In 2000 there was an oil spill at the Getúlio Vargas Refinery (REPAR) in Paraná. Nearly five years after contamination and the use of bioremediation, a study was carried out to identify the effects of the contaminated soil and the bioremediated soil on the germination and initial growth of C. xanthocarpa. The experiment was established with soil from REPAR, with three treatment groups: contaminated soil (C), bioremediated soil (B) and uncontaminated soil (U); with five repetitions of 50 seeds each. There was no significant difference in the percentage of germination and the speed of germination index. The production of total biomass (30 -60 days) and shoot biomass (60 days) was greater in the bioremediated soil compared to the other treatments. The averages for the root biomass were lower in the contaminated soil than in the bioremediated soil. The shoot length and the total length of the seedling in the contaminated soil and uncontaminated soil were lower than in the bioremediated soil.Keywords: biomass, gabiroba, hydrocarbon contamination, seedling growth. Germinação e crescimento inicial de Campomanesia xanthocarpa O. Berg. (Myrtaceae), em solo contaminado com petróleo e solo biorremediado ResumoEm 2000, ocorreu um vazamento de petróleo na área da Refinaria Getúlio Vargas (REPAR), no Paraná. Após cerca de cinco anos da contaminação e utilização do processo de biorremediação, pretendeu-se identificar os efeitos do solo contaminado e do solo biorremediado na germinação e no crescimento inicial de C. xanthocarpa. O experimento foi montado com solo da REPAR, com três tratamentos -solo contaminado (C), solo biorremediado (B), solo não contaminado (U) -e cinco repetições com 50 sementes cada. Não houve diferença significativa na porcentagem e no índice de velocidade de germinação. A produção de biomassa total (30 -60 dias) e biomassa da parte aérea (60 dias) foram maiores no tratamento biorremediado em relação aos demais tratamentos. As médias para a biomassa da raiz foram menores no solo contaminado do que no solo biorremediado. O comprimento da parte aérea e o comprimento total da plântula no solo contaminado e no não contaminado foram menores do que no biorremediado.Palavras-chave: biomassa, gabiroba, contaminação por hidrocarbonetos, crescimento de plântula.

RESUMO:O objetivo desse trabalho foi avaliar a atividade alelopática dos lixiviados das raízes e folhas secas de Asemeia extraaxillaris sobre o crescimento de corda de viola Ipomoea cordifolia em casa de vegetação, para avaliação dos efeitos sobre o estresse oxidativo. Nos bioensaios foram utilizadas três concentrações (0,25 -5,00 e 10,00 g) e um controle, com quatro repetições de 10 plantas, cultivadas em solo durante 30 dias. Os lixiviados possuem ação alelopática e o maior efeito foi verificado para o pó das raizes. O efeito inibitório foi dose-dependente e o aumento do estresse oxidativo foi observado pelos níveis da catalase, peroxidase, superóxido dismutase, glutationa redutase, peroxidação lipídica e síntese de formazan. Concluiu-se que A. extraaxillaris possui substâncias capazes de afetar a emergência, o crescimento e o estresse oxidativo de I. cordifolia.Palavras chave: estresse oxidativo, lixiviação, fitoherbicida, mentol-do-campo, corda-de-viola.ABSTRACT: Allelopathic activity of leachates from Asemeia extraaxillaris (Polygalaceae) on the growth of Ipomoea cordifolia. The purpose of this article is to assess the allelopathic activity of leachates from the roots and dried leaves of Asemeia extraaxillaris on the germination and growth of corda de viola (Ipomoea cordifolia) in a greenhouse, and evaluate its effect on oxidative stress. For the bioassays, three concentrations (0.25, 5.00, and 10.00 g) and one control were used, with four replications of 10 plants, cultivated in soil for 30 days. The leachates exhibited allelopathic action, and the greatest effect was found in the root powder. The inhibitory effect was dose-dependent and the increase in oxidative stress was observed by the levels of catalase, peroxidase, superoxide dismutase, glutathione reductase, lipid peroxidation, and formazan synthesis. It was affirmed that A. extraaxillaris contains substances capable of affecting seedling emergence, growth, and oxidative stress in I. cordifolia.

Senna ocidentalis is a weed, native to Brazil, considered to infest crops and plantations, and is responsible for yield losses of several crops, particularly soybean. The aim of this work was to evaluate if the Croton argenteus extract and fractions possess phytotoxic activity on S. ocidentalis. The crude ethanolic extract (CEE) and its hexanic (HF), chloroformic (CLF) and ethyl acetate (EAF) fractions were tested in germination, growth, oxidative stress increase, Adenosine triphosphate, L-malate and succinate synthesis. The crude extract and its fractions slowed down the germination of S. ocidentalis and decreased the final percentage of germination. Oxidative stress was also increased in the seedlings, by an increase of catalase, peroxidase, superoxide dismutase, glutathione reductase and lipid peroxidation; and it became clear that the ethyl acetate fraction was more phytotoxic. The results indicate that the crude extract and fractions of C. argenteus compromise the mitochondrial energy metabolism, by the inhibition of mitochondrial ATP production, with a decrease in the production of L-malate and succinate. The ethyl acetate fraction of C. argenteus showed high activity on germination and growth, and these effects take place by means of mitochondrial metabolism alterations and increase the oxidative stress, leading the seedling death.