Aulacopleurine trilobites from the Llandovery of northwestern Canada

1995 ◽  
Vol 69 (2) ◽  
pp. 326-340 ◽  
Author(s):  
J. M. Adrain ◽  
B. D. E. Chatterton
Keyword(s):  
Northwest Territories ◽  
Early Growth ◽  
Growth Stages ◽  
Mackenzie Mountains ◽  
Relationship Of ◽  
The Relationship

Aulacopleurine trilobites from Llandovery strata of the Whittaker Formation in the central Mackenzie Mountains, Northwest Territories, Canada, include Aulacopleura andersoni n. sp., Aulacopleura? ranfordi n. sp., and Songkania smithi n. sp. The subfamily Aulacopleurinae consists of only the genera Aulacopleura Hawle and Corda, 1847, and Songkania Chang, 1974, characterized by smooth, broad early growth stages and holaspides having expanded frontal and genal areas, covered with dense caecal pits, but usually very subdued tuberculate sculpture. The relationship of Aulacopleura? ranfordi and A.? reedi Přibyl, 1947, to the remainder of species assigned to the genus is ambiguous.

Soybean seed coat cup unloading on plants with low-raffinose, low-stachyose seeds

2009 ◽  
Vol 19 (3) ◽  
pp. 145-153 ◽  
Author(s):  
Suzanne M. Kosina ◽  
Alexander Castillo ◽  
Steven R. Schnebly ◽  
Ralph L. Obendorf
Keyword(s):  
Seed Coat ◽  
Soybean Seed ◽  
Soluble Carbohydrates ◽  
Growth Stages ◽  
In Planta ◽  
Plant Growth Stages ◽  
Soybean Plants ◽  
Soybean Seed Coat ◽  
Relationship Of ◽  
The Relationship

AbstractSucrose, raffinose and stachyose accumulate in soybean [Glycine max L. (Merrill)] embryos during seed maturation. To determine the relationship of plant maternal composition on seed composition, soluble carbohydrates in three 1-cm2 leaf punches at three plant growth stages (R2, R3, R6) and in seed coat cup exudates in planta were analysed at four 30-min intervals on soybean plants (R5) with low-raffinose, low-stachyose (LRS) seeds expressing the mutant stc1 phenotype; low-raffinose, low-stachyose and low-phytin (LRSP1, LRSP2) seeds expressing the mutant mips phenotype; or normal raffinose, stachyose and phytin (CHECK) seeds expressing the Stc1 and Mips phenotype. Leaf sucrose (23.6 μg cm− 2), myo-inositol (9.3 μg cm− 2), d-chiro-inositol (6.7 μg cm− 2), d-ononitol (0.76 μg cm− 2), d-pinitol (50.1 μg cm− 2) and total soluble carbohydrates (107.1 μg cm− 2) were not significantly different between phenotypes. d-chiro-Inositol, myo-inositol, d-pinitol and sucrose were unloaded from soybean seed coat cups in planta at decreasing rates over the four sequential periods of sampling. Unloading rates of sucrose and myo-inositol were highest for LRS, d-pinitol was highest for LRSP2, and d-chiro-inositol was not different between LRS, LRSP1, LRSP2 and CHECK. Free cyclitols were 60% of total soluble carbohydrates in leaves and 20% in seed coat cup exudates. Except for sucrose and d-pinitol, seed phenotype had little influence on the composition of compounds unloaded from seed coats to maturing embryos of low-raffinose, low-stachyose seeds. Maternally supplied cyclitols may contribute, in part, to changes in the composition of cyclitol galactosides stored in mature seeds.

scholarly journals Relationship of Whitefly Population Build up with the Spread of TYLCV on Eight Tomato Varieties

1970 ◽  
Vol 4 (1) ◽  
pp. 67-74 ◽  
Author(s):  
AHMA Rahman ◽  
AM Akanda ◽  
AKM Ashraful Alam
Keyword(s):  
Early Stage ◽  
Tomato Yellow Leaf ◽  
Growth Stages ◽  
Whitefly Population ◽  
Key Words Prevalence ◽  
Virus Prevalence ◽  
Tomato Field ◽  
Relationship Of ◽  
Leaf Curl Virus ◽  
The Relationship

The performance of eight tomato varieties namely BARI-T1 (Manik), BARI-T2 (Ratan), BARI-T4, BARI-T5, BARI-T6 (Apurba), BARI-T7 (Chaity), BARI-T11 and BARI-T12 were evaluated in respect to prevalence and spread of TYLCV (Tomato Yellow Leaf curl Virus) in relation to whitefly population buildup in the field. Data were collected on the three growth stages of the plant namely early (transplanting to first flowering) mid (first flowering to first harvesting) and late (first harvesting to last harvesting). The virus prevalence percentage in eight tomato varieties varied depending on early, mid and late stage of infection as well as tomato varieties. It ranged from 42 to 69%. There was a poor and insignificant quadratic polynomial relationship (y = -0.0059x 2 + 0.2826x – 1.5378 & R2 = 0.0962) between temperature and whitefly population build up in tomato field. The relationship between relative humidity and whitefly population build up in the field was found significant but negatively correlated (y = - 0.0321x 2 +4.5518x – 159.44 (R2 = 0.6769). The increase of whitefly population in the field was positively correlated with the spread of TYLCV in the tomato field (y = - 0.0002x 2 + 0.0297x + 1.0626 & R2 = 0.663). The highest and lowest prevalence of TYLCV was recorded in BARI-T6 and BARI-T11, respectively. In all the varieties, virus prevalence was found higher at mid stage followed by late and early stage of infection. Key words: Prevalence, TYLCV, whitefly.

scholarly journals Metabolite Profiles of the Relationship between Body Mass Index (BMI) Milestones and Metabolic Risk during Early Adolescence

Metabolites ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 316
Author(s):  
Wei Perng ◽  
Mohammad L. Rahman ◽  
Izzuddin M. Aris ◽  
Gregory Michelotti ◽  
Joanne E. Sordillo ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Early Adolescence ◽  
Early Growth ◽  
Metabolic Risk ◽  
Z Score ◽  
Sex Steroid Hormone ◽  
Metabolite Profiles ◽  
Relationship Of ◽  
The Relationship

Early growth is associated with future metabolic risk; however, little is known of the underlying biological pathways. In this prospective study of 249 boys and 227 girls, we sought to identify sex-specific metabolite profiles that mark the relationship between age and magnitude of the infancy body mass index (BMI) peak, and the childhood BMI rebound with a metabolic syndrome z-score (MetS z-score) during early adolescence (median age 12.8 years). Thirteen consensus metabolite networks were generated between male and female adolescents using weighted correlation network analysis. In girls, none of the networks were related to BMI milestones after false discovery rate (FDR) correction at 5%. In boys, age and/or magnitude of BMI at rebound were associated with three metabolite eigenvector (ME) networks comprising androgen hormones (ME7), lysophospholipids (ME8), and diacylglycerols (ME11) after FDR correction. These networks were also associated with MetS z-score in boys after accounting for age and race/ethnicity: ME7 (1.43 [95% CI: 0.52, 2.34] units higher MetS z-score per 1 unit of ME7), ME8 (−1.01 [95% CI: −1.96, −0.07]), and ME11 (2.88 [95% CI: 2.06, 3.70]). These findings suggest that alterations in sex steroid hormone and lipid metabolism are involved in the relationship of early growth with future metabolic risk in males.

Influence of Herbicide Injury on the Yield Potential of Soybeans (Glycine max)

Weed Science ◽  
1980 ◽  
Vol 28 (1) ◽  
pp. 40-45 ◽  
Author(s):  
E. S. Hagood ◽  
J. L. Williams ◽  
T. T. Bauman
Keyword(s):  
Glycine Max ◽  
Early Growth ◽  
Yield Potential ◽  
Yield Response ◽  
Yield Reduction ◽  
Growth Stages ◽  
The Relationship

The relationship between herbicide injury and soybean [Glycine max(L.) Merr. ‘Amsoy 71’] yield response was studied under weed free conditions at three locations. Reduced crop vigor at early growth stages was not an adequate indicator of yield response. Yield reduction was greater when soybean stand was reduced by herbicides than when stand was reduced to the same level by hand thinning. Yield response was a function of the degree and persistence of crop vigor reduction in a reduced stand of soybeans.

Performance of BAS 9052 Applied to Johnsongrass (Sorghum halepense) and Soybeans (Glycine max)

Weed Science ◽  
1983 ◽  
Vol 31 (6) ◽  
pp. 796-800 ◽  
Author(s):  
E. James Retzinger ◽  
R. Larry Rogers ◽  
Ronald P. Mowers
Keyword(s):  
Glycine Max ◽  
Growth Stage ◽  
Soybean Seed ◽  
Moisture Stress ◽  
Sorghum Halepense ◽  
Growth Stages ◽  
Exponential Equation ◽  
Yield Increase ◽  
Relationship Of ◽  
The Relationship

The performance of BAS 9052 {2-[1-(ethoxyimino)-butyl]-5-[2-(ethylthio)-propyl]-3-hydroxy-2-cyclohexen-1-one} was evaluated when applied postemergence to rhizome and seedling johnsongrass [Sorghum halepense(L.) Pers. # SORHA] in soybeans [Glycine max(L.) Merr. ‘Bragg’ and ‘Centennial’] when the soybeans had four or five trifoliate leaves (V3 to V4 stages) or when they had six to eight trifoliate leaves (V5 to V7 growth stages). The degree of weed control was more strongly associated with rainfall conditions than with the size of the johnsongrass. An exponential equation was used to describe the relationship of soybean seed yield to BAS 9052 rate. BAS 9052 applications of 0.28 kg ai/ha provided an estimated 98% of the potential soybean yield increase when rainfall was adequate but, 0.41 kg ai/ha was required when the plants were grown under moisture stress. Soybean yields were increased by 260 kg/ha when BAS 9052 was applied at the V3 to V4 compared to the V5 to V7 growth stage.

EFFECT OF FERMENTATION TIME IN THE ARTIFICIAL RUMEN ON THE RELATIONSHIP OF IN VITRO DIGESTIBILITY TO DIGESTIBILTY AND INTAKE OF HAY BY SHEEP

1968 ◽  
Vol 48 (3) ◽  
pp. 361-372 ◽  
Author(s):  
J. E. Troelsen ◽  
J. M. Bell
Keyword(s):  
In Vitro Digestion ◽  
In Vitro Digestibility ◽  
Growth Stages ◽  
Fermentation Time ◽  
Assay Procedure ◽  
Relationship Of ◽  
Physical And Chemical ◽  
The Relationship

The digestibility and intake of several kinds of hay at several growth stages were measured with sheep. The in vitro digestibility was determined by a two-stage procedure. Because the in vitro digestibility of dry matter was unduly affected by a high solubility of the ash fraction, organic matter digestibility was the preferred criterion. In vitro digestibility was measured after fermentation times of 6, 12, 24, 48 or 96 hr. Significant correlations (P < 0.001) were found between in vivo and in vitro digestibility at each of these times. Near-maximal correlations occurred for most hays at 48 to 96 hr. Regressions for each duration were calculated and were used to estimate durations where equal in vitro and in vivo values should occur. Differences between kinds of hay and interactions between growth stages hindered improvement of the assay procedure by simple adjustments in fermentation duration.Optimal estimates of digestibility and intake occurred at the same fermentation durations. This was attributed to the recognized relationship between digestibility and intake of forage. A change of one unit in the in vitro digestibility was associated with an 18% greater change in intake of grass hay than of alfalfa hay, but at 70% digestibility both kinds of hay were eaten in equal amounts.The optimal fermentation duration for a general assay to predict digestibility and intake was about 48 hr. Further improvements appeared to require knowledge about differences in kinds and growth stages of hay, in their physical and chemical reaction to in vivo mastication and digestion as compared with grinding and in vitro digestion.

A Method of distinguishing the larval Stages of Agriotes sputator (L.) (Col., Elaterid.)

1950 ◽  
Vol 41 (2) ◽  
pp. 395-413 ◽  
Author(s):  
Joan F. Basden
Keyword(s):  
Growth Stage ◽  
Early Stage ◽  
Growth Stages ◽  
Optimum Size ◽  
Quick Method ◽  
Stage Number ◽  
Larval Stages ◽  
Number Of Teeth ◽  
Relationship Of ◽  
The Relationship

The different instars of Agriotes sputator larvae cannot be distinguished by measurements of total length or of various parts of the wireworm.The number of teeth on the mesothoracic and abdominal spiracles increases with age, and an examination of 700 wireworms showed that the average numbers of teeth on the two thoracic or on all the abdominal spiracles fell into eight groups. These criteria were valid for populations collected at different times of the year.The number of teeth on the thoracic spiracles of a larva in any particular group approximates to that on the abdominal spiracles of a larva in the next larger group.The eight groups formed by counting either the thoracic or the abdominal spiracle teeth represent growth stages and not necessarily instars.The larvae may sometimes moult without growth, a phenomenon probably caused by an inadequate supply of food. At such an ecdysis the number of spiracle teeth does not increase.The larvae pupate after attaining an optimum size, and reach this size in seven or eight growth stages.A quick method of determining the growth stage to which a larva belongs is given, whereby more than 80 per cent, of the larvae are placed in their correct growth stages by counting the teeth on one spiracle only ; for less than 1 per cent, of the larvae is it necessary to examine as many as five spiracles ; an accuracy of more than 97 per cent, can be maintained.The possibility of determining the relationship of growth stage and age is discussed.The division of the larvae into those which will pupate after seven, and those which will pupate after eight growth stages is apparent at a very early stage in the life history. One larva was found which appeared to be in its ninth growth stage.The cause of this difference in growth stage number is unknown. It may be due to the size of the egg, to the time of the year at which hatching occurs, or to heredity.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
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.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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