scholarly journals Early selection for resistance to cacao witches’ broom in new parental combinations

2021 ◽  
Vol 47 (2) ◽  
pp. 88-95
Author(s):  
José Luis Pires ◽  
Edna Dora Martins Newman Luz ◽  
Antônio Alves Pimenta Neto
Keyword(s):  
Recurrent Selection ◽  
Early Selection ◽  
Additive Effects ◽  
Dominant Inheritance ◽  
Moniliophthora Perniciosa ◽  
Selection For ◽  
Selection Of ◽  
Better Than

ABSTRACT Progenies from 69 crosses between parents obtained by recurrent selection for resistance and yield were inoculated with Moniliophthora perniciosa basidiospores. The symptoms were evaluated and compared with those in the equally inoculated progenies of Catongo, SIC 23 and SCA 6. Forty-three of the new progenies did not differ statistically from SCA 6, while 10 new progenies were statistically better than this control. The female parents that can be highlighted are (P4B x SCA 6), (MA 16 x SCA 6), (CEPEC 86 x SCA 6), and the EET 75 clone. The best male parents were (CAB 214), (CAB 208) and (P4B x OC 67), which did not differ from each other. This study proved the existence of gene combinations between fathers and mothers, the occurrence of additive effects and the dominant inheritance of these factors, which should allow the selection of clones with higher resistance levels and durability.

scholarly journals Optimum selection intensities in artificial selection programmes: an experimental evaluation

1977 ◽  
Vol 30 (2) ◽  
pp. 115-119 ◽  
Author(s):  
R. Frankham
Keyword(s):  
Experimental Evaluation ◽  
Selection Intensity ◽  
Effective Population ◽  
Term Selection ◽  
Optimum Selection ◽  
Selection For ◽  
Selection Intensities ◽  
Selection Of ◽  
Better Than

SUMMARYAn experimental evaluation of Robertson's (1970) theory concerning optimum intensities of selection for selection of varying durations has been carried out using published results from a long term selection study in Drosophila. Agreement of predicted rankings of treatments with expectations was excellent for low values of t/T (generations/total number scored) but poor for larger values of t/T. This was due to the 20% selection intensity treatments responding worse than expected and the 40% treatments relatively better than expected. Several possible reasons for the discrepancies exist but the most likely explanation is considered to be the greater reduction in effective population size due to selection in treatments with more intense selection.

scholarly journals Parent selection for cocoa resistance to witches'-broom

2010 ◽  
Vol 45 (7) ◽  
pp. 680-685 ◽  
Author(s):  
Stela Dalva Vieira Midlej Silva ◽  
Edna Dora Martins Newman Luz ◽  
José Luis Pires ◽  
Milton Macoto Yamada ◽  
Lindolfo Pereira dos Santos Filho
Keyword(s):  
North Carolina ◽  
Combining Ability ◽  
Recurrent Selection ◽  
General Combining Ability ◽  
Moniliophthora Perniciosa ◽  
Disease Symptoms ◽  
The North ◽  
Parent Selection ◽  
Selection For ◽  
Different Origins

The objective of this work was to identify genotypes with high general combining ability for resistance to witches'-broom (Moniliophthora perniciosa) in populations formed from a first cycle of recurrent selection. Highly productive and resistant clones from different origins were interbred using the North Carolina II design. The clones SCA 6, CSUL 7, RB 39, CEPEC 89, OC 67, BE 4, EEG 29 and ICS 98 were used as paternal parents, while the maternal ones were NA 33, CCN 10, IMC 67, P 4B, CCN 51, CEPEC 86, SGU 54 and ICS 9. Twenty days after germination, 56 seedlings of each cross (four replicates of 14 seedlings) received the inoculation of a 1-mL suspension with 7.5x10(4 ) basidiospores mL-1. Symptoms were evaluated 60 days after inoculation. Significant differences were observed among paternal and among maternal parents, for resistance to witches'-broom assessed according to the proportion of progeny seedlings with the disease symptoms. Differences were also observed between groups of mothers or fathers previously defined as resistant, and groups previously defined as susceptible. It is possible to obtain a combination of genes that can increase the level of resistance to witches'-broom directly from the first cycle of recurrent selection.

Perennial grasses for turf, sport and amenity uses: evolution of form, function and fitness for human benefit

2006 ◽  
Vol 144 (3) ◽  
pp. 189-203 ◽  
Author(s):  
M. D. CASLER
Keyword(s):  
Recurrent Selection ◽  
Perennial Grasses ◽  
12Th Century ◽  
History Of ◽  
Commercial Breeding ◽  
Selection For ◽  
Leisure And Recreation ◽  
Stressful Environments ◽  
Early Human ◽  
Selection Of

The history of genetic modification and improvement of perennial grasses used for turf and sport can be traced back to the earliest events leading to the evolution of traits such as perenniality, asexual reproduction by rhizomes or stolons, apical dominance and hardening or acclimation responses to environmental stress. Human influences on perennial grasses likely began with the dawn of agriculture and the domestication of livestock about 8–10000 years ago with the movement of grasses from forest margins and meadows to pastures and cropland. As agrarian cultures found more time for leisure and recreation, perennial grasses became multi-functional, taking on a greater role with the invention of ball games, sports and a sod industry. Early human selection of superior turf grasses was largely based on individual clones that were vegetatively propagated for commercial purposes, dating back as far as 12th century Japan. The science of turf breeding began in 1962 with the initiation of extensive efforts to collect superior clones from old turf sods in highly stressful environments, followed by numerous cycles of recurrent selection for turf traits in harsh environments and under realistic mowing regimes. These efforts spawned many public and commercial breeding ventures and thousands of cultivars that have spread throughout the world, improving the quality, persistence and functionality of turf for many uses.

scholarly journals Early selection and classification of yerba mate progênies

2018 ◽  
Vol 53 (3) ◽  
pp. 279-286
Author(s):  
Ivar Wendling ◽  
José Alfredo Sturion ◽  
Carlos André Stuepp ◽  
Cristiane Aparecida Fioravante Reis ◽  
Magno Antonio Patto Ramalho ◽  
...  
Keyword(s):  
Mass Production ◽  
Mixed Model ◽  
Early Selection ◽  
Ilex Paraguariensis ◽  
Yerba Mate ◽  
Linear Unbiased Prediction ◽  
Best Linear Unbiased ◽  
Selection For ◽  
Selection Of

Abstract: The objective of this work was to evaluate the feasibility of early selection of open-pollinated yerba mate (Ilex paraguariensis) progenies, and to classify the best parents and candidates for clones. The germplasm is composed of 140 progenies collected from areas within the natural distribution of the species in Southern Brazil and a commercial genotype (control). The experiment was established in Ivaí, in the state of Paraná, Brazil, in March 1997, in randomized complete blocks, with ten replicates, and linear plots of six plants. The commercial mass (kg per plant) of leaves and branches smaller than 7 mm was harvested at 2.5, 4.5, 6.5, and 18.7 years of age. The statistical evaluation was performed using the mixed model procedure with restricted maximum likelihood/best linear unbiased prediction, using the Selegen software. High selective accuracy, significant progeny effects, and genetic variability for commercial mass production were observed for the four harvesting ages. The application of early selection for leaf mass production is feasible for yerba mate progenies harvested at 6.5 years. The selection of the best trees, either for use as parents or as candidates for cloning, provides significant gains for the genetic breeding of yerba mate.

scholarly journals Early selection of Cabralea canjerana for propagation by mini-cutting

2018 ◽  
Vol 53 (9) ◽  
pp. 1018-1024 ◽  
Author(s):  
Cláudia Burin ◽  
Dilson Antônio Bisognin ◽  
Kelen Haygert Lencina ◽  
Eliseo Salvatierra Gimenes
Keyword(s):  
Pearson Correlation ◽  
Early Selection ◽  
Selection Strategy ◽  
Multiplication Rate ◽  
Evaluation Period ◽  
Randomized Design ◽  
Plantlet Growth ◽  
Completely Randomized Design ◽  
Selection For ◽  
Selection Of

Abstract: The objective of this work was to define an early selection strategy to identify Cabralea canjerana (Meliaceae) clones with high multiplication rate. A mini-garden of 109 clones of canjerana seedlings was established in a completely randomized design, in an acclimatized greenhouse. From seedlings, the mini-stumps and mini-cuttings were obtained. Mini-cuttings were collected at five different times, and the number of mini-cuttings per mini-stump, rooting percentage, and number of rooted mini-cuttings were quantified. The number of rooted mini-cuttings per mini-stump was the only trait that showed high correlation with the others. Five groups of clones based on the number of rooted mini-cuttings per mini-stump were separated using k-means clustering, and the genetic gain from selection and Pearson correlation were estimated. The selection of the two best groups in each evaluation period resulted in high genetic gains from selection for all evaluated traits. Early selection for the number of rooted mini-cuttings discarded 65% of the evaluated clones, which increases experimental precision in evaluations of traits associated with plantlet growth and quality. Early selection for the number of rooted mini-cuttings per mini-stump at different times allows the identification of Cabralea canjerana clones with high multiplication rate.

scholarly journals Implications of early selection for resistance to anthracnose in genetic breeding of common bean

2015 ◽  
Vol 15 (3) ◽  
pp. 169-174 ◽  
Author(s):  
José Maria Villela Pádua ◽  
Magno Antonio Patto Ramalho ◽  
Ângela de Fátima Barbosa Abreu
Keyword(s):  
Grain Yield ◽  
Common Bean ◽  
Colletotrichum Lindemuthianum ◽  
Early Selection ◽  
Common Beans ◽  
Selection For ◽  
Pathogen Occurrence ◽  
Efficiency Of Selection ◽  
Segregating Population ◽  
Selection Of

It is questionable if early selection for resistance to Colletotrichum lindemuthianum reduces the efficiency of selection for grain yield in common beans. For this, it was used the segregating population of the cross between two common bean lines: CI107 (susceptible) x BRSMG Madrepérola (resistant). Selection for resistance was carried out in F2and F3, obtaining three types of progenies: not selected (A), selected only in F2(B), and selected in F2and F3(C). The progenies obtained were evaluated for grain yield and pathogen occurrence in experiments. In F3:5, it was used 289 treatments (96 progenies A, 96 B, 95 C and 2 checks (T)); in F3:6, 196 treatments (64 A, 64 B, 64 C and 4 T); in F3:7, 81 treatments (26 A, 26 B, 26 C and 3 T). Selection of plants resistant to anthracnose in early generations increases the successful selection for grain yield in later generations.

scholarly journals Priority based clustering the service providers in federated cloud

2018 ◽  
Vol 7 (2.8) ◽  
pp. 697
Author(s):  
G S Mayuri ◽  
M Saravanan
Keyword(s):  
Service Provider ◽  
Service Providers ◽  
Service Selection ◽  
Cluster Centroid ◽  
User Request ◽  
Cloud Federation ◽  
Selection For ◽  
Cluster 2 ◽  
Selection Of ◽  
Better Than

Cloud is a trending technology now a days. In this technology world now everyone are moving with the cloud. A cloud federation technique is one of the best ways to select any services from the service providers by the user at any time. As large number of service providers in the federation, user need to be select best service provider and the selection of service provider get delayed in the federation. We proposed the cluster based approach to select the best service provider for user request and reducing the selection time of service provider. In previous papers there is no Automated Selection for the selection of best service provider. Our proposed work is based on Automated Selection model i.e., we applied k-means algorithm for grouping the similar services and categorizing the service providers into three groups. Such as Cluster-1, Cluster -2 and Cluster -3, after cluster these cluster sorted in order based on the final centroid of each cluster. Now user request to be compared with the middle cluster centroid and directed to respective cluster for service selection. If more than one service provider offers similar services in the cluster then priority decision tree to be invoked for tie break. This technique works better than existing algorithms and time also to be saved in selection of service.

scholarly journals JUVENILE-MATURE GENETIC CORRELATIONS IN Pinus taeda CLONES PROPAGATED VIA SOMATIC EMBRYOGENESIS

2016 ◽  
Vol 40 (2) ◽  
pp. 255-267
Author(s):  
Poliana Coqueiro Dias ◽  
Aloisio Xavier ◽  
Marcos Deon Vilela de Resende ◽  
Fabrício Antonio Biernaski ◽  
Regiane Abjaud Estopa ◽  
...  
Keyword(s):  
Somatic Embryogenesis ◽  
Pinus Taeda ◽  
Genetic Correlations ◽  
Estimation Procedure ◽  
Early Selection ◽  
Selection Efficiency ◽  
Selection For ◽  
Rotation Age ◽  
High Selection ◽  
Selection Of

ABSTRACT This study aimed to estimate the genetic correlation among selection ages (juvenile - adult) and efficiency of early selection for the height, diameter, and volume traits of individuals from Pinus taeda families propagated via somatic embryogenesis. This study was carried out by genetic-statistical analysis, estimation procedure of variance (Reml), and prediction components of breeding values (Blup), using the Selegen-Reml/Blup software. Genetic correlations among juvenile ages and rotation age were performed by applying the linear model developed by Lambeth (1980). In accordance with results of the established model, the early selection can be performed in clones of Pinus taeda with high selection efficiency. Ages from 4 to 6 years old are enough to select Pinus taeda clones propagated via somatic embryogenesis for harvesting at 8 and 12 years old; and 6 to 10 years old are enough to select them for harvesting at 20 years old. On the basis of the genetic correlations estimates from the environments, the clones' selection of Pinus taeda propagated via somatic embryogenesis should be developed specifically for each environment. The clones' selection can be performed considering the diameter due to the high correlation between volume and diameter.

Lacunar Skull Deformity and Intelligence

PEDIATRICS ◽  
1977 ◽  
Vol 59 (2) ◽  
pp. 296-299
Author(s):  
Marvin A. Fishman ◽  
Helen S. Palkes ◽  
Gary D. Shackelford ◽  
William H. McAlister
Keyword(s):  
Early Treatment ◽  
Good Predictor ◽  
Intellectual Development ◽  
Early Selection ◽  
Prognostic Criteria ◽  
Selection For ◽  
Skull Deformity ◽  
Selection Factors ◽  
Selection Of ◽  
Suggested Modification

Prognostic criteria to be utilized in the selection of neonates with myelomeningoceles for early treatment have been proposed by Lorber.1 Stein et al. suggested modification of the selection factors based on the presence or absence of lacunar skull deformity (LSD) which they thought to be a good predictor of subsequent intellectual development.2 However, disagreement exists regarding the value of LSD as a useful criterion in early selection for treatment because Lonton et al. found only minor differences in intelligence among groups of patients with varying degrees of the deformity.3 In this report, a population of children with myelomeningoceles was studied in an effort to reach definite conclusions regarding the association between LSD and intelligence. See table in the PDF file

scholarly journals Selección de progenitores de maíz para la obtención de semilla híbrida por pequeños agricultores.

2006 ◽  
Vol 11 (2) ◽  
pp. 85 ◽  
Author(s):  
Roberto Valdivia ◽  
Víctor A. Vidal ◽  
Mauro Sierra
Keyword(s):  
Seed Production ◽  
Recurrent Selection ◽  
Winter Season ◽  
Hybrid Seed ◽  
Reciprocal Recurrent Selection ◽  
The Cross ◽  
The Cost ◽  
Selection Of ◽  
Better Than ◽  
Local Farmers

The seed of actual high yielding hybrids are very expensive and local farmers tend to use advanced generations to reduce costs. Abetter choice is to produce seed of maize intervarietal hybrids. The objective of this research was to describe the experience of a group of maize producers in the seed production, utilization and improvement of their parents of intervarietal hybrids. The study was conducted in Nayarit State, Mexico. In 1996, a group farmers, supported by a technical researcher, evaluated two maize intervarietal crosses. The cross B840xC343 yielded better than nine commercial hybrids. This motived the farmers to produce 20 tons of seed in eight intervarietal crosses during the winter season of 1997/98. The cost of the seed production was 50% less than the cost of commercial hybrid seed. The eight intervarietal crosses were commercial planted in about 400 hectars and were evaluated in four experiments by the farmers. The results showed that two crosses, P3028xA7573 and C385xD880, had the best results. The first cross had a heterosis of 4.1% over the high yielding parent and the second a heterosis of 30% over a parent. Since 1999, the parents of the best intervarietal cross is being improved by reciprocal recurrent selection of half siblings, two years per cycle.

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