Gnamptodontinae. The genus and its included species are redescribed. 相似文献
134.
Alejandro Márquez J. E. Maldonado S. González M. D. Beccaceci J. E. Garcia J. M. B. Duarte 《Conservation Genetics》2006,7(4):563-575
The marsh deer is the largest neotropical cervid with morphological and ecological adaptations to wetlands and riparian habitats. Historically, this now endangered species occupied habitats along the major river basins in South America, ranging from southern Amazonia into northern Argentina to the Paraná river delta. This particularly close association with wetlands makes marsh deer an excellent species for studying the effects of Pleistocene climatic changes on their demographic and phylogeographic patterns. We examined mitochondrial DNA variation in 127 marsh deer from 4 areas distributed throughout the Río de la Plata basin. We found 17 haplotypes in marsh deer from Brazil, Bolivia and Argentina that differed by 1–8 substitutions in a 601 bp fragment of mitochondrial control region sequence, and 486 bp of cytochrome b revealed only 3 variable sites that defined 4 haplotypes. Phylogeny and distribution of control region haplotypes suggest that populations close to the Pantanal area in central Brazil underwent a rapid population expansion and that this occurred approximately 28,000–25,000 years BP. Paleoclimatic data from this period suggests that there was a dramatic increase for precipitation in the medium latitudes in South America and these conditions may have fostered marsh deer’s population growth. 相似文献
135.
Thirty‐two polymorphic microsatellite loci (29 novel, 3 cross‐species) are characterized in the creek chub, Semotilus atromaculatus, a widespread and abundant North American minnow. Novel repeat‐containing sequences were isolated using a standard microsatellite enrichment procedure. A set of di‐, tri‐, and tetranucleotide markers with allele numbers ranging from two 16 are now available for estimating relatedness within and among populations in this ecologically important species. 相似文献
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137.
Phytochemistry Reviews - Following decades of tight restrictions, recent legislative adjustments have decriminalized the use of products derived from cannabis (Cannabis sativa L.) in many countries... 相似文献
138.
Rogers Ashleigh J. Weisler Marshall I. 《Human ecology: an interdisciplinary journal》2022,50(1):141-165
Human Ecology - The windward-leeward dichotomy is an important biogeographical distinction when investigating prehistoric island colonisation, settlement patterns, site use, and subsistence... 相似文献
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