Influence of copper soil contamination on growth and quality of acoita-cavalo ( Luehea divaricata Mart. & Zucc.) and aroeira-vermelha ( Schinus therebinthifolius Raddi) seedlings

A contamina\ue7\ue3o do solo por cobre tem se tornado comum em \ue1reas de minera\ue7\ue3o e de viticultura no Rio Grande do Sul. O trabalho objetivou avaliar o efeito de doses de cobre sobre o crescimento e qualidade de mudas de a\ue7oita-cavalo e aroeira-vermelha. O delineamento foi inteiramente casualizado num fatorial (2 x 5), sendo as duas esp\ue9cies florestais e cinco doses de cobre: 0, 64, 128, 192 e 256 mg kg-1 de solo, com cinco repeti\ue7\uf5es. Avaliaram-se altura da planta, di\ue2metro do colo, peso da mat\ue9ria seca radicular e da parte a\ue9rea, comprimento e \ue1rea superficial espec\uedfica radicular, e os \uedndices de qualidade de mudas: rela\ue7\ue3o entre altura da parte a\ue9rea e di\ue2metro do coleto; altura da parte a\ue9rea e peso da mat\ue9ria seca da parte a\ue9rea e o \ucdndice de Qualidade de Dickson. Os resultados revelaram que as doses testadas de cobre n\ue3o alteraram a qualidade de mudas de aroeira-vermelha, enquanto que o a\ue7oita-cavalo apresentou melhor qualidade com aplica\ue7\ue3o de 64 mg kg-1 de Cu. O cobre afeta primeiramente o sistema radicular das mudas de a\ue7oita-cavalo e aroeira-vermelha. A aroeira-vermelha \ue9 mais tolerante a elevadas doses de cobre do que o a\ue7oita-cavalo.Copper contamination has become common in areas of mining and grape culture in Rio Grande do Sul. The aim of this study was to evaluate the influence of the dose of copper on growth and seedling quality of acoita-cavalo and aroeira-vermelha. The experimental design was completely randomized in a factorial scheme (2 x 5), using two forestry species and five copper doses: 0, 64, 128, 192 and 256 mg kg-1 of soil, with five replications. Plant height, collar diameter, dry mass weight of root system and shoot, length and surface specific area of root system and index of seedlings quality were evaluated and relation between shoot height and haste diameter, shoot height and shoot dry mass weight and Dickson quality index were assessed. The results showed that the copper doses tested did not change the quality of aroeira-vermelha seedlings but acoita-cavalo displayed better quality with the application of 64 mg kg-1 Cu. Copper primarily affected the acoita cavalo and aroeira-vermelha root system. Aroeira vermelha was more tolerant to copper toxicity than acoita-cavalo and displayed better quality at higher copper doses