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The changing of sowing gravities of different varieties of wheat under conditions of conservation 全文
2006
Насіковський, В. А
The changing of sowing gravities of different varieties of wheat under conditions of conservation 全文
2006
Насіковський, В. А
The influence of different conditions of conservation to sprout and germinating power of seed varieties of wheat under conditions of conservation are expounded in the article.
显示更多 [+] 显示较少 [-]Unambiguous identification of fungi: where do we stand and how accurate and precise is fungal DNA barcoding? 全文
2020
Robert Lücking | M. Catherine Aime | Barbara Robbertse | Andrew N. Miller | Hiran A. Ariyawansa | Takayuki Aoki | Gianluigi Cardinali | Pedro W. Crous | Irina S. Druzhinina | David M. Geiser | David L. Hawksworth | Kevin D. Hyde | Laszlo Irinyi | Rajesh Jeewon | Peter R. Johnston | Paul M. Kirk | Elaine Malosso | Tom W. May | Wieland Meyer | Maarja Öpik | Vincent Robert | Marc Stadler | Marco Thines | Duong Vu | Andrey M. Yurkov | Ning Zhang | Conrad L. Schoch
ABSTRACT True fungi (Fungi) and fungus-like organisms (e.g. Mycetozoa, Oomycota) constitute the second largest group of organisms based on global richness estimates, with around 3 million predicted species. Compared to plants and animals, fungi have simple body plans with often morphologically and ecologically obscure structures. This poses challenges for accurate and precise identifications. Here we provide a conceptual framework for the identification of fungi, encouraging the approach of integrative (polyphasic) taxonomy for species delimitation, i.e. the combination of genealogy (phylogeny), phenotype (including autecology), and reproductive biology (when feasible). This allows objective evaluation of diagnostic characters, either phenotypic or molecular or both. Verification of identifications is crucial but often neglected. Because of clade-specific evolutionary histories, there is currently no single tool for the identification of fungi, although DNA barcoding using the internal transcribed spacer (ITS) remains a first diagnosis, particularly in metabarcoding studies. Secondary DNA barcodes are increasingly implemented for groups where ITS does not provide sufficient precision. Issues of pairwise sequence similarity-based identifications and OTU clustering are discussed, and multiple sequence alignment-based phylogenetic approaches with subsequent verification are recommended as more accurate alternatives. In metabarcoding approaches, the trade-off between speed and accuracy and precision of molecular identifications must be carefully considered. Intragenomic variation of the ITS and other barcoding markers should be properly documented, as phylotype diversity is not necessarily a proxy of species richness. Important strategies to improve molecular identification of fungi are: (1) broadly document intraspecific and intragenomic variation of barcoding markers; (2) substantially expand sequence repositories, focusing on undersampled clades and missing taxa; (3) improve curation of sequence labels in primary repositories and substantially increase the number of sequences based on verified material; (4) link sequence data to digital information of voucher specimens including imagery. In parallel, technological improvements to genome sequencing offer promising alternatives to DNA barcoding in the future. Despite the prevalence of DNA-based fungal taxonomy, phenotype-based approaches remain an important strategy to catalog the global diversity of fungi and establish initial species hypotheses.
显示更多 [+] 显示较少 [-]То increase sowing quality of iattuce seeds ways of decreassing him the matrix differences 全文
2006
Лещук, Н. В
То increase sowing quality of iattuce seeds ways of decreassing him the matrix differences 全文
2006
Лещук, Н. В
Revealed main point of formation the matrix differences of lettuce seeds characteristics (Lactuca sativa L.), its correlation with other categories of heterogeneity. It’s been shown the ways of decreasing of the matrix differences of lettuce seeds characteristics with the aim to increase sowing quality of seeds.
显示更多 [+] 显示较少 [-]То increase sowing quality of iattuce seeds ways of decreassing him the matrix differences 全文
2006
Н. В. Лещук
Revealed main point of formation the matrix differences of lettuce seeds characteristics (Lactuca sativa L.), its correlation with other categories of heterogeneity. It’s been shown the ways of decreasing of the matrix differences of lettuce seeds characteristics with the aim to increase sowing quality of seeds.
显示更多 [+] 显示较少 [-]New Winter Wheat Varieties Productivity Subject to the Terms of Sowing 全文
2009
Уліч, Л. І | Корхова, М. М | Котиніна, О. А
New Winter Wheat Varieties Productivity Subject to the Terms of Sowing 全文
2009
Уліч, Л. І | Корхова, М. М | Котиніна, О. А
Sowing dates and response to them of newly registered and perspective varieties of winter wheat were studied. Reasons provided for changing sowing dates to the later.
显示更多 [+] 显示较少 [-]New Winter Wheat Varieties Productivity Subject to the Terms of Sowing. 全文
2009
Л. І. Уліч | М. М. Корхова | О. А. Котиніна
Sowing dates and response to them of newly registered and perspective varieties of winter wheat were studied. Reasons provided for changing sowing dates to the later.
显示更多 [+] 显示较少 [-]Sowing properties of summer rape seeds depending on fertilizers and terms of harvesting 全文
2006
Юник, А. В | Новицька, Н. В | Мокрієнко, В. А
Sowing properties of summer rape seeds depending on fertilizers and terms of harvesting 全文
2006
Юник, А. В | Новицька, Н. В | Мокрієнко, В. А
In the article the results of research of sowing properties - emergence rate and laboratory germinating capacity seeds summer rape are resulted depending on variants of fertilizers and terms of harvesting.
显示更多 [+] 显示较少 [-]Sowing properties of summer rape seeds depending on fertilizers and terms of harvesting 全文
2006
А. В. Юник | Н. В. Новицька | В. А. Мокрієнко
In the article the results of research of sowing properties - emergence rate and laboratory germinating capacity seeds summer rape are resulted depending on variants of fertilizers and terms of harvesting.
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