Genetic parameters of growth and stem quality traits for jack pine second-generation progeny tested in New Brunswick

2015 ◽  
Vol 45 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Y.H. Weng ◽  
P. Lu ◽  
G.W. Adams ◽  
M.S. Fullarton ◽  
K.J. Tosh

Genetic variation and time trends for growth and stem quality traits were evaluated in jack pine (Pinus banksiana Lamb.) second-generation progeny tests. The study was based on a large dataset, involving 275 half-sib families and 17 field trials, planted across New Brunswick, Canada. Growth was indicated by cumulative tree height (HT) measured at trial ages from 5 to 20 years, and stem quality was evaluated on stem straightness (SST) and stem forking (SF). Results indicated that both HT and SST were moderately genetically controlled, with mean individual heritability estimates of 0.14 (range: 0.03–0.30) and 0.16 (range: 0.10–0.25), respectively, which were lower than those estimates from the first-generation progeny tests. Heritability estimates for HT increased from trial ages of 5 to 10 years and then remained stable, whereas for SST, heritability estimates showed a “Λ” shape with the highest value occurring at trial age of 15 years. HT measurements at trial ages of 5 to 10 years were highly predictive of HT growth at 15 to 20 years, and similarly, SST assessment at 10 years correlated well with assessment at 20 years. Estimates of genetic correlation between HT and SST were positively and moderately strong, which contrasted with the moderately negative genetic correlation between the two traits in the first-generation progeny. Heritability estimates for SF were generally low (mean [Formula: see text] = 0.06) and remained constant over time. SF was essentially not genetically correlated with HT or SST. Family-by-site interactions were weak for HT and SST over the trial ages but were strong for SF at trial age of 10 years or older. The potential impact of selection on genetic architecture of growth and stem quality traits in advanced generation jack pine breeding populations and on breeding and selection strategies was discussed.

New Forests ◽  
2008 ◽  
Vol 36 (3) ◽  
pp. 285-298 ◽  
Author(s):  
Y. H. Weng ◽  
K. Tosh ◽  
G. Adam ◽  
M. S. Fullarton ◽  
C. Norfolk ◽  
...  

Genome ◽  
1994 ◽  
Vol 37 (1) ◽  
pp. 1-11 ◽  
Author(s):  
M. A. Fieldes

Seed of flax (Linum usitatissimum) were treated for short durations with 5-azacytidine and the direct and heritable effects of the treatments on plant growth and development in general and, more specifically, on the contrasting phenotypes of Durrant's large and small genotrophs were examined. 5-Azacytidine induced a reduction in the height of the plants grown from treated seed. Twenty-two percent of the first generation progeny of these plants also had short phenotypes and, in most cases, the short phenotype was stably and uniformly inherited by the second generation progeny of the short, first generation plants. Treatment also induced a marked decrease in the flowering age in a few of the first generation plants that was also transmitted to their second generation progenies. The effects seen in the progeny generations suggest that most, if not all, of the heritable changes induced by the treatment are epigenetic. Several differences were seen between the large and small genotrophs, which indicate that the genome of the small genotroph is less susceptible, than the genome of the large genotroph, to 5-azacytidine induced heritable alterations.Key words: flax genotrophs, 5-azacytidine, height, flowering.


2004 ◽  
Vol 80 (1) ◽  
pp. 127-133 ◽  
Author(s):  
Bryce McInnis ◽  
Kathleen Tosh

The New Brunswick Tree Improvement Council analyzed 20-year data from plantations of unimproved and first generation improved black spruce (Picea mariana [Mill.] BSP) and jack pine (Pinus banksiana Lamb.). STAMAN, a computer model, conservatively projected an 11% merchantable volume gain at 40 years based on 20-year measurements of 36 000 trees. At age 20 years, first generation black spruce was 12% taller and 25–30% greater in total volume. Projections from over 160 000 individual measurements of height from age five to 20 years indicate that by 40 years, gains of 7–8% in height and 18–20% in total volume are likely. Ten year assessments from over 10 000 measurements of second generation black spruce indicate a 30% height gain over first generation material of the same age. For jack pine first generation material, the projections indicated a height gain of 14% and a total volume gain of over 30% at 40 years. Faster growth can provide greater volume at rotation age, a shorter rotation interval, or earlier interventions for commercial thinning. Key words: genetic gain, tree improvement, black spruce, jack pine


2016 ◽  
Vol 1 (1) ◽  
pp. 105-118
Author(s):  
Anita Pugliese ◽  
Julie Ray ◽  
Neli Esipova

This paper reports the results from Gallup’s global analysis of the likelihood of first-generation migrants, second-generation migrants and the native-born to send financial help in the form of money or goods to others inside or outside their respective country of residence. The findings in this paper are based on more than 450,000 interviews conducted through Gallup’s World Poll in 157 countries in 2012, 2013 and 2014. The sample includes more than 26,000 first-generation migrants and more than 20,000 second-generation migrants. The large sample enables Gallup to analyze first-generation migrants by the duration of their stay in their adopted country and compare their remittance behaviors with second-generation migrants and the native-born.


Author(s):  
Asaad Abdullwahab AbdulKarim ◽  
Waleed Massaher Hamad ◽  
Salah Ibrahim Hamadi

Abstract     The Frankfurt School is characterized by its critical nature and it is the result of the Marxist socialist thought as it contributed to the development of the German thought in particular and the Western thought in general through important ideas put forward by a number of pioneers in the various generations of the school and most notably through the leading pioneer in the first generation, Marcuse, and the leading pioneer of the second  generation, Habermas, whose political ideas had an important impact on global thinking and later became the basis of the attic of many critical ideas. In spite of the belief of the school members in the idea of the criticism of power and community, each had his own ideas that distinguish him from the others.


2020 ◽  
Vol 25 (1) ◽  
pp. 23-32
Author(s):  
Gerd Laux

Für die Therapie schizophrener Erkrankungen sind seit fast 60 Jahren Antipsychotika/Neuroleptika aufgrund ihrer antipsychotischen Wirkung von zentraler Bedeutung. Die Einteilung kann unter verschiedenen Gesichtspunkten erfolgen (chemische Struktur, neuroleptische Potenz, Rezeptorprofil), heute werden üblicherweise unterschieden typische (traditionelle, klassische, konventionelle) Antipsychotika der ersten Generation ‒ »First Generation Antipsychotics« (FGA) ‒ und sog. atypische (»neuere«) Neuroleptika bzw. Antipsychotika der zweiten Generation ‒»Second Generation Antipsychotics« (SGA). Hierzu zählen Aripiprazol, Asenapin, Cariprazin, Clozapin, Olanzapin, Quetiapin, Risperidon, Sertindol und Ziprasidon. Hierbei handelt es sich um keine homogene Gruppe – sowohl neuropharmakologisch (Wirkmechanismus), als auch hinsichtlich klinischem Wirkprofil und dem Nebenwirkungsspektrum bestehen z. T. erhebliche Unterschiede. Neben der Akut-Medikation ist eine Langzeitmedikation bzw. Rezidivprophylaxe mit Antipsychotika für die Rehabilitation vieler schizophrener Patienten im Sinne eines »Stresspuffers« von grundlegender Bedeutung. In Placebo-kontrollierten Studien trat bei Patienten, die über ein Jahr behandelt wurden, bei etwa 30% unter Neuroleptika ein Rezidiv auf, unter Placebo bei mehr als 70%. Für die Langzeitbehandlung bietet sich der Einsatz von Depot-Neuroleptika an, neu entwickelt wurden Langzeit-Depot-Injektionen mit Intervallen von bis zu 3 Monaten. Grundsätzlich ist die niedrigstmögliche (wirksame) Dosis zu verwenden. Im Zentrum der Nebenwirkungen (UAW) standen lange Zeit extrapyramidal-motorische Bewegungsstörungen (EPMS), mit der Einführung von Clozapin und anderen atypischen Antipsychotika der zweiten Generation gewannen andere Nebenwirkungen an Bedeutung. Hierzu zählen Gewichtszunahme, Störungen metabolischer Parameter und ein erhöhtes Risiko für Mortalität und zerebrovaskuläre Ereignisse bei älteren Patienten mit Demenz. Entsprechende Kontrolluntersuchungen sind erforderlich, für Clozapin gibt es aufgrund seines Agranulozytose-Risikos Sonderbestimmungen. Immer sollte ein Gesamtbehandlungsplan orientiert an der neuen S3-Praxisleitlinie Schizophrenie der DGPPN aufgestellt werden, der psychologische und milieu-/sozial-therapeutische Maßnahmen einschließt. Standard ist heute auch eine sog. Psychoedukation, für Psychopharmaka liegen bewährte Patienten-Ratgeber vor.


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