TOLERANCE OF Cedrela fissilis VELL. SEEDLINGS TO DIFFERENT LENGHTS AND INTENSITIES OF FLOODING

A presen\ue7a de \ue1gua no solo, tanto em regime tempor\ue1rio quanto permanente, exige diferentes estrat\ue9gias adaptativas das esp\ue9cies vegetais que ocupam estas \ue1reas. Neste sentido, investigamos as respostas morfol\uf3gicas e de aloca\ue7\ue3o de biomassa em pl\ue2ntulas de Cedrela fissilis Vell. (Meliaceae) submetidas a diferentes amplitudes e intensidades de inunda\ue7\ue3o. Pl\ue2ntulas de Cedrela fissilis foram submetidas a duas intensidades de inunda\ue7\ue3o (submers\ue3o ao n\uedvel de coleto e total) em tr\ueas diferentes amplitudes (cinco, 15 e 20 dias) e ap\uf3s 30, 60 e 90 dias de recupera\ue7\ue3o da condi\ue7\ue3o de inunda\ue7\ue3o foram realizadas avalia\ue7\uf5es da altura da parte a\ue9rea, n\ufamero de folhas, di\ue2metro do colo e \uedndices de clorofila a, b e, total. Ap\uf3s 90 dias de recupera\ue7\ue3o, a altura total, di\ue2metro da raiz, comprimento da raiz, biomassa total, \ue1rea foliar e o crescimento das ra\uedzes foram avaliados. Pl\ue2ntulas n\ue3o inundadas constitu\uedram um grupo controle. As pl\ue2ntulas submetidas \ue0 inunda\ue7\ue3o total n\ue3o sobreviveram. Por outro lado, as pl\ue2ntulas sob inunda\ue7\ue3o parcial recuperaram a taxa de crescimento ao longo dos 90 dias de recupera\ue7\ue3o da inunda\ue7\ue3o. N\ue3o foram observadas diferen\ue7as nas vari\ue1veis de crescimento e aloca\ue7\ue3o de biomassa em rela\ue7\ue3o \ue0s pl\ue2ntulas-controle. Todavia, observou-se que durante o per\uedodo de recupera\ue7\ue3o, as pl\ue2ntulas submetidas a 20 dias de inunda\ue7\ue3o parcial apresentaram maior taxa de abscis\ue3o foliar acompanhado por um aumento nos \uedndices de clorofila a e b. Os resultados indicaram que esta esp\ue9cie apresenta toler\ue2ncia \ue0 intensidade de inunda\ue7\ue3o parcial, devendo ser cuidadosamente selecionada quanto \ue0s \ue1reas de plantio.The presence of water in the soil, in both temporary and permanent regimes, requires different adaptive strategies of plant species that occupy these areas. On this way, we investigated morphological responses of Cedrela fissilis Vell. (Meliaceae) seedlings subjected to different lengths and intensities of flooding. Seedlings of Cedrela fissilis were subjected to two flooding intensity treatments (up to the neck level and total submersion) in three different lengths (five, 15 and 20 days) and we assessed shoot height, numbers of leaf and leaflet, stem diameter and chlorophyll indices a, b and total after 30, 60 and 90 days of recovery from the flood condition. After 90 days of recovery, total height, root diameter, root size, total biomass, leaf area and root growth were evaluated. Non- flooded seedlings constituted a control group. The seedlings subjected to total flooding did not survive. On the other hand, those seedlings under partial flooding restarted growing throughout 90 days of flood recovery. We did not found differences in growth variables and biomass allocation in relation to the control group. However, we observed that plants subjected to 20 days of partial flooding had higher leaf abscission and were accompanied by an increase in the chlorophyll levels. The results indicated that this species shows tolerance to partial flooding and should be carefully selected for planting areas