Pedro Mário de Araújo

Análise de fatores e regressão bissegmentada em estudos de estratificação ambiental e adaptabilidade em milho

The objective of this work was to verify possible divergences among results obtained on adaptability evaluations of 27 maize genotypes (Zea mays L.), and on stratification of 22 environments on Parana State, Brazil, through techniques of factor analysis and bissegmented regression. The environmental stratifications were made through the traditional methodology and by factor analysis, allied to the percentage of the simple portion of GxE interaction (PS%). Adaptability analyses were carried out through bissegmented regression and factor analysis. By the analysis of bissegmented regression, studied genotypes had presented high productive performance; however, it was not evidenced the genotype considered as ideal. The adaptability of the genotypes, analyzed through graphs, presented different answers when compared to bissegmented regression. Factor analysis was efficient in the processes of environment stratification and adaptability of maize genotypes.

Plant breeding at Instituto Agronômico do Paraná: IAPAR

The plant breeding program at IAPAR started in 1972, soon after its foundation, and has as main objective the development of superior cultivars with high yield potential, genetic resistance to major biotic and abiotic adverse factors and good nutritional and technological quality. Over these forty years, IAPAR has made available to farmers 184 cultivars of different species, resulting in an increase in the productivity, greater availability of food, decrease in environmental impacts, addition of value to agricultural properties and life improvement of farmers and consumers. Thus, the institution fulfills its mission of generating technology, contributing to the development of agriculture in Parana and in other parts of Brazil, since many of the cultivars developed are used in different regions of the country.

Predicting rapeseed oil content with near‑infrared spectroscopy

The objective of this work was to establish a calibration equation and to estimate the efficiency of near-infrared reflectance (NIR) spectroscopy for evaluating rapeseed oil content in Southern Brazil. Spectral data from 124 half-sib families were correlated with oil contents determined by the chemical method. The accuracy of the equation was verified by coefficient of determination (R2) of 0.92, error of calibration (SEC) of 0.78, and error of performance (SEP) of 1.22. The oil content of ten genotypes, which were not included in the calibration with NIR, was similar to the one obtained by the standard chemical method. NIR spectroscopy is adequate to differentiate oil content of rapeseed genotypes.