Genetic parameters of wheat populations in environments with contrasting temperatures

The objective of this study was to estimate genetic parameters of wheat segregating populations grown in environments with different thermal conditions. Thus, two experiments were carried out at Universidade Federal de Vicosa, Brazil. A 16 by 16 square lattice design was used with two replications, where 240 families from eight segregating populations, 30 families from each population, plus 16 parents were evaluated. In the first experiment, sown in February 2007 (summer), S-0:2 families were evaluated. In the second one, in June 2007 (winter), S-0:3 families were evaluated. Grain yield and thousand grains weight were recorded. So, the most promising population to be grown under different levels of temperature is the Population II originated from BR24/Alianca//EP93541/CPAC9662. It was verified that the thermal conditions might interfere in the wheat genotypes performance and also in the genetic parameters estimates.