scholarly journals Genetic control of silvicultural traits in Balfourodendron riedelianum (ENGL.) ENGL.

2019 ◽  
Vol 68 (1) ◽  
pp. 73-78 ◽  
Author(s):  
B.I. Aguiar ◽  
M.L.M. Freitas ◽  
Y.R. Tavares ◽  
E.V. Tambarussi ◽  
B. Zanatto ◽  
...  

Abstract The Atlantic Forest has very high levels of biodiversity and is considered one of the most important and threatened biomes in the world. Balfourodendron riedelianum is one of the forest’s characteristic tree species that is currently under considered endangered due to timber extraction and forest fragmentation. With the goal of generating information that may contribute to the genetic conservation of B. riedelianum, genetic parameters are estimated for quantitative traits important for silviculture in a provenance and progeny test located in the Experimental Station of Luiz Antônio, São Paulo State, Brazil. The test was established in 1986 and consists of three provenances, from which open-pollinated seeds from 19 seed trees were collected. The following traits were evaluated at 32 years of age: diameter at breast height (DBH), total height (H), stem height (SH), stem straightness (SS), and forking (FOR). The estimates were carried out using the REML/BLUP method. Significant genetic variation among progenies was detected for all traits (except SH) and between provenances for DBH. The coefficient of individual genetic variation (CVgi) ranged from 2.5 to 9.5 %. The mean heritability among progeny ( $h_f^2$ ) was substantial for DBH (0.44) and FOR (0.36), enabling the selection of families with the highest DBH and lowest FOR for population improvement. Genotypic and phenotypic correlations among traits were also found. We conclude that there is genetic variability in the population that can be exploited in future breeding programs and for the genetic conservation of the species.

2004 ◽  
Vol 155 (5) ◽  
pp. 142-145 ◽  
Author(s):  
Claudio Defila

The record-breaking heatwave of 2003 also had an impact on the vegetation in Switzerland. To examine its influences seven phenological late spring and summer phases were evaluated together with six phases in the autumn from a selection of stations. 30% of the 122 chosen phenological time series in late spring and summer phases set a new record (earliest arrival). The proportion of very early arrivals is very high and the mean deviation from the norm is between 10 and 20 days. The situation was less extreme in autumn, where 20% of the 103 time series chosen set a new record. The majority of the phenological arrivals were found in the class «normal» but the class«very early» is still well represented. The mean precocity lies between five and twenty days. As far as the leaf shedding of the beech is concerned, there was even a slight delay of around six days. The evaluation serves to show that the heatwave of 2003 strongly influenced the phenological events of summer and spring.


2019 ◽  
Vol 37 (2) ◽  
pp. 204-209
Author(s):  
Valter C de Andrade Júnior ◽  
Amanda G Guimarães ◽  
Tiago D Firme ◽  
Aline Aparecida A Costa ◽  
Márcia Regina da Costa ◽  
...  

ABSTRACT Correlations and path analysis between characteristics can aid the selection of important attributes in breeding programs. Thus, the objective of this work was to perform genotypic, phenotypic correlations and path analysis under commercial yield of garlic bulbs, depending on morphological and agronomic variables. The experiment was carried out in 2017 at the Universidade Federal dos Vales do Jequitinhonha e Mucuri and Universidade Federal de Lavras, using ten garlic genotypes, eight trials and two commercial cultivars, Caçador and Jonas. We evaluated: plant height; number of leaves, total bulb number; total bulb mass, total bulb yield, marketable bulb yield and number of cloves per bulb. The genotypic and phenotypic correlations were positive and significant between marketable yield of bulbs with bulb mass, total yield and number of cloves per bulb, indicating that selection based on these characteristics will help increase the yield of garlic. However, only the number of cloves per bulb had a direct effect and a relevant indirect effect on the marketable yield of garlic.


2019 ◽  
Vol 97 (7) ◽  
pp. 2769-2779 ◽  
Author(s):  
Michelle M Judge ◽  
Thierry Pabiou ◽  
Jessica Murphy ◽  
Stephen B Conroy ◽  
P J Hegarty ◽  
...  

Abstract The ability to alter the morphology of cattle towards greater yields of higher value primal cuts has the potential to increase the value of animals at slaughter. Using weight records of 14 primal cuts from 31,827 cattle, the objective of the present study was to quantify the extent of genetic variability in these primal cuts; also of interest was the degree of genetic variability in the primal cuts adjusted to a common carcass weight. Variance components were estimated for each primal cut using animal linear mixed models. The coefficient of genetic variation in the different primal cuts ranged from 0.05 (bavette) to 0.10 (eye of round) with a mean coefficient of genetic variation of 0.07. When phenotypically adjusted to a common carcass weight, the coefficient of genetic variation of the primal cuts was lesser ranging from 0.02 to 0.07 with a mean of 0.04. The heritability of the 14 primal cuts ranged from 0.14 (bavette) to 0.75 (topside) with a mean heritability across all cuts of 0.48; the heritability estimates reduced, and ranged from 0.12 (bavette) to 0.56 (topside), when differences in carcass weight were accounted for in the statistical model. Genetic correlations between each primal cut and carcass weight were all ≥0.77; genetic correlations between each primal cut and carcass conformation score were, on average, 0.59 but when adjusted to a common carcass weight, the correlations weakened to, on average, 0.27. The genetic correlations among all 14 primal cut weights was, on average, strong (mean correlation of 0.72 with all correlations being ≥0.37); when adjusted to a common carcass weight, the mean of the genetic correlations among all primal cuts was 0.10. The ability of estimated breeding values for a selection of primal cuts to stratify animals phenotypically on the respective cut weight was demonstrated; the weight of the rump, striploin, and fillet of animals estimated to be in the top 25% genetically for the respective cut, were 10 to 24%, 12 to 24%, and 7 to 17% heavier than the weight of cuts from animals predicted to be in the worst 25% genetically for that cut. Significant exploitable genetic variability in primal carcass cuts was clearly evident even when adjusted to a common carcass weight. The high heritability of many of the primal cuts infers that large datasets are not actually required to achieve high accuracy of selection once the structure of the data and the number of progeny per sire is adequate.


2018 ◽  
Vol 48 (7) ◽  
Author(s):  
Yure Pequeno de Souza ◽  
Paulo Ricardo dos Santos ◽  
Maxwel Rodrigues Nascimento ◽  
Kleyton Danilo da Silva Costa ◽  
Thalyson Vasconcelos Lima ◽  
...  

ABSTRACT: Using genotypes adapted to different regions is one of the main ways to increase Brazilian bean yield. The aim of the present study was to assess the genotypic performance of Carioca beans through mixed models. Fourteen Carioca bean genotypes were assessed in four locations in Pernambuco State (Arcoverde, Caruaru, Belém de São Francisco and São João counties) in 2015. The experiments followed a completely randomized block design, with three repetitions. Genetic parameters were estimated according to the REML/BLUP methodology, whereas genotype selection was based on the harmonic mean of relative performance of genetic values method (MHPRVG). The mean genotype heritability had moderate magnitude, high selective accuracy, besides allowing selection of agronomically superior individuals. Genotypes ‘BRS Notável’, CNFC 15480 and ‘IPR 139’ showed good adaptability and grain yield stability. There was agreement among the statistics μ ̂ + g ̂…, stability (MHVG), adaptability (PRVG), and stability and adaptability of genetic values (MHPRVG) in the discrimination of the most productive genotypes, which presented high adaptability and stability. This outcome indicated that these genotypes can be part of the selection criteria regularly used in bean breeding programs.


2021 ◽  
Vol 22 (10) ◽  
Author(s):  
Zulfahmi Zulfahmi ◽  
Parjanto Parjanto ◽  
Edi Purwanto ◽  
Ahmad Yunus

Abstract. Zulfahmi, Parjanto, Purwanto E, Yunus A. 2021. Genetic diversity and population structure of Eurycoma apiculata in Eastern Sumatra, Indonesia. Biodiversitas 22: 4431-4439. Information on genetic variation within and among populations of Eurycoma apiculata plants is important to develop strategies for their conservation, sustainable use, and genetic improvement. To date, no information on genetic variation within and among populations of the E. apiculata has been reported. This study aims to assess genetic diversity within and among populations of E. apiculata based on RAPD markers, and to determine populations to collect E. apiculata genetic material for conservation and breeding programs. Young leaves of E. apiculata were collected from six natural populations. Fifteen RAPD primers were used to assess the genetic diversity of each population. The data obtained were analyzed with POPGEN and Arlequin software. The amplification results of 15 selected primers produced 3-16 loci with all primers 100% polymorphic. At the species level, the mean allele per locus (Na), number of effective alleles (Ne), percentage of polymorphic loci (PPL), Nei’s gene diversity index (He) and Shannon information index (I) were 2.000, 1.244, 100%, 0.167, and 0.286, respectively. At the population level, the mean values for Na, Ne, PPL, He and I were 1.393, 1.312, 39.27%, 0.119, and 0.186, respectively. The highest value of gene diversity within population (He) was found in the Lingga-1 population and the lowest value was found in the Rumbio population. The value of genetic differentiation among populations (GST) of E. apiculata is 0.284, consistent with the results of the AMOVA analysis which found that genetic variation among populations was 23.14%, indicates that the genetic variation of E. apiculata was more stored within populations than among populations. The gene flow (Nm) value of E. apiculata was 1.259 migrants per generation among populations. The Nm value of this species was high category, and could inhibit genetic differentiation among populations. The clustering of E. apiculata population based on the UPGMA dendrogram and PCA was inconsistent with its geographic distribution, reflecting the possibility that genes migration occurred between islands in the past. The main finding of this study was the genetic variation of the E. apiculata mostly stored within the population. Therefore, the population with the highest genetic diversity is a priority for in-situ conservation, and collection of E. apiculata genetic material for ex-situ conservation and breeding programs should be carried out minimum from Lingga-1 and Pokomo populations.


2009 ◽  
Vol 58 (1-6) ◽  
pp. 79-85 ◽  
Author(s):  
G. H. Huang ◽  
C. L. Zhong ◽  
X. H. Su ◽  
Y. Zhang ◽  
K. Pinyopusarerk ◽  
...  

AbstractCasuarina equisetifolia is an important tree species in tropical/subtropical zones of Asia, the Pacific and Africa. In this study, 220 individuals from seven native provenances and eleven introduced provenances of C. equisetifolia were analyzed to assess the genetic variation and structure using amplified fragment length polymorphism (AFLP) markers. A total of 465 bands were obtained by eight primer pairs, among which 153 were polymorphic. The mean NEI’s gene diversity H = 0.2113 calculated for 18 provenances and the total gene diversity HT = 0.4065 calculated for native provenances suggested abundant variation within provenances and species. High genetic divergence coefficient (GST = 0.4737) and low gene flow (Nm = 0.5555) detected among native provenances suggesting high differentiation of C. equisetifolia. An AMOVA analysis for native provenances revealed a high proportion (46.07%) of the total genetic variation distributed among provenances. The UPGMA clustering (r = 0.8028) and the Mantel test (r = 0.0716) for native provenances showed there was no correlation among genetic relationships and geographical distribution. The genetic information provided important implications for the future conservation and breeding programs of C. equisetifolia.


2022 ◽  
Vol 12 ◽  
Author(s):  
Ahmed Ismael ◽  
Jianming Xue ◽  
Dean Francis Meason ◽  
Jaroslav Klápště ◽  
Marta Gallart ◽  
...  

The selection of drought-tolerant genotypes is globally recognized as an effective strategy to maintain the growth and survival of commercial tree species exposed to future drought periods. New genomic selection tools that reduce the time of progeny trials are required to substitute traditional tree breeding programs. We investigated the genetic variation of water stress tolerance in New Zealand-grown Pinus radiata D. Don using 622 commercially-used genotypes from 63 families. We used quantitative pedigree-based (Genomic Best Linear Unbiased Prediction or ABLUP) and genomic-based (Genomic Best Linear Unbiased Prediction or GBLUP) approaches to examine the heritability estimates associated with water stress tolerance in P. radiata. Tree seedling growth traits, foliar carbon isotope composition (δ13C), and dark-adapted chlorophyll fluorescence (Y) were monitored before, during and after 10 months of water stress. Height growth showed a constant and moderate heritability level, while the heritability estimate for diameter growth and δ13C decreased with water stress. In contrast, chlorophyll fluorescence exhibited low heritability after 5 and 10 months of water stress. The GBLUP approach provided less breeding value accuracy than ABLUP, however, the relative selection efficiency of GBLUP was greater compared with ABLUP selection techniques. Although there was no significant relationship directly between δ13C and Y, the genetic correlations were significant and stronger for GBLUP. The positive genetic correlations between δ13C and tree biomass traits under water stress indicated that intraspecific variation in δ13C was likely driven by differences in the genotype’s photosynthetic capacity. The results show that foliar δ13C can predict P. radiata genotype tolerance to water stress using ABLUP and GBLUP approaches and that such approaches can provide a faster screening and selection of drought-tolerant genotypes for forestry breeding programs.


2021 ◽  
pp. 030157422110116
Author(s):  
Sonam Rastogi ◽  
Manish Goyal ◽  
Mukesh Kumar ◽  
Kalpit Shitalkumar Shaha ◽  
Ekta Yadav ◽  
...  

Objective: To measure and compare bracket transfer accuracy of 3 indirect bonding (IDB) techniques. Material and Methods: Three IDB techniques were studied using polyvinyl siloxane (PVS) putty, vacuum-form (VF), and glue gun (GG). A total of 120 orthodontic stone models were fabricated with die stone, out of which bonding was done on 60 working models and transferred to other 60 patient models. One quadrant was selected for each technique. Digital photography was used to measure the mesiodistal ( X-axis), occlusogingival ( Y-axis), and faciolingual ( Z-axis) position of each bracket on the working and patient models. Results: All the 3 IDB techniques have a very good bracket transfer accuracy. On comparing individual planes, greatest accuracy was seen in GG on X-axis, VF on Y-axis, and VF/PVS on Z-axis. Points A and B were compared for bracket rotation and the mean differences were insignificant indicating that there was no significant amount of rotation in 3 IDB techniques. Conclusions: We can say that all 3 IDB techniques had a very high bracket transfer accuracy. Out of the 3 IDB techniques VF was the most accurate, whereas PVS was the least accurate technique. The selection of technique should be based on tray cost and fabrication time.


1988 ◽  
Vol 59 (01) ◽  
pp. 029-033 ◽  
Author(s):  
K G Chamberlain ◽  
D G Penington

SummaryNormal human platelets have been separated according to density on continuous Percoll gradients and the platelet distribution divided into five fractions containing approximately equal numbers of platelets. The mean volumes and protein contents of the platelets in each fraction were found to correlate positively with density while the protein concentration did not differ significantly between the fractions. Four mitochondrial enzymes (monoamine oxidase, glutamate dehydrogenase, cytochrome oxidase and NADP-dependent isocitrate dehydrogenase) were assayed and their activities per unit volume were found to increase in a very similar monotonie fashion with platelet density. When MAO and GDH were assayed on the same set of density fractions the correlation between the two activities was very high (r = 0.94–1.00, p <0.001) and a similar close correlation was found between MAO and ICDH. The results support the hypothesis that high density platelets either have a higher concentration of mitochondria or have larger mitochondria than low density platelets.


2016 ◽  
Vol 11 (3) ◽  
pp. 217
Author(s):  
Estu Nugroho ◽  
Budi Setyono ◽  
Mochammad Su’eb ◽  
Tri Heru Prihadi

Program pemuliaan ikan mas varietas Punten dilakukan dengan seleksi individu terhadap karakter bobot ikan. Pembentukan populasi dasar untuk kegiatan seleksi dilakukan dengan memijahkan secara massal induk ikan mas yang terdiri atas 20 induk betina dan 21 induk jantan yang dikoleksi dari daerah Punten, Kepanjen (delapan betina dan enam jantan), Kediri (tujuh betina dan 12 jantan), Sragen (27 betina dan 10 jantan), dan Blitar (15 betina dan 11 jantan). Larva umur 10 hari dipelihara selama empat bulan. Selanjutnya dilakukan penjarangan sebesar 50% dan benih dipelihara selama 14 bulan untuk dilakukan seleksi dengan panduan hasil sampling 250 ekor individu setiap populasi. Seleksi terhadap calon induk dilakukan saat umur 18 bulan pada populasi jantan dan betina secara terpisah dengan memilih berdasarkan 10% bobot ikan yang terbaik. Calon induk yang terseleksi kemudian dipelihara hingga matang gonad, kemudian dipilih sebanyak 150 pasang dan dipijahkan secara massal. Didapatkan respons positif dari hasil seleksi berdasarkan bobot ikan, yaitu 49,89 g atau 3,66% (populasi ikan jantan) dan 168,47 g atau 11,43% (populasi ikan betina). Nilai heritabilitas untuk bobot ikan adalah 0,238 (jantan) dan 0,505 (betina).Punten carp breeding programs were carried out by individual selection for body weight trait. The base population for selection activities were conducted by mass breeding of parent consisted of 20 female and 21 male collected from area Punten, eight female and six male (Kepanjen), seven female and 12 male (Kediri), 27 female and 10 male (Sragen), 15 female and 11 male (Blitar). Larvae 10 days old reared for four moths. Then after spacing out 50% of total harvest, the offspring reared for 14 months for selection activity based on the sampling of 250 individual each population. Selection of broodstock candidates performed since 18 months age on male and female populations separately by selecting based on 10% of fish with best body weight. Candidates selected broodstocks were then maintained until mature. In oder to produce the next generation 150 pairs were sets and held for mass spawning. The results revealed that selection response were positive, 49.89 g (3.66%) for male and 168.47 (11.43%) for female. Heritability for body weight is 0.238 (male) and 0.505 (female).


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