Genetic parameters and selection of Brachiaria decumbens hybrids for agronomic traits and resistance to spittlebugs
Rogério Gonçalves Mateus, Sanzio Carvalho Lima Barrios, Cacilda Borges do Valle, José Raul Valério, Fabrícia Zimermann Vilela Torres, Lucas Bearari Martins and Pedro Nelson Cesar do Amaral
Abstract – The objective of this work was to estimate genetic parameters for agronomic traits and resistance to spittlebugs in B. decumbens hybrids and to select the ones with best performance. For that, 324 hybrids were evaluated in field plots for agronomic traits and in the greenhouse for resistance to spittlebugs. Genetic variability amongst the hybrids was observed for all traits analyzed. The heritability estimates between genotypes means were higher than 0.52 for all agronomic traits and 0.98 and 0.99 for nymphal survival and nymphal period duration respectively. Hybrids with better performance than cultivar Basilisk for each individual trait were identified and also through a selection index combining all traits. Assigning weights to the different traits in the selection index did not significantly alter the rank for superior hybrids. Those were selected to continue on to the next phases of the breeding program.