Juarez Machado

Dr. Juarez Machado

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 April 2017 in GCB Bioenergy
Verified
Journal Article
Open access
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JRJoão Romero Do Amaral Santos de Carvalho Rocha
João Romero Do Amaral Santos de Carvalho Rocha
JMJuarez Machado
Juarez Machado
PCPedro Crescêncio Souza Carneiro
Pedro Crescêncio Souza Carneiro
This study proposes a new multitrait index based on factor analysis and ideotype‐design (FAI‐BLUP index), and validates its potential on the selection of elephant grass genotypes for energy cogeneration. Factor analysis was carried out, and afterwards, factorial scores of each ideotype were designed according to the desirable and undesirable factors, and the spatial probability was estimated based on genotype‐ideotype distance, enabling genotype ranking. In order to quantify the potential of the FAI‐BLUP index, genetic gains were predicted and compared with the Smith‐Hazel classical index. The FAI‐BLUP index allows ranking the genotypes based on multitrait, free from multicollinearity, and it does not require assigning weights, as in the case of the Smith‐Hazel classical index and its derived indices. Furthermore, the genetic correlation ‐ positive or negative ‐ within each factor was taken into account, preserving their traits relationship, and giving biological meaning to the ideotypes. The FAI‐BLUP index indicated the 15 elephant grass with the highest performance for conversion to bioenergy via combustion, and predicted balanced and desirable genetic gains for all traits. In addition, the FAI‐BLUP index predicted gains of approximately 62% of direct selection, simultaneously for all traits that are desired to be increased, and approximately 33% for traits which are desired to be decreased. The genotypes selected by the FAI‐BLUP index have potential to improve all traits simultaneously, while the Smith‐Hazel classical index predicted gains of 66% for traits that are desired to be increased, and −32% for traits that are desired to be decreased, and it does not have potential to improve all traits simultaneously. The FAI‐BLUP index provides an undoubtable selection process and can be used in any breeding programme aiming at selection based on multitrait.

1 March 2017 in Crop Breeding and Applied Biotechnology
Verified
Journal Article
Open access
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APAntônio Vander Pereira
Antônio Vander Pereira
BLBrazil Embrapa Gado de Leite
Brazil Embrapa Gado de Leite
FLFrancisco José da Silva Lédo
Francisco José da Silva Lédo
JMJuarez Machado
Juarez Machado
Cultivar BRS Kurumi is characterized by short plant height, short internodes, high dry matter production (29.25 t ha-1yr-1), has a high nutritional value and is recommended for the cut-and-carry system or grazing. Cultivar BRS Capiaçu, indicated for silage and the cut-and-carry system, has tall upright growth, high dry matter production (49.75 t ha-1yr-1), good forage quality, is lodging-resistant and suitable for mechanical harvesting. Both cultivars are vegetatively propagated by stem cuttings.

30 April 2021 in Frontiers in Plant Science
Verified
Journal Article
Open access
RSRosangela M. Simeão
Rosangela M. Simeão
MRMarcos D. V. Resende
Marcos D. V. Resende
RARodrigo S. Alves
Rodrigo S. Alves
MPMarco Pessoa-Filho
Marco Pessoa-Filho
AAAna Luisa S. Azevedo
Ana Luisa S. Azevedo
JMJuarez Machado
Juarez Machado
The world population is expected to be larger and wealthier over the next few decades and will require more animal products, such as milk and beef. Tropical regions have great potential to meet this growing global demand, where pasturelands play a major role in supporting increased animal production. Better forage is required in consonance with improved sustainability as the planted area should not increase and larger areas cultivated with one or a few forage species should be avoided. Although, conventional tropical forage breeding has successfully released well-adapted and high-yielding cultivars over the last few decades, genetic gains from these programs have been low in view of the growing food demand worldwide. To guarantee their future impact on livestock production, breeding programs should leverage genotyping, phenotyping, and envirotyping strategies to increase genetic gains. Genomic selection (GS) and genome-wide association studies play a primary role in this process, with the advantage of increasing genetic gain due to greater selection accuracy, reduced cycle time, and increased number of individuals that can be evaluated. This strategy provides solutions to bottlenecks faced by conventional breeding methods, including long breeding cycles and difficulties to evaluate complex traits. Initial results from implementing GS in tropical forage grasses (TFGs) are promising with notable improvements over phenotypic selection alone. However, the practical impact of GS in TFG breeding programs remains unclear. The development of appropriately sized training populations is essential for the evaluation and validation of selection markers based on estimated breeding values. Large panels of single-nucleotide polymorphism markers in different tropical forage species are required for multiple application targets at a reduced cost. In this context, this review highlights the current challenges, achievements, availability, and development of genomic resources and statistical methods for the implementation of GS in TFGs. Additionally, the prediction accuracies from recent experiments and the potential to harness diversity from genebanks are discussed. Although, GS in TFGs is still incipient, the advances in genomic tools and statistical models will speed up its implementation in the foreseeable future. All TFG breeding programs should be prepared for these changes.

1 July 2012 in Crop Science
Verified
Journal Article
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AAAna Luisa Sousa Azevedo
Ana Luisa Sousa Azevedo
PCPricila Palla Costa
Pricila Palla Costa
JMJuarez Machado
Juarez Machado
MMMarco Antonio Machado
Marco Antonio Machado
APAntônio Vander Pereira
Antônio Vander Pereira
FLFrancisco José da Silva Lédo
Francisco José da Silva Lédo
Napier grass (Pennisetum purpureum Schum.) is an important forage crop in tropical areas although little is known about its genome information, and few molecular markers have been developed for this species. This work aimed to check the viability of cross‐species amplification of microsatellite markers between pearl millet (Pennisetum glaucum) and Napier grass and to evaluate the genetic diversity among Napier grass germplasm accessions. Fifty‐four microsatellite markers previously described in pearl millet were tested against Napier grass, and 30 markers (55.5%) showed successful cross‐amplification. From them, 18 microsatellite markers were selected to study the genetic diversity in the Embrapa Active Germplasm Bank of Napier Grass (Embrapa‐BAGCE). A total of 180 alleles were identified by these selected microsatellite markers in 107 Napier grass accessions and four pearl millet samples. The average similarity coefficient (Dice) calculated among the Embrapa‐BAGCE accessions was 0.651, ranging from 0.254 to 1.0. Some accessions showed similarity coefficients equal to one, indicating that they have common progenitors or that they might be the same accessions with different denomination. To our knowledge, this work is the first to describe microsatellite markers in Napier grass and represents a significant advance regarding the use of molecular markers in this species.

1 January 2017 in Industrial Crops and Products
Verified
Journal Article
Open access
JRJoão Romero Do Amaral Santos de Carvalho Rocha
João Romero Do Amaral Santos de Carvalho Rocha
JMJuarez Machado
Juarez Machado
PCPedro Crescêncio Souza Carneiro
Pedro Crescêncio Souza Carneiro
JCJailton da Costa Carneiro
Jailton da Costa Carneiro
MRMarcos Deon Vilela Resende
Marcos Deon Vilela Resende
JCJosé Eustáquio de Souza Carneiro
José Eustáquio de Souza Carneiro

1 January 2017 in Industrial Crops and Products
Verified
Journal Article
Closed access
JRJoão Romero Do Amaral Santos de Carvalho Rocha
João Romero Do Amaral Santos de Carvalho Rocha
JMJuarez Machado
Juarez Machado
PCPedro Crescêncio Souza Carneiro
Pedro Crescêncio Souza Carneiro
JCJailton da Costa Carneiro
Jailton da Costa Carneiro
MRMarcos Deon Vilela Resende
Marcos Deon Vilela Resende
JCJosé Eustáquio de Souza Carneiro
José Eustáquio de Souza Carneiro