-Colonization in the State of Paraná has culminated in the devastation of large forest areas in the entire State. Degraded area recovery programs have emphasized the utilization of native species, but often the species indicated for local reforestation areas are unknown, as those areas are little known floristically. This study aimed to survey native species indicated for reforestation of areas in the Western region of the State of Paraná, classify those species as pioneer, secondary, or climactic, and indicate places of occurrence of matrices where seeds of those species could be collected. Bibliographic surveys in the specialized literature and research in the Herbarium Museu Botânico Municipal de Curitiba (MBM) and Herbarium of Universidade Estadual do Oeste do Paraná (UNOP) were conducted to identify potential species for degraded area recovery in the study of Western region of Paraná. In all, 115 species were selected, of which 22 are pioneer, 73 are secondary, and 20 are climactic. The bibliographic surveys suggests that pioneer species are the most indicated for the initial processes in the degraded areas recovery, while secondary and climactic species play a major role in area enrichment.Keywords: Reforestation, Pioneer species, Secondary species and climactic species. ESPÉCIES NATIVAS INDICADAS PARA RECUPERAÇÃO DE ÁREAS DEGRADADAS NO OESTE DO PARANÁ RESUMO -A colonização no Estado do Paraná culminou na devastação de grandes áreas florestadas em todo o Estado. Os programas de restauração de áreas degradadas enfatizam a utilização de espécies nativas, mas, muitas vezes, não se conhecem as espécies indicadas para reflorestamentos locais

ABSTRACT.This study aimed to analyze oxidative stress produced in cucumber seeds and seedlings when exposed to aqueous extract from dried leaves of leucaena, as well as its effect on the germination behavior, early growth and the antioxidant enzymes activity. It was evaluated the percentage, the speed index, the average time, the frequency and germination synchronization, the root length and shoot, as well as the catalase and peroxidase enzymes activity. There was no significant inhibitory effect of the leaf extracts on the germination percentage. However, there was delay in the seeds germination, as the extract proportion increased. A stimulatory effect of the extract compared to the shoot length was observed, however the root growth was significantly reduced. The catalase activities had a peak at 24 hours after soaking the seeds, however, the activities were reduced in seedlings. The peroxidase activity was low in the seeds and increased in the seedlings at 168 hours after immersion. The results suggest that there was oxidative stress due to allelochemicals present in the leaves extracts from leucaena, verified by germination and initial growth changes, causing alterations in the plants rootlets.Keywords: allelopathy, reactive oxygen species, antioxidant enzymes.Enzimas antioxidativas de sementes de Cucumis sativus são moduladas por extratos de Leucaena leucocephala RESUMO. Este trabalho objetivou analisar o estresse oxidativo produzido em sementes e plântulas de pepino quando submetidas a extrato aquoso de folhas secas de leucena bem como, seu efeito sobre o comportamento germinativo, crescimento inicial e atividade de enzimas antioxidantes. Foram avaliadas a porcentagem, índice de velocidade, tempo médio, frequência e sincronização da germinação, comprimento de raiz e parte aérea e atividade das enzimas catalase e peroxidase. Não houve efeito inibitório significativo dos extratos sobre a porcentagem de germinação. No entanto, houve atraso na germinação das sementes, à medida que se aumentou a proporção do extrato. Foi observado efeito estimulatório do extrato em relação ao comprimento da parte aérea, porém o crescimento da raiz foi reduzido significativamente. As atividades da catalase tiveram pico às 24 horas de embebição das sementes, tendo sido reduzido nas plântulas. No entanto, a atividade da peroxidase foi baixa nas sementes e teve aumento nas plântulas, às 168 horas após a embebição. Os resultados sugerem que houve estresse oxidativo devido aos aleloquímicos presentes nos extratos foliares de leucena, verificado pelas alterações na germinação e de crescimento inicial, o que causou alterações nas radículas das plântulas.Palavras-chave: alelopatia, espécies reativas de oxigênio, enzimas antioxidantes.

Beans are one of the most used foods to meet the energy needs of the Brazilian diet, requiring farmers to use high seed physiological potential. The aim was to evaluate the physiological quality of beans stored for 360 days. Analyses were performed at 0, 30, 90, 180, 270, and 360 days after receiving the seeds (S1 and S2) and grains (G1 and G2) of BRS Splendor. Tests of germination, accelerated aging, cold, speed of germination, average length of shoots, and root were performed. The experimental design was completely randomized split-plot in time and the means were compared through Tukey test at 5% probability. Seed germination was not affected in S2, while the drop in S1 and G1 was significant. The vigor of grains from field 1 declined from 91 to 50% and from 93% to 76% by accelerated aging and cold, respectively, after 360 days. The germination speed tests performed showed a decreased during the experiment. The grains from field 1 had lower physiological quality. The accelerated aging and cold tests, through the speed of germination parameter, showed decrease in the vigor of the Splendor BRS. The storage period influenced the physiological quality of the beans tested.

Leguminosae represents one of the leading families in floristic and phytosociological studies. Such variety can lead to difficulties in identification, particularly in sterile sample collection.

Fortes. 2020. Viability of using organic substrates according to toxicity tests and the antioxidant activities of tomato seeds and seedlings. Int. J. Agric. Nat. Resour. Plant growth can be directly influenced by the physical, chemical, and biological characteristics of their substrates. We tested the viability of using alternative substrates derived from agroindustrial residues by evaluating their effects on tomato (Solanum lycopersicum L.) germination and growth as well as the antioxidant activities in seeds and seedlings. The extracts were classified based on their principal carbon source: cotton waste (SA); sugarcane waste (SB); napier grass (SN); tree prunings (SP); and sawdust (SS). The chemical attributes of the substrates were analyzed, the physiological characteristics of tomato seed germination were determined, and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) were measured in tomato seeds and seedlings. The extracts from tree prunings and sawdust showed the highest germination indices and root lengths, while the cotton and sugarcane waste extracts showed the lowest values for the same variables, with high pH and electric conductivity values indicating possible toxicity; increased activities of antioxidant enzymes needed to correct physiological imbalances were detected. The substrates deemed most suitable for seedling production were those derived from tree prunings and sawdust.