A high-yielding Mexican semi-dwarf wheat and the relationship of yield to harvest index and other varietal characteristics

1970 ◽  
Vol 10 (44) ◽  
pp. 350 ◽  
Author(s):  
JR Syme

A study has been made of a Mexican semi-dwarf wheat (Lerma Rojo X Norim 10- Brevor 14) Andes3, local accession number WW 15. In 53 trials, over two seasons and a wide range of conditions, this has shown a marked grain yield superiority over other Mexican and Australian varieties when grown in high yielding environments. Nine varieties in five trials were sampled at maturity. Varietal grain yield was highly correlated with harvest index and with the number of grains set relative to straw and chaff weight. WW 15 excelled in both ratios, and combined a dense ear population with many grains per ear.

Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.


1992 ◽  
Vol 262 (6) ◽  
pp. S9 ◽  
Author(s):  
E Bowdan

Regulation of feeding is a fundamental element of homeostasis. This is reflected in the similarity of control mechanisms in a wide range of animals, including insects and humans. A close examination of feeding behavior can illuminate the physiological processes driving regulation. A simple, inexpensive method for recording fine details of feeding by caterpillars is described. Possible experiments, interpretation of the data, and the relationship of observations to the underlying physiology, are outlined.


1998 ◽  
Vol 44 (12) ◽  
pp. 1115-1136 ◽  
Author(s):  
M J Butler ◽  
A W Day

The relationship of polyketide melanogenesis molecular biology to that of nonmelanin-producing pathways in a wide range of fungi and other organisms is discussed. Analytical methods and fundamental properties of melanins are discussed and fungal melanin properties are compared with those of animal and bacterial melanins. The enzymatic degradation of melanins by lignin peroxidases is described.Key words: fungal melanin, polyketide melanin, DHN melanin, melanin degradation, melanin properties, melanin analysis.


2021 ◽  
Author(s):  
◽  
Avril Macfarlane

<p>There is a growing concern internationally about levels of income inequality, and the negative effect this has on the functioning of societies both in terms of productivity and social harmony. An unexpected contributor to inequality is assortative mating - the phenomenon of “like marrying like”. Educational attainment is highly correlated with income; when two highly educated people partner and form a household they are more likely to appear at the top of the household income distribution, while couples with only primary or incomplete secondary education appear at the bottom. Therefore the greater the propensity to mate assortatively the more unequal the distribution of household income becomes.   I ask two questions of the relationship between educational assortative mating and household income inequality. Firstly, how do countries (in Europe) differ in their degree of educational assortative mating? Secondly, what is the evidence that such differences are reflected in indicators of household income inequality?   My study differs from the prevailing approaches to this question by taking a geographical approach. Instead of comparing a single country over time and monitoring the correspondence between assortative mating and income inequality, I compare a wide range of countries, using a uniform instrument, at one point in time. In order to do so I draw on the unit records of 29 countries from the European Social Survey administered in 2012.   From these unit record data I have been able to identify two important patterns. Firstly, there is a clear presence of educational assortative mating in each country. However, the degree differs and it does so primarily as a reflection of the overall level of education in the country. Rising levels of education lower the returns for education, in turn making assortative mating comparatively less attractive. As a result, the level of assortative mating, compared to what would be expected under random conditions, is lower in highly educated nations. The lowered level of assortative mating in highly educated nations reduces the barriers to social mobility through marriage for those without university educations. Consequently, household income inequality is seen to be intrinsically related to assortative mating, although the outcomes can be mitigated by redistribution policies.</p>


2021 ◽  
Author(s):  
◽  
Avril Macfarlane

<p>There is a growing concern internationally about levels of income inequality, and the negative effect this has on the functioning of societies both in terms of productivity and social harmony. An unexpected contributor to inequality is assortative mating - the phenomenon of “like marrying like”. Educational attainment is highly correlated with income; when two highly educated people partner and form a household they are more likely to appear at the top of the household income distribution, while couples with only primary or incomplete secondary education appear at the bottom. Therefore the greater the propensity to mate assortatively the more unequal the distribution of household income becomes.   I ask two questions of the relationship between educational assortative mating and household income inequality. Firstly, how do countries (in Europe) differ in their degree of educational assortative mating? Secondly, what is the evidence that such differences are reflected in indicators of household income inequality?   My study differs from the prevailing approaches to this question by taking a geographical approach. Instead of comparing a single country over time and monitoring the correspondence between assortative mating and income inequality, I compare a wide range of countries, using a uniform instrument, at one point in time. In order to do so I draw on the unit records of 29 countries from the European Social Survey administered in 2012.   From these unit record data I have been able to identify two important patterns. Firstly, there is a clear presence of educational assortative mating in each country. However, the degree differs and it does so primarily as a reflection of the overall level of education in the country. Rising levels of education lower the returns for education, in turn making assortative mating comparatively less attractive. As a result, the level of assortative mating, compared to what would be expected under random conditions, is lower in highly educated nations. The lowered level of assortative mating in highly educated nations reduces the barriers to social mobility through marriage for those without university educations. Consequently, household income inequality is seen to be intrinsically related to assortative mating, although the outcomes can be mitigated by redistribution policies.</p>


1978 ◽  
Vol 26 (4) ◽  
pp. 383-398 ◽  
Author(s):  
A. Darwinkel

The effect of plant density on the growth and productivity of the various ear-bearing stems of winter wheat was studied in detail to obtain information on the pattern of grain production of crops grown under field conditions. Strong compensation effects were measured: a 160-fold increase in plant density (5-800 plants/m2) finally resulted in a 3-fold increase in grain yield (282 to 850 g DM/m2). Max. grain yield was achieved at 100 plants/m2, which corresponded to 430 ears/m2 and to about 19 000 grains/m2. At higher plant densities more ears and more grains were produced, but grain yield remained constant. Tillering/plant was largely favoured by low plant densities because these allowed tiller formation to continue for a longer period and a greater proportion of tillers produced ears. However, at higher plant densities more tillers/unit area were formed and, despite a higher mortality, more ears were produced. The productivity of individual ears, from main stems as well as from tillers, decreased with increasing plant density and with later emergence of shoots. In the range from 5 to 800 plants/m2 grain yield/ear decreased from 2.40 to 1.14 g DM. At 800 plants/m2 nearly all ears originated from main stems, but with decreasing plant density tillers contributed increasingly to the number of ears. At 5 plants/m2, there were 23 ears/plant and grain yield/ear ranged from 4.20 (main stem) to 1.86 g DM (late-formed stems). Grain number/ear was reduced at higher densities and on younger stems, because there were fewer fertile spikelets and fewer grains in these spikelets. At the low density of 5 plants/m2, plants developed solitarily and grain yield/ear was determined by the number of grains/ear as well as by grain wt. Above 400 ears/m2, in this experiment reached at 100 plants/m2 and more, grain yield/ear depended solely on grain number, because the wt. of grains of the various stems were similar. The harvest index showed a max. of about 44% at a moderate plant density; at this density nearly max. grain yield was achieved. At low plant densities the harvest index decreased from 45% in main stems to about 36% in late-formed stems. However, no differences in harvest index existed between the various ear-bearing stems if the number of ears exceeded 400/m2. (Abstract retrieved from CAB Abstracts by CABI’s permission)


1969 ◽  
Vol 25 (3) ◽  
pp. 711-714 ◽  
Author(s):  
Russell G. Geen ◽  
Robert George

A self-report inventory made up of items from the Buss-Durkee manifest aggressiveness scales, the Marlowe-Crowne Social Desirability Scale, and the Masculinity-Femininity scale of the Guilford-Zimmerman Temperament Survey was administered to 72 men along with a test of verbal associations to aggressive and neutral cue words. The number of aggressive associations made to aggressive cue words was highly correlated with over-all manifest aggressiveness and with two of the aggressiveness subscales. The results were discussed in terms of the relationship of aggressiveness habit strength to verbal behavior.


Author(s):  
W.S. Green

This introduction to the symposium Inclusive Design and Usability gives an overview of some of the issues and problems facing ergonomists and designers who attempt to provide access to current technologies for a wide range of user groups, particularly those who may be considered disadvantaged or handicapped. The relationship of ergonomics and design is raised.


Author(s):  
Joel Altman

This chapter examines the use of ekphrasis in early modern theatre, with particular emphasis on its effect on the stage and the relationship of ekphrastic speech to the ongoing action in which it is enunciated. It maps the parameters of ekphrasis on the early modern English stage by considering a few examples of the ways in which ekphrasis instantiates early modern theatricality. It also discusses the expressive potential of ekphrastic speech and its transmission to the listener as well as the ironic uses of ekphrasis as a mode of persuasion, whether directed to oneself, an on-stage auditor, off-stage auditors, or all three. It argues that ekphrasis creates nothing less than what it calls ‘the psyche of the play’ and explains how the unusually flexible capacity of the staged word allows it to be used for a wide range of theatrical techniques, including the usual sense of ‘word-painting’. Finally, it looks at William Shakespeare’s deployment of ekphrasis in his work such asHamlet.


2010 ◽  
Vol 33 (1) ◽  
pp. 4.1-4.32 ◽  
Author(s):  
Richard B. Baldauf ◽  
Robert B. Kaplan

Applied Linguistics is a diverse field, comprising a substantial number of sub-fields, sub-specialisations and related fields. To see that this is the case one need only examine the various hand- books and encyclopaedic references that have been published in the last ten years to see the wide range of topics that have been covered. As with many professional areas in academia, Applied Linguistics is organised around national organisations, with its international structure being a loose confederation known as the International Association of Applied Linguistics (AILA). Given these diverse academic and structural arrangements, it should not be surprising if academics within different national associations were to cluster around different interests within the field. This study explores the question of what emphases are found in various parts of the world in Applied Linguistics, and in particular, the relationship of Australian Applied Linguistics to international trends using a structural text analysis of abstracts related to Applied Linguistics as well as an historical review of the trends involved.


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