The demand for food, fuel, and energy resources continues to increase worldwide. Currently, there are many international efforts aimed at finding renewable, sustainable, and environment friendly solutions for these problems. The spiraling price of petroleum and the adverse effects of using nonrenewable resources are major reasons for increased interest in renewable sources of energy. Brazil, the fifth largest and fifth most populated country in the world, has been developing successful initiatives in renewable sources of energy for more than 75 yr. The production and use of ethanol from sugarcane (Saccharum L.) is a global model for ethanol production, distribution, and use; therefore, the Brazilian ethanol industry has attracted interest from scientists, producers, and governments of both developed and developing countries. Like ethanol, biodiesel is also receiving increased interest in Brazil, with the source material for biodiesel production varying widely between regions. Several oleaginous species have been used, and others are being investigated as potential sources for biodiesel production. Biodiesel was introduced much later than ethanol in Brazil with the formation of the Brazilian Energy Matrix in January 2005 and a mandatory use of at least 2% (B2) biodiesel by 2008 and 5% (B5) by 2013. This paper presents a view of the historic development of ethanol and biodiesel programs in Brazil, emphasizing the strategic role of plant genetic resources as a pillar to support future improvements through plant breeding.

Activities related to genetic resources are characterized by high cost and long term return. Thus the conservation of genetic variability for the future and the efficient utilization of available accessions are two important goals to be attained. However, the low utilization of germplasm banks is not restricted to Brazil but to other developing countries as well. Therefore, pre-breeding is a promising alternative to link genetic resources and breeding programs. Several aspects for maize are discussed such as concept, importance, methods and results. Problems to be investigated and suggestions are also presented.

A escolha do germoplasma é parte fundamental e decisiva para o sucesso de qualquer programa de melhoramento de plantas. Os objetivos deste trabalho foram caracterizar e avaliar o potencial genético de populações crioulas de milho (Zea mays L.) mantidas pelo IAPAR para fins de melhoramento. É apresentada uma caracterização de 25 populações crioulas de milho com relação ao tipo de endosperma e coloração dos grãos. Foram conduzidos ensaios em blocos ao acaso com duas repetições em três locais (Londrina-PR, Ponta Grossa-PR e Anhembi-SP). As populações crioulas mais promissoras para fins de melhoramento com ênfase na produção de grãos, na média dos três locais, foram GI156 (Cayano Sobrália) e GI045 (Tupy Pyta Sopé). A produtividade dessas populações correspondeu, respectivamente, a 86,9% e 84,6% em relação ao híbrido comercial AG122, sendo de mesma magnitude das variedades adaptadas BR-105 e BR-106.

For tropical areas like Brazil, genotype x environment interaction is an important source of variation. Our objectives were to examine the combining abilities and their interaction with environments in ten selected maize (Zea mays L.) inbred lines in diallel crosses and to identify candidates for promising hybrid combinations. Crosses and checks were evaluated through a 7 x 7 triple lattice design at three locations during the 1984/85 season. Several agronomic traits were evaluated, but here only data on ear yield are discussed. Yield data were adjusted for stand variation (correction to 50 plants per plot) and grain moisture (15.5%). Data for ear yield were analysed using an adaptation of Griffing’s method IV for complete diallel crosses, and experiments were repeated in several environments. The means of the crosses over all environments ranged from 6.6 t/ha to 10.3 t/ha. The combining ability analysis of diallel data across environments showed highly significant (P<0.01) effects for environment, general combining ability (GCA), specific combining ability (SCA), and GCA x environment interaction. The SCA x environment interaction was not significant. Results showed that both GCA and SCA were important for this diallel cross. Considering the 13 hybrids that showed higher yields than the commercial hybrid controls, contributions by GCA and SCA effects were 56% and 44%, respectively. On the other hand, selecting only the best five hybrids, SCA effects were always more important than GCA effects for each environment and over all environments.

Abstract