Udenys Cabral Mendes
Abstract:
Recently, the fast expansion of corn cultivation in Brazil due to the opening of new agricultural frontiers (virgin areas and inclusion of degraded pastures) and greater use of the 2nd crop with different climatic conditions, indicates the need to explore new sources of germplasm to meet the wide variability of the environment represented by current and potentially promising areas for culture. Therefore, the wider use of local material (races, varieties, populations, etc.) and the introduction of exotic germplasm with greater or lesser degree of adaptation seems to be a recommended strategy to reach new levels of productivity and adaptability. The aim of this work was to use the partial diallel cross reciprocal crossing scheme to generate information about the potential of two population groups and their heterotic pattern in hybrid combinations for the synthesis of new populations. In the evaluation experiments the parental populations and the intervarietal hybrids obtained from the diallel were used. A randomized block design with four replications was used for evaluation. The following traits were evaluated: grain weight - PG, ear weight - PE, hectoliter weight - Ph, ear length - CE, ear diameter - DE, plant height - AP, ear height - AE, leaf diseases: Exserohilum turcicum - ET, Phaeosphaeria maydis - PM, bedridden plants - PA, broken plants - PQ, male flowering - FM, stem diameter - DC and NRP - number of tassel branches. The best compounds of size k = 2, φ12 ', φ25', φ35 ', φ44', φ55 ', φ65', φ74 ', φ84', φ94 'showed productivity gains of 1, 13, 11, 15, 22 , 13, 14, 17, 12% respectively, in relation to the original NAP populations, with participation of the populations with the highest CGC estimates of the HG group. The populations showed good grain yield and better agronomic pattern in relation to exotic parental populations.
