Elucidation of the relationship between yield and heading date using CRISPR/Cas9 system-induced mutation in the flowering pathway across a large latitudinal gradient

This study documents chemical denudation rates (CDR) in the Canadian Shield and Interior Platform. It focuses on the dissolved chemistry of rivers flowing into the Hudson, James, and Ungava bays (HJUB). Major ions, strontium, neodymium, and dissolved organic carbon (DOC) concentrations were monitored in four rivers (Koksoak, Great Whale, La Grande, and Nelson). Six other rivers flowing into the HJUB were sampled during baseflow and snowmelt conditions. The rivers of the Canadian Shield exhibit major cation concentrations ranging between 62 and 360 µmol/L, [Nd] of 0.57–4.72 nmol/L, and variable [DOC] of 241–1777 µmol/L. In comparison, the Nelson River (Interior Platform) shows higher major cation concentrations (1200–2276 µmol/L), lower [Nd] (0.14–0.45 nmol/L), and intermediate [DOC] (753–928 µmol/L). Altogether, the studied rivers export 8 × 106 t/year of dissolved major cations and 50 t/year of dissolved Nd towards the HJUB. Basin-scale rock denudation rates (RDR) range from 1.0 to 5.3 t·km–2·year–1 and are essentially controlled by lithology, as illustrated by the relationship established between RDR and the proportion of sedimentary and volcanic rocks (%S + %V) within the basins: RDR = 0.08(%S + %V) + 0.9. In contrast, dissolved Nd exports (and likely other insoluble elements) seem to be dependent upon organic matter leaching, as illustrated by the empirical coupling between Nd and DOC exports. These fluxes decrease northwards, likely in response to the hydroclimatic gradient. The CDR evaluated within the Canadian Shield are among the lowest on the planet, and the alkalinity generated by rock weathering remains small with respect to DOC exports.

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The relationship between geographic area and the latitudinal gradient in species richness in New World birds

Evolutionary Ecology ◽

10.1023/a:1018451916734 ◽

1997 ◽

Vol 11 (2) ◽

pp. 195-204 ◽

Cited By ~ 29

Author(s):

Tim M. Blackburn ◽

Kevin J. Gaston

Keyword(s):

Species Richness ◽

New World ◽

Latitudinal Gradient ◽

Geographic Area ◽

New World Birds ◽

The Relationship

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Comparative Mapping of the Barley Ppd-H1 Photoperiod Response Gene Region, Which Lies Close to a Junction Between Two Rice Linkage Segments

Genetics ◽

10.1093/genetics/161.2.825 ◽

2002 ◽

Vol 161 (2) ◽

pp. 825-834

Author(s):

Roy P Dunford ◽

Masahiro Yano ◽

Nori Kurata ◽

Takuji Sasaki ◽

Gordon Huestis ◽

...

Keyword(s):

Comparative Mapping ◽

Distal Part ◽

Heading Date ◽

Rice Chromosome ◽

Photoperiod Response ◽

Rflp Markers ◽

Response Gene ◽

The Relationship ◽

Equivalent Region ◽

Search For Homologs

Abstract Comparative mapping of cereals has shown that chromosomes of barley, wheat, and maize can be described in terms of rice “linkage segments.” However, little is known about marker order in the junctions between linkage blocks or whether this will impair comparative analysis of major genes that lie in such regions. We used genetic and physical mapping to investigate the relationship between the distal part of rice chromosome 7L, which contains the Hd2 heading date gene, and the region of barley chromosome 2HS containing the Ppd-H1 photoperiod response gene, which lies near the junction between rice 7 and rice 4 linkage segments. RFLP markers were mapped in maize to identify regions that might contain Hd2 or Ppd-H1 orthologs. Rice provided useful markers for the Ppd-H1 region but comparative mapping was complicated by loss of colinearity and sequence duplications that predated the divergence of rice, maize, and barley. The sequences of cDNA markers were used to search for homologs in the Arabidopsis genome. Homologous sequences were found for 13 out of 16 markers but they were dispersed in Arabidopsis and did not identify any candidate equivalent region. The implications of the results for comparative trait mapping in junction regions are discussed.

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Persistence of dry matter yield among New Zealand perennial ryegrass (Lolium perenne L.) cultivars: insights from a long-term data set

Journal of New Zealand Grasslands ◽

10.33584/jnzg.2015.77.463 ◽

2015 ◽

Vol 77 ◽

pp. 177-184 ◽

Cited By ~ 3

Author(s):

D.F. Chapman ◽

P.D. Muir ◽

M.J. Faville

Keyword(s):

New Zealand ◽

Perennial Ryegrass ◽

Dry Matter ◽

Heading Date ◽

Early Years ◽

Grass Species ◽

Data Set ◽

High Performing ◽

Wide Range ◽

The Relationship

Persistence of herbage yield is an important productivity trait of grass species and cultivars in New Zealand pastures. However, relatively little is known about genetic variation in this trait, principally because few studies comparing yield have continued beyond 3 years. This paper reports results from a comparison of 25 perennial ryegrass cultivars representing a wide range of functional types and genetic backgrounds conducted under sheep grazing in a summer-dry environment. Dry matter (DM) yield was measured for the first 3 years after sowing, then again in years seven and eight post-sowing, and in year ten post-sowing. Endophyte DNA fingerprinting conducted mid-way through year seven confirmed that, with one exception, ryegrass populations remained true-to-type in the cultivars sown with novel endophyte strains. The cultivar effect on DM yield was statistically significant in all measurement periods. Differences in yields among cultivars in years seven and eight were significantly and positively correlated with yield differences in years one to three (r=0.685 to 0.831 depending on which year contrasts were used). Thus, high-performing cultivars in the early years of the trial were also generally highperforming cultivars in years seven and eight, and vice-versa, indicating a high degree of yield stability in perennial ryegrass cultivars. Yield differences did not appear to be related to differences in cultivar heading date, ploidy, endophyte status, or genetic background. The relationship between yield in year ten and yields in years one to three was much weaker (r=0.392) than the relationship in years seven and eight. Possible reasons for this are discussed. Keywords: Perennial ryegrass; traits; persistence

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Allochronic isolation on a latitudinal gradient in the polyphagous moth Hyphantria cunea

10.1101/2021.11.13.467162 ◽

2021 ◽

Author(s):

Emily N Black ◽

Jarrett D Blair ◽

Karin R.L. van der Burg ◽

Katie E Marshall

Keyword(s):

Latitudinal Gradient ◽

Morphological Differentiation ◽

Latitudinal Gradients ◽

Reproductive Timing ◽

Hyphantria Cunea ◽

Sympatric Populations ◽

Fall Webworm ◽

Community Science ◽

Colour Morphs ◽

The Relationship

Allochronic speciation, where reproductive isolation between populations of a species is facilitated by a difference in reproductive timing, depends on the existence of seasonality. Seasonality is strongly driven by latitude, so there may be a relationship between latitude and divergence among populations separated by life history timing. Here we explore the relationship between allochronic speciation and latitude using Hyphantria cunea (the fall webworm), a Lepidopteran defoliator with red and black colour morphs that may be undergoing an incipient allochronic speciation. We annotated >9000 community science observations of fall webworm to model colour morph phenology and differences in phenotype across North America. We also examined the physiology of two sympatric populations to determine differences in diapause intensity. We found the fall webworm is multivoltine with differing numbers of generations between colour morphs at lower latitudes, and univoltine at latitudes higher than 41°. This shift to univoltism correlated with a decline in morphological differentiation. This shows that conditions at lower latitudes facilitate greater divergence in an incipient allochronic speciation potentially due to longer reproductive seasons allowing for greater mismatches in generations. Our results demonstrate how latitude affects allochronic speciation, and how sympatric speciation along latitudinal gradients contributes to trends in global biodiversity.

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Interstellar gas in the central region of the Galaxy

Symposium - International Astronomical Union ◽

10.1017/s0074180900101032 ◽

1967 ◽

Vol 31 ◽

pp. 239-251 ◽

Cited By ~ 3

Author(s):

F. J. Kerr

Keyword(s):

Central Region ◽

Galactic Plane ◽

Neutral Hydrogen ◽

Continuum Emission ◽

Galactic Centre ◽

Interstellar Gas ◽

Hydrogen Recombination ◽

The Galaxy ◽

Centre Region ◽

The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Choosing a Markov blanket

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002632 ◽

2020 ◽

Vol 43 ◽

Author(s):

Thomas Parr

Keyword(s):

Markov Blanket ◽

Target Article ◽

The Relationship

Abstract This commentary focuses upon the relationship between two themes in the target article: the ways in which a Markov blanket may be defined and the role of precision and salience in mediating the interactions between what is internal and external to a system. These each rest upon the different perspectives we might take while “choosing” a Markov blanket.

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