Germinação de Astronium fraxinifolium Schott (Anacardiaceae) e detecção de fungos em sementes de Cariniana estrellensis (Raddi) Kuntze (Lecythidaceae)

Abstract

The present study evaluates the germination of seeds of Astronium fraxinifolium Schott (Anacardiaceae) and Cariniana estrellensis Raddi Kuntze species typical of deciduous forests, Requests for pre-germination treatments. Plant bioregulators are substances that can enhance plant growth and development and stimulate cell division, may interfere with seed germination. The diaspores used were initially disinfected in sodium hypochlorite solution (1%) for 10 min. for the work of germination, I used six pre-germination treatments with 4 repetitions with 25 seeds each placed in BOD at 250C, being: T0: Control (seeds without pre-imbibition); T1: treatment with soaking in water; T2: seeds immersed in acid gibberellic GA3 (500ppm); T3: seeds immersed in gibberellic acid GA3 (1000ppm); T4: seeds immersed in Stimulate® at a concentration of 5ml.L-1 and T5: seeds immersed in Stimulate® at a concentration of 10 ml.L-1 all for a period of 12 hours at temperature environment (25°C). These treatments were mounted on two substrates (1: On paper and 2: Between Germitest® paper). The effects of different treatments and substrates on germination of the diaspores were evaluated using ANOVA, followed by the 5% SNK test. In relation to pre-germination treatments, no changes in germination rates were passed on germination. The germination of seeds submitted to pre-germination treatments did not differed from the witness. There was no significant difference in the treatments tested within the different substrates. There was no difference between treatments in the germination of A. Fraxinifolium ranging from 57 to 73%. For the Germination Speed Index (GVI) the treatments between paper soaked in Stimulate® at 10 ml.L-1 best grade results. For C. estrellensis seeds, on the 15th day after sowing, a high rate of fungal contamination that would affect the germination process, thus fungi were removed from the surface of the seed with the aid of a needle and placed on slides with lacto-glycerol blue dye for observation in optical scope. According to collected data the following genera of fungi were identified: Aspergillus sp., Chaetomium sp., Cladosporium sp., Fusarium sp., Lasiodiplodia sp., Paecilomyces sp., Penicillium sp., Penicillium oxalicum, Phiallophora sp., Phoma sp. The fungus with the greatest frequency between treatments was Chaetomium sp. Phoma fungus was only detected in seeds placed to germinate between paper. (Paper roll).