Navegando por Autor "Schaffert, Robert Eugene"

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Combining ability of grain sorghum lines selected for aluminum tolerance
(Brazilian Society of Plant Breeding, 2013-12-03) Menezes, Cicero Beserra; Carvalho Júnior, Geraldo Afonso de; Silva, Lidianne Assis; Bernardino, Karine Costa; Souza, Vander Fillipe; Tardin, Flávio Dessaune; Schaffert, Robert Eugene
The purpose of this study was to estimate combining ability of 58 sorghum lines previously selected for Aluminum (Al) toler- ance. One hundred sixty-five hybrids were evaluated at three levels of Al saturation (0%, 20% and 50%) at the same season. General Combining Ability (GCA) effects were significant for female lines for all three traits. GCA effects for male lines were significant only for plant height. Specific Combining Ability (SCA) effects were significant only for flowering time. The ratio GCA to SCA was greater than the unity, indicating the prevalence of additive effects for the control of Al tolerance. F7, F14, F17, F20, F21, F24, F29, F31, F41, F42, F48, F51, F54 and F55 lines contributed to increase yield, while F29, F48 and F51 also contributed to reduce flowering time. M2 was the best male line since it contributed to increase yield and plant height, and to reduce flowering time. Key words: Sorghum bicolor, soil acidity, Aluminum stress, line selection.
Evaluation of grain sorghum hybrids for aluminum tolerance in nutrient solution
(Acta Scientiarum. Agronomy, 2018) Menezes, Cicero Beserra de; Lima, Geisiane Matos; Marucci, Rosangela Cristina; Bernardino, Karine Costa; Santos, Crislene Vieira dos; Júlio, Marcos Paulo Mingote; Schaffert, Robert Eugene
Sorghum (Sorghum bicolor L. Moench) is one of the most important cereal crops in the world. In Brazil, the acreage of grain sorghum during off-season is quite expansive. Most of this area is the Cerrado, a Brazilian biome that is similar to a Savannah and is characterized by high acidity and soluble aluminum at toxic levels for plants. The aluminum acts as a limiting factor in achieving high yields. The purpose of this work was to phenotype sorghum hybrids for aluminum tolerance. Eighteen hybrids were evaluated in a nutrient solution containing {0} or {27} µM Al3+. The work was carried out in a growth chamber at the Embrapa Maize and Sorghum, from April 4 to May 30, 2014. The lines ATF 13B (susceptible) and ATF 14B (tolerant) were used as check cultivars. Based on the Net Root Growth after 120 hours (NRG120), Net Root Growth (NRG168) after 168 hours and Relative Net Root Growth after 168 hours (RNRG168), it was possible to distinguish tolerant hybrids from susceptible ones. The high aluminum saturation reduced root growth by 70%. The hybrids BRS 310 and BRS 373 were tolerant to aluminum stress under nutrient solution. The hybrid BRS 330 was clustered in an intermediate group, with an approximately 50% root growth reduction. The other hybrids were susceptible with significant root reduction.
Evaluation of the potential of lines and hybrids of biomass sorghum
(Industrial Crops and Products, 2018-12-01) Silva, Michele Jorge da; Carneiro, Pedro Crescêncio Souza; Carneiro, José Eustáquio de Souza; Damasceno, Cynthia Maria Borges; Parrella, Nádia Nardely Lacerda Durães; Pastina, Maria Marta; Simeone, Maria Lúcia Ferreira; Schaffert, Robert Eugene; Parrella, Rafael Augusto da Costa
Mutant genotypes of biomass sorghum for low lignin - bmr (brown midrib) and sensitive to photoperiod are interesting for the production of second-generation ethanol. This research aimed to estimate the combining ability between lines A and R of biomass sorghum, both carrying the bmr-6 allele, for bioenergy potential. Three male-sterile lines (A) and ten fertility restorative lines (R) were used, generating 30 hybrids bmr and sensitive to photoperiod. The 30 hybrids, their parents, and six controls were evaluated in a triple lattice design (7 × 7), in two experimental areas of Embrapa Maize and Sorghum, in Sete Lagoas and Nova Porteirinha (Minas Gerais). These lines were crossed in a partial diallel design, based on the Griffing IV model (1956) adapted for partial diallel by Miranda Filho and Geraldi (1984). The evaluated traits were: days to flowering (DTF, days after sowing), plant height (PH, m), fresh biomass yield (FBY, ton.ha−1), dry matter (DM, %), and dry matter yield (DMY, t. ha−1). In addition, the FAI-BLUP selection Index was used to assist the selection of hybrids that simultaneously meet favorable traits. Results revealed that treatments x environment interaction had a significant effect (p < 0.01) for all traits. Moreover, genetic variability was detected between lines A and R, which can be explored by the pyramiding of their favorable alleles, aiming at developing superior hybrids for the production of second-generation bioethanol.
Phenotypic and molecular characterization of sweet sorghum accessions for bioenergy production
(PLoS One, 2017-08-17) Silva, Michele Jorge da; Pastina, Maria Marta; Souza, Vander Fillipe de; Schaffert, Robert Eugene; Carneiro, Pedro Crescêncio Souza; Noda, Roberto Willians; Carneiro, José Eustáquio de Souza; Damasceno, Cynthia Maria Borges; Parrella, Rafael Augusto da Costa
Sweet sorghum [Sorghum bicolor (L.) Moench] is a type of cultivated sorghum characterized by the accumulation of high levels of sugar in the stems and high biomass accumulation, making this crop an important feedstock for bioenergy production. Sweet sorghum breeding programs that focus on bioenergy have two main goals: to improve quantity and quality of sugars in the juicy stem and to increase fresh biomass productivity. Genetic diversity studies are very important for the success of a breeding program, especially in the early stages, where understanding the genetic relationship between accessions is essential to identify superior parents for the development of improved breeding lines. The objectives of this study were: to perform phenotypic and molecular characterization of 100 sweet sorghum accessions from the germplasm bank of the Embrapa Maize and Sorghum breeding program; to examine the relationship between the phenotypic and the molecular diversity matrices; and to infer about the population structure in the sweet sorghum accessions. Morphological and agro-industrial traits related to sugar and biomass production were used for phenotypic characterization, and single nucleotide polymorphisms (SNPs) were used for molecular diversity analysis. Both phenotypic and molecular characterizations revealed the existence of considerable genetic diversity among the 100 sweet sorghum accessions. The correlation between the phenotypic and the molecular diversity matrices was low (0.35), which is in agreement with the inconsistencies observed between the clusters formed by the phenotypic and the molecular diversity analyses. Furthermore, the clusters obtained by the molecular diversity analysis were more consistent with the genealogy and the historic background of the sweet sorghum accessions than the clusters obtained through the phenotypic diversity analysis. The low correlation observed between the molecular and the phenotypic diversity matrices highlights the complementarity between the molecular and the phenotypic characterization to assist a breeding program.
Variabilidade de genótipos de milho quanto à composição de carotenoides nos grãos
(Pesquisa Agropecuária Brasileira, 2009-02) Cardoso, Wilton Soares; Paes, Maria Cristina Dias; Galvão, João Carlos Cardoso; Rios, Sara de Almeida; Guimarães, Paulo Evaristo de Oliveira; Schaffert, Robert Eugene; Borém, Aluízio
O objetivo deste trabalho foi caracterizar e avaliar a variabilidade quanto ao teor e perfil de carotenoides nos grãos de 134 genótipos de milho (Zea mays), com vistas à utilização em programas de biofortificação. Os materiais foram provenientes dos campos experimentais e do Banco Ativo de Germoplasma da Embrapa Milho e Sorgo, Sete Lagoas, MG. São cultivares e híbridos comerciais, linhagens-elite e outros acessos escolhidos com base na coloração amarelo-alaranjada do endosperma. A quantificação do teor de carotenoides totais, carotenos e xantofilas mono-hidroxilada e di-hidroxilada dos grãos foi realizada por método cromatográfico-espectrofotométrico. As médias encontradas nos grãos foram 22,34µ gg-1 de carotenoides totais, 2,55µ gg-1 de carotenos, 3,86µ gg-1 de xantofilas mono-hidroxiladas e 15,93µ gg-1 de xantofilas di-hidroxiladas. Os genótipos foram agrupados em 18 grupos pelo método de Tocher. O germoplasma da Embrapa possui potencial para ser usado em programas de desenvolvimento de linhagens de milho biofortificadas, quanto ao total de carotenoides pró-vitamina A.