Correlações entre caracteres agronômicos associados à resistência a tripes em cebola

Genotypic, phenotypic and environmental correlation between agronomic characteristics and Thrips tabaci resistance were determined in 62 half-sibs progenies of onion ValeOuro IPA-11 cultivar. The experiment was conducted under field conditions in Juazeiro, Bahia State, Brazil, with evaluations at 48; 69 and 93 days after transplant (DAT). Commercial bulb yield (PBC) presented genotypic correlation with leaf length (CF) (0,63**); leaf number (NTF) (0,74**); damaged leaf number (NFD) (0,74**); commercial bulb average weight (PMBC) (0,54**); commercial bulb yield (%BC) (0,61**); and non-commercial bulb yield (%BNC) (-0,63**). Genotypic correlations were observed in the number of ninfas of T. tabaci between two fully developed central leaves (NINFA), at 69 DAT and central leaf angle (ANG) (-0,76**); NTF (0,46**); %BC (-0,35**); and yield of unproductive plants (%I) (0,39**). These correlations indicate that lower NINFA numbers occur in plants with lower NTF and higher ANG. Lower NTF plants, on the other hand, have higher ANG (-0,92**). Never thelessNTF correlated positively with PBC, PMBC (0,45**) and %BC (0,43**). Positive genotypic correlations between NFD and PBC, PMBC (0,40**) and %BC (0,51**), imply that this population presents resistance through tolerance.