Ricardo Augusto de Oliveira

Genetic improvement of sugar cane for bioenergy: the brazilian experience in network research with RIDESA

In this paper, it is presented RIDESAs model for sugar cane breeding to ethanol, and its scientific, technological and human resources training contributions. RIDESA is an inter-university network for the development of sugar cane industry in Brazil, and was formed by a technical cooperation agreement between ten public universities. The model of network management is presented in this study, which involves, among other things, the public-private partnership (Universities-Mills) for the development of cultivars. RIDESA has produced 59 cultivars since 1990 and is now responsible for 59% of the total area cultivated with this plant in Brazil. In the last five years, 286 agronomists were trained in breeding programs at universities that comprise RIDESA. In this same period, the network formed 35 professors, 24 doctors and 7 post-docs in researches with this crop. It is also presented a conceptual approach on methods of sugar cane breeding involving families and genome-wide selection.

Adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais

The objective of this research was to evaluate the adaptability and phenotypic stability of genotypes of sugarcane in the state of Minas Gerais, Brazil. There had been evaluated 15 genotypes in nine environments. The experiments were conducted in a randomized block design with three replications. To discriminate the genotypes the variable TPH (tons of pol per hectare) was used. These values corresponded to the average of two cuts. The results showed that the check RB867515 presented greater general adaptability and phenotypic stability, followed by genotype RB987935, which had the highest average and high general and specific adaptability to favorable and unfavorable environments that may be suitable for commercial cultivation.

Evaluation of sugarcane genotypes and production environments in Paraná by GGE biplot and AMMI analysis

The purpose of this study was to evaluate sugarcane genotypes for the trait tons of sugar per hectare (TSH), stratifying five production environments in the state of Parana. The performance of 20 genotypes and 2 standard cultivars was analyzed in three consecutive growing seasons by the statistical methods AMMI and GGE Biplot. The GGE Biplot grouped the locations into two mega-environments and indicated the best-performing genotypes for each one, facilitating the selection of superior genotypes. Another advantage of GGEBiplot is the definition of an ideal genotype (G) and environment (E), serving as reference for the evaluation of genotypes and choice of environments with greater GE interaction. Both models indicated RB006970, RB855156 and RB855453 as the genotypes with highest TSH and Sao Pedro do Ivai as the environment with the greatest GE interaction. Both approaches explained a high percentage of the sum of squares, with a slight advantage of AMMI over GGE Biplot analysis.

Procedimento Blupis e seleção massal em cana-de-açúcar

O objetivo deste trabalho foi comparar a selecao via procedimento BLUP individual simulado (BLUPIS) versus selecao massal em familias de irmaos-completos de cana-de-acucar. Foram utilizadas 80 familias originadas de cruzamentos biparentais da serie RB03. O experimento foi desenvolvido em area experimental, localizado no Municipio de Sao Tome, Parana. O delineamento experimental foi em blocos incompletos, com cinco repeticoes por familia. Para selecao considerou-se a variavel tonelada de solidos soluveis por hectare (TSH). Utilizou-se o modelo 35 do programa computacional Selegen REML/BLUP, via procedimento BLUPIS para a indicacao do numero de clones potenciais a serem selecionados. Estes resultados foram correlacionados com o numero de clones selecionados via selecao massal dentro das familias. A selecao clonal via procedimento BLUPIS indica maior numero de clones promissores para caracteres quantitativos dentro de familias com elevados efeitos genotipicos.

Forage productivity and morphogenesis of Axonopus aureus under different nitrogen fertilization rates

) on forage yield and morphogenesis of Axonopus aureus was evaluated in the savannas of Roraima State, Brazil. The experimental design was in randomized blocks with three replicates. The grass showed high responsiveness to N fertilization. Dry weight (DW) yield, morphogenetic and structural traits and forage quality were positively affected by N fertilization. The effects of N fertilization on DW yield, N content, leaf appearance rate, leaf elongation rate, number of live leaves/tiller, final leaf length and leaf area index were quadratic and maximum values were estimated with application of 168.8 (2,181 kg ha -1 ); 124.8 (21.1 g/kg); 158.5 (0.163 leaf/day per tiller); 172.3 (2.75 cm/tiller per day); 155.5 (17.23 cm); 185.5 (7.55 leaves/tiller) and 185.3 (2.22) kg N ha -1 , respectively. Tiller population density and leaf senescence rate are directly proportional to increase in N rates, and the opposite occurs for N utilization efficiency and apparent N recovery.

Produtividade de Forragem e Morfogênese de Trachypogon plumosus sob Diferentes Níveis de Desfolhação

O efeito de niveis de desfolhacao (5, 10, 15, 20, 25 e 30 cm acima do solo) sobre a producao de forragem e caracteristicas morfogenicas e estruturais de Trachypogon plumosus foi avaliado nos cerrados de Roraima. Os efeitos dos niveis de desfolhacao sobre a producao de materia seca, numero de folhas/perfilho, tamanho medio de folhas, area foliar e taxas de aparecimento e expansao de folhas foram quadraticos e os maximos valores registrados com cortes a 22,3; 19,7; 25,9; 23,4; 21,5 e 22,4 cm acima do solo, respectivamente. A densidade populacional de perfilhos foi diretamente proporcional ao nivel de desfolhacao, ocorrendo o inverso quanto a taxa de senescencia foliar. A eliminacao de meristemas apicais foi incrementada com o aumento do nivel de desfolhacao. O vigor de rebrota foi direta e negativamente correlacionado com o nivel de desfolhacao. DOI: 10.15528/2176-4158/rcpa.v14n2p169-172

RB966928: Early maturing sugarcane cultivar

RB966928 is an early to medium maturing sugarcane cultivar and in Central-Southern Brazil it is harvested between April and June; it is recommended for planting in environments with medium to high soil fertility. It stands out with a high ratoon yield and with excellent sprouting in both plant cane and ratoon cane. It is tolerant to the major diseases of economic importance of sugarcane.

NIR SPECTROSCOPIC MODELS FOR PHENOTYPING WOOD TRAITS IN BREEDING PROGRAMS OF Eucalyptus benthamii

A caracterizacao da madeira deve ser feita em grandes populacoes dos programas de melhoramento de eucaliptos, a fim de selecionar eficientemente arvores potenciais. Neste estudo, a madeira de E. benthamii foi caracterizada de forma nao destrutiva e avaliou-se o desempenho da espectroscopia de infravermelho proximo (NIR) na estimativa da densidade basica da madeira, lignina, extrativos, glicose, xilanas e carboidratos totais. Modelos NIR para caracteristicas da madeira foram realizados a partir de 481 arvores do teste de progenie de E. benthamii (4 anos de idade) destinada a producao de celulose no estado de Santa Catarina, no sul do Brasil. Baguetas foram amostrados para caracterizacao quimica e fisica em laboratorio, bem como para analises de espectroscopia NIR. 350 amostras foram selecionadas via PCA para calibracoes de modelos, enquanto 131 foram reservadas para o teste de validacao independente. A madeira de E. benthamii apresentou os padroes exigidos para processo de polpa Kraft. Os modelos preditivos NIR apresentaram capacidade satisfatoria para estimar as propriedades quimicas da madeira. Os modelos de predicao para teores totais de lignina, extrativos, xilanas e carboidratos totais apresentaram coeficientes de determinacao de 0,53, 0,65, 0,36 e 0,53, com valores de RPD variando de 1,3 a 2,3. O modelo preditivo para a densidade basica da madeira e glicose apresentaram baixo coeficiente de determinacao (0,13 e 0,10). No entanto, nao e possivel usar esses ultimos modelos para classificacao e selecao genetica porque nao houve correlacao. Porem, o modelo para extrativos apresentou boa qualidade e pode ser usado para predicao e melhoramento genetico. Portanto, a espectroscopia NIR tem potencial para ser aplicada em programas de melhoramento, pois permite uma selecao precoce e nao destrutiva de arvores para propriedades quimicas do processo de producao de celulose.

Ajuste de modelos de produção água-cultura para cana-soca

Sugarcane (Saccharum spp.) is one of the main products in the Brazilian agribusiness. In the Paraná State, sugarcane occupies an area of 665,000 ha, with an annual production of about 50 million tons. The Paranavaí region accounts for 20 % of this production, and the planted area is increasing fast in this region (Paraná 2015). Agriculture is the economic activity that has a higher dependence on weather conditions, which are responsible for the oscillations of agricultural seasons (Souza 2014). Environmental factors directly affect plant growth and development. However, the relations between climatic parameters and agricultural production are quite complex. The influence of climate on sugarcane is remarkable because it is a semiperennial crop, grown under different environmental conditions, causing production variations over the years (Silva et al. 2008). ABSTRACT RESUMO

Características morfogênicas e estruturais de Trachypogon plumosus de acordo com a fertilidade do solo e o nível de desfolha

The objective of this work was to evaluate the effects of growing seasons, liming, fertilization, and defoliation levels on morphogenetic and structural traits of Trachypogon plumosus in the savanna of the state of Roraima, Brazil. The following treatments were evaluated: correction of soil fertility (control, liming, fertilization, and liming + fertilization), defoliation levels (removal of 50 and 75% of the leaves), and growing seasons (rainy and dry). The grass positively responded to the correction of soil fertility. Fertilization and liming + fertilization, during the rainy season, provided higher leaf appearance rates (LApR), leaf elongation rates, number of live leaves (NLL), leaf lifespan, final leaf length (FLL), leaf area index (LAI), and tiller population density (TPD), besides a lower phyllochron. The evaluated variables were significantly reduced during the dry season, except for leaf senescence rate. The lowest defoliation level positively affected LApR, FLL, and LAI, but not NLL and TPD. The management with lower defoliation level maximizes the harnessing of environmental resources and forage use efficiency.