Fernanda Ventorim Pacheco

Crescimento inicial de Dalbergia nigra (Vell.) Allemão ex. Benth. (Fabaceae) e Chorisia speciosa A.St.-Hil (Malvaceae) sob diferentes níveis de sombreamento

The seedling production with conservation or economic purpose depends on knowledge related with the growth and development of plants. The study of plants under different environmental conditions, allows to define ways to improve crops. The present study aimed to evaluate the growth of Dalbergia nigra (rosewood caviuna) and Chorisia speciosa (kapok) seedlings cultivated in greenhouses in order to determine the appropriate shading for growing those species and relate their responses to the ecological context. Seeds were sown and grown in greenhouses at 0, 22, 50, 70, 84 and 91% shading. The growth variables assessed were plant height, stem diameter, leaf area and height/diameter. Data were collected at 30, 60, 90 and 180 days after emergence. Seedlings of Dalbergia nigra had a greater height, stem diameter and leaf area in the treatments with intermediate shading (50%, 70% and 84% shade) and showed characteristics of shade-tolerant species and approaching the later stages of succession to late secondary species climax. Moreover, the seedlings of Chorisia speciosa showed better growth in the treatment without shade (0%) and light shading treatments (20 and 50%), with characteristics of species heliophytic plants in the early stages of succession, as pioneer plants or early secondary.

Fator de resposta do alecrim-pimenta a diferentes lâminas de irrigação

Evaluating the response of medicinal plants to irrigation is not very common, especially when they are native species with economic potential , such as the Lippia sidoides . Thus, this study aimed at evaluating the Lippia sidoides response, by using the Ky coefficient, and growth, under different irrigation depths. The coefficients were determined from the dry matter and essential oil yields. The experiment used a randomized blocks design, with treatments consisting of seven irrigation depths (0.5, 0.75, 1.0, 1.2, 1.4, 1.65 and 1.9 of the Eto), with three replications. The ETo was evaluated by using the Penman-Monteith method and the ETr according to the soil water balance. Growth was determined by measuring the stem diameter and height, at 35, 56, 77, 98 and 119 days after transplanting. At 120 days of cultivation, samples were collected to determine the dry matter and essential oil yields. The plant responded to water deficit with coefficients above 1.0, for both dry matter and essential oil yields. Growth was positively affected by irrigation, reaching higher values for stem diameter and height when the highest irrigation depths were used.

Growth and production of volatile compounds of yarrow (Achillea millefolium L.) under different irrigation depths

Yarrow (Achillea millefolium L., Asteraceae) is an important medicinal plant used worldwide for its medicinal properties such as the analgesic, antioxidant and anti-inflammatory ones. The aim of this study was to evaluate the growth and production of photosynthetic pigments and of volatile constituents of Achillea millefolium L. under different irrigation depths. The treatments were the application of 55, 110, 220, 440 and 880 mm of water for a period of 110 days. Data were submitted to polynomial regression analysis at 5% probability, while the volatile constituents were analyzed by standard deviation. Different irrigation depths provided quadratic growth responses being the highest dry matter production at the depth of 440 mm. The contents of chlorophyll a, b, total and carotenoids were higher at the lower depth tested (55 mm). The major volatile compounds identified were sabinene, 1,8-cineol, borneol and β-caryophyllene. Increased water availability reduced the complexity of the volatile fraction of essential oil. Thus, it is recommended that the species be cultivated at 440 mm irrigation depth to have a higher production of dry matter and lower variation in the volatile profile of the essential oil.

Growth, photosynthetic pigments and production of essential oil of long-pepper under different light conditions

Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN) and blue (BN) both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade). The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.

Resistance Mechanisms of Peltophorum dubium (Sprengel) Taubert Submitted to Flood Conditions

Peltophorum dubium (Sprengel) Taubert seedlings were submitted to 60 days of flooding, with and without Ca+. During this period, growth, root anatomy and chlorophyll content were analyzed. The relative growth rates (RGR) of roots and shoots were higher in non-flooded plants. The flooded treatments, with and without Ca+, have affected the roots growth but did not affect the shoot and the stem diameter. The anatomy analysis showed thickening of the sclerenchyma in 15 and 60 days in the flooded treatments with and without Ca+, and the vessel diameter was smaller at 45 days. The chlorophyll content differed, however it was not statistically significant. The results indicate that Peltophorum dubium as candidate specie for reforestation in areas subjected to continuous flooding for up to 60 days, since no mortality was observed.