scholarly journals Selection of coffee progenies for resistance to nematode Meloidogyne paranaensis in infested area

2014 ◽  
Vol 14 (2) ◽  
pp. 94-101 ◽  
Author(s):  
Sonia Maria Lima Salgado ◽  
Juliana Costa de Rezende ◽  
José Airton Rodrigues Nunes
Keyword(s):  
Genetic Variability ◽  
Coffea Arabica ◽  
Mixed Model ◽  
High Rate ◽  
Germplasm Bank ◽  
Genotypic Association ◽  
Coffee Plants ◽  
Plagiotropic Branches ◽  
Mixed Model Methodology ◽  
Selection Of

The purpose of this study was to select Coffea arabica progenies for resistance to M. paranaensis in an infested coffee growing area using Henderson's mixed model methodology. Forty-one genotypes were selected at the Coffee Active Germplasm Bank of Minas Gerais, and evaluated in regard to stem diameter, number of plagiotropic branches, reaction to the nematode, and yield per plant. There was genetic variability among the genotypes studied for all the traits evaluated, and among the populations studied for yield and reaction to the nematode, indicating possibilities for obtaining genetic gains through selection in this population. There was high rate of genotypic association between all the traits studied. Coffee plants of Timor Hybrid UFV408-01 population, and F3 progenies derived from crossing Catuaí Vermelho and Amphillo MR 2161 were the most promising in the area infested by M. paranaensis.

scholarly journals Plant selection in F2 segregating populations of papaya from commercial hybrids

2012 ◽  
Vol 12 (3) ◽  
pp. 191-198 ◽  
Author(s):  
Eder Jorge Oliveira ◽  
Gilberto de Andrade Fraife Filho ◽  
Juan Paulo Xavier de Freitas ◽  
Jorge Luiz Loyola Dantas ◽  
Marcos Deon Vilela de Resende
Keyword(s):  
Genetic Parameters ◽  
Mixed Model ◽  
Soluble Solids ◽  
Fruit Firmness ◽  
Plant Selection ◽  
F2 Population ◽  
The Common ◽  
Mixed Model Methodology ◽  
Fruit Diameter ◽  
Selection Of

The objective of this paper was to estimate the genetic parameters and additive genetic values in segregating populations of papaya using the mixed model methodology. Two F2 populations from Tainung and Calimosa hybrids were evaluated. The experimental design was an augmented block with four replicates, and Golden and Calimosa cultivars were the common treatment. Estimates of individual heritability were high for fruit length (FL) and weight (FW), moderate for fruit diameter (FD), and low for total soluble solids (TSS) and fruit firmness (FF). Considering FF and TSS as main traits for selection, genotypes of Calimosa-F2 population showed better performance to FF, but worse concerning TSS. It was selected 18.3% and 24.6% of plants from Tainung-F2 and Calimosa-F2 populations, respectively. Negative correlation between TSS and FF was not able to reduce the genetic gains. The segregating populations from Calimosa hybrid are more promising for the selection of papaya lines.

scholarly journals Selection of alfalfa cultivars adapted for tropical environments with repeated measures using PROC MIXED of SAS® System

2009 ◽  
Vol 8 (1) ◽  
pp. 55-62 ◽  
Author(s):  
G. M. L. de Assis ◽  
A. C. Ruggieri ◽  
M. E. Z. Mercadante ◽  
G. M. F. de Camargo ◽  
J. M. Carneiro Júnior
Keyword(s):  
Genetic Variability ◽  
Repeated Measures ◽  
Management Practices ◽  
Mixed Model ◽  
Animal Feed ◽  
Tropical Regions ◽  
Tropical Environments ◽  
Best Linear Unbiased ◽  
Adequate Management ◽  
Selection Of

Although alfalfa (Medicago sativa L.) is a leguminous herbage widely used in temperate regions as animal feed, there is not much research in tropical regions to develop cultivars adapted to these environmental conditions. The utilization of adapted cultivars with adequate management practices is important to improve productivity, quality and persistence of cultivated pastures. The objectives of this study were to verify the genetic variability among alfalfa cultivars and to rank them using mixed model methodology. A total of 35 alfalfa cultivars were evaluated in the rainy and dry seasons, from 1996 to 2000, in plots of 2.8 m2 in Sertãozinho, São Paulo, Brazil. The experimental design was a randomized complete block with three replications. Longitudinal data of dry matter yield were analyzed using PROC MIXED of SAS® System. Several covariance structures were tested and the spherical spatial structure was selected. The results show that the genetic variability was statistically significant only for the dry season. Moreover, the interaction among cultivars and harvests variance was highly significant for both seasons. The empirical best linear unbiased predictions of cultivar effects were obtained, allowing for the selection of the superior cultivars MH 15, 5715, SW 8210, Rio, High, 5888, Monarca, Victoria, Florida 77 and Falcon. Crioula, the most common cultivar in Brazil, showed low forage potential in Sertãozinho. Results indicate potential for use of more productive cultivars of alfalfa to produce animal feed in tropical environments.

Stimuli increasing oviposition by female coffee white stem borer (Coleoptera: Cerambycidae)

2001 ◽  
Vol 133 (3) ◽  
pp. 409-412 ◽  
Author(s):  
Marc Rhainds ◽  
Maarten Warndorff ◽  
Phang Kok Chiew ◽  
Chin Chiew Lan ◽  
Gerhard Gries
Keyword(s):  
South Africa ◽  
Coffea Arabica ◽  
Stem Borer ◽  
Fruit Production ◽  
Major Pest ◽  
Coffee Plants ◽  
Oviposition Sites ◽  
Control Management ◽  
Selection Of ◽  
Extensive Damage

The coffee white stem borer, Xylotrechus quadripes (Chevrolat) is a major pest of coffee, Coffea arabica (L.) (Rubiaceae), in South Africa, India, Thailand, and China (Duffy 1968; Schoeman 1990; Visitpanich 1994; Montavon 1997). Females lay eggs singly or in batches, generally under bark crevices of the stem. Neonatal larvae feed beneath the bark and, during development, bore deeply inside the stem. Stems are colonized by up to 60 larvae. Extensive damage by larvae causes mortality of coffee plants or reduction of fruit production (Duffy 1968; GK veeresh). Because larvae inside the stems of coffee plants are difficult to control, management tactics are aimed at preventing infestation, either by interfering with oviposition of females or by killing neonates before they bore into the stem. Our study tested insect and host plant derived stimuli that may affect the selection of oviposition sites by female X. quadripes.

scholarly journals Caffeine content of Ethiopian Coffea arabica beans

2000 ◽  
Vol 23 (1) ◽  
pp. 213-215 ◽  
Author(s):  
Maria Bernadete Silvarolla ◽  
Paulo Mazzafera ◽  
Marinez Muraro Alves de Lima
Keyword(s):  
Genetic Diversity ◽  
Coffea Arabica ◽  
Breeding Program ◽  
Germplasm Bank ◽  
Caffeine Content ◽  
Coffee Plants

The coffee germplasm bank of the Instituto Agronômico de Campinas has many Coffea arabica accessions from Ethiopia, which is considered the primary center of genetic diversity in coffee plants. An evaluation of the caffeine content of beans from 99 progenies revealed intra- and inter-progeny variability. In 68 progenies from the Kaffa region we found caffeine values in the range 0.46-2.82% (mean 1.18%), and in 22 progenies from Illubabor region these values ranged from 0.42 to 2.90% (mean 1.10%). This variability could be exploited in a breeding program aimed at producing beans with low-caffeine content.

Discovery of five new Galactic symbiotic stars in the VPHAS+ survey

2021 ◽  
Vol 502 (2) ◽  
pp. 2513-2517
Author(s):  
Stavros Akras ◽  
Denise R Gonçalves ◽  
Alvaro Alvarez-Candal ◽  
Claudio B Pereira
Keyword(s):  
Spectroscopic Data ◽  
Selection Criterion ◽  
Optical Spectra ◽  
Emission Lines ◽  
High Rate ◽  
Symbiotic Stars ◽  
Selection Of

ABSTRACT We report the validation of a recently proposed infrared (IR) selection criterion for symbiotic stars (SySts). Spectroscopic data were obtained for seven candidates, selected from the SySt candidates of Akras et al. by employing the new supplementary IR selection criterion for SySts in the VST/OmegaCAM Photometric H-Alpha Survey. Five of them turned out to be genuine SySts after the detection of H α, He ii, and [O iii] emission lines as well as TiO molecular bands. The characteristic O vi Raman-scattered line is also detected in one of these SySts. According to their IR colours and optical spectra, all five newly discovered SySts are classified as S-type. The high rate of true SySts detections of this work demonstrates that the combination of the H α emission and the new IR criterion improves the selection of target lists for follow-up observations by minimizing the number of contaminants and optimizing the observing time.

scholarly journals Joint analysis of phenotypic and molecular diversity provides new insights on the genetic variability of the brazilian physic nut germplasm bank

2013 ◽  
Vol 36 (3) ◽  
pp. 371-381 ◽  
Author(s):  
Alexandre Alonso Alves ◽  
Leonardo Lopes Bhering ◽  
Tatiana Barbosa Rosado ◽  
Bruno Galvêas Laviola ◽  
Eduardo Fernandes Formighieri ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Molecular Diversity ◽  
Joint Analysis ◽  
Physic Nut ◽  
Germplasm Bank

scholarly journals Influence of coffee pruning on the severity of frost damage

2000 ◽  
Vol 43 (1) ◽  
Author(s):  
Armando Androcioli Filho ◽  
Paulo Henrique Caramori
Keyword(s):  
Field Experiment ◽  
Coffea Arabica ◽  
Frost Damage ◽  
W State ◽  
Southern Brazil ◽  
Frost Risk ◽  
Plagiotropic Branches

Frost damages in a field experiment of pruning types and systems for the cultivars of Coffea arabica Catuaí and Mundo Novo, were evaluated at Londrina (23º22’S, 52º10´W), State of Parana, southern Brazil, during the winter of 1990 and 1994. Pruning types evaluated were ‘esqueletamento’ (cutting off all plagiotropic branches at 20-30 cm from the orthotropic branch), ‘decote’ (cutting off the orthotropic branch at 1.5 m and 2.0 m above ground) and ‘recepa’ (cutting off the orthotropic branch at 0.8 m above ground), performed on all rows and on alternate rows, and on different sections of the plant. Results indicated that frost damage could increase according to the type and height of pruning. The pruning type ‘esqueletamento’ and prunings at higher levels were more suitable for regions with frost risk. Under severe frost condition, pruning type did not affect the damage in anyone of the treatments evaluated.

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