AVALIAÇÃO DE LINHAGENS S3 DE MILHO POR MEIO DE TESTADORES ADAPTADOS À SAFRINHA

Abstract

Several breeding programs aim to develop superior maize genotypes able to be explored in off-season cropping, mainly due to the increased area under maize produced in alternative season. Few hybrids on the market are adapted to the environmental conditions of autumn-winter. The objective of this study was to identify the inbred lines adapted to off-season condition, by the analysis of combining ability of 50 S3 maize inbred lines, developed by the Maringá State University. These inbred lines were crossed with two adapted hybrids (AG9040 and P30K75), used as testers. The male and female flowering time and also the grain yield (kg ha-1) adjusted for moisture (14,5%) and stand (65.000 plants) were evaluated in 3 locations of the western region of Paraná. The tester AG9040 presents itself as the best to contribute to high grain yields in their topcrosses. The line 30 had high general combining ability for yield in the three environments. The crossing line AG9040 x 49 obtained significant estimates of specific combining ability (SCA) for grain yield in Toledo and Palotina. Also, there is the crossing line AG9040 x 38 to obtain relevant SCA for yield and flowering Tupãssi in male and female. With the tester 30K75 mainly determined by the intersection with the line 27, so it is recommended that this inbred line can be used as tester lines from the commercial hybrid 30K75. With the tester AG9040 mainly determined by the intersection with the line 48, therefore, thes lines can be used as a new tester inbred lines derived from commercial hybrid AG9040.