ROOT AND SHOOT TRAITS OF MAIZE INBRED LINES GROWN IN THE FIELD AND INHYDROPONIC CULTURE AND THEIR RELATIONSHIPS WITH ROOT LODGING

Breeding strategies for improving root lodging resistance in maize (Ze n mays L.) can benefit from the knowledge of the relationships between this and other traits. The objectives of this research were to identi fy two inbred lines that could be used to develop a population to stud y root lodging and to identify associated traits. Eight inbreds were t ested in field trials and in hydroponic culture. Inbred Lo964 far exce eded the others for root lodging resistance showing a much lower root lodging index. The ratio between root pulling resistance and plant hei ght was the only field trait associated with root lodging index (r = - 0.733, P 0.05); the best performance for this ratio was exhibited by L o964 and the worst by Lo1016. The hydroponic traits associated with ro ot lodging index were the development of lateral roots from the radicl e (r = -0.725, P 0.05) and the ratio between the length of the radicle and the length of the shoot at the first leaf collar (r = -0.742, P 0 .05). For these two traits, Lo964 was the best and Lo1016 one of the w orst performing. These two inbreds showed the highest level of dissimi larity based on field and hydroponic traits. Results suggest that Lo96 4 and Lo1016 could be used to develop a population to study root lodgi ng and its association with field and hydroponic traits.