02114naa a2200193 a 450000100080000000500110000800800410001910000180006024501470007826000090022552015070023465000130174165000100175470000230176470000200178770000190180770000240182677300700185014802372018-06-14       1998    bl uuuu     u00u1 u    #d1 aSANTOS, M. X.  aEvaluation and selection of tropical maize (Zea mays L.) accessions in low-fertility soils with phosphorus limitations.h[electronic resource]  c1998  aExtensive areas in Brazil have severe problems of mineral deficiencies and maize is a genetically diverse cereal species that represents an important option to help maintain the sustainability of agriculture in these areas. The objective of the present study was to characterize and evaluate maize germplasm in low-fertility soil with severe phosphorus (P) limitations and to select promising accessions to be incorporated into breeding programmes. The 269 accessions collected in northeastern Brazil, between 1980 and 1985, were evaluated in two experiments during the 1994/95 season in two locations. Varieties BR 106 and BR 136, selected under conditions of good soil fertility, were added as between-plot checks. The soil was not fertilized and none of the experiments was stressed with drought. The results of combined analysis of variance showed significant differences between treatments (P&lt0.01) and significant accessions x locations interaction in the trials with accessions from different sites, but not in the trials with accessions collected in the same site in the northeastern region. In both locations several accessions were more productive than the best check, indicating that selection in good environments may not be efficient in improving performance in low-fertility environments. The wide range of variation exhibited by the accessions indicates that it is possible to select and utilize genetic resources in less-developed regions in order to maintain sustainable agriculture.  aFósforo  aMilho1 aCARVALHO, H. W. L.1 aLEITE, C. E. P.1 aANDRADE, R. V.1 aVASCONCELLOS, C. A.  tPlant Genetic Resources Newsletter, Romegn. 113, p. 17-21, 1998.