Fenologia de espécies arbóreas nativas no Jardim Botânico da Universidade Federal de Santa Maria, Santa Maria - RS

Abstract

The objectives of this study were: to review literature on the concepts of plant phenology, focusing on tree phenology work performed in the state of Rio Grande do Sul, Brazil, in chapter I follow the vegetative and reproductive phenology of 20 species native tree of the state of Rio Grande do Sul - RS existing at the Botanical Garden of the Universidade Federal de Santa Maria - UFSM and associating the phenological events observed with the astronomical and meteorological variables (day length) and Chapter II, set up a schedule using phenological phenophases of twenty different native species of Rio Grande do Sul - RS. The plant phenology is an ecological study that accompanies the repetitive events of plants for a minimum period of one year. Generally, the data are divided into vegetative growth stages: mature leaves, leaf fall and flushing, and reproduction: flowering (flower buds and flowering) and fruit (green fruit / immature and mature fruit), and gain more importance when related to meteorological variables and climatic conditions. The twenty species selected were: Lithraea molleoides (Vell.) Engler, Schinus terebinthifolius Raddi, Handroanthus heptaphyllus (Vell.) Mattos, Cordia americana (L.) Gottschling & J.S.Mill., Sebastiania commersoniana (Baill.) L.B. SM. & Downs, Albizia niopoides (Benth) Killip ex, Enterolobium contortisiliquun (Vell.) Morong, Inga uruguensis Hook. & Arn., Parapiptadenia rigida (Benth.) Brenan, Luehea divaricata Mart., Myrsine coriacea (Sw.) R.Br. ex Roem. & Schult., Blepharocalyx salicifolius (Kunth) O. Berg, Eugenia uniflora L., Myrciaria tenella (DC.) O.Berg., Prunus myrtifolia (L.) Urb., Zanthoxylum rhoifolium Lam., Helietta apiculata Benth., Casearia sylvestris Sw., Allophylus edulis (A. St.-Hil., Cambess. & A. Juss.) Radlk. e Cupania vernalis Cambess. The methodology was based on direct observations and biweekly during the period of the August/2010 agosto/2011. The stages of budding, leaf fall, flowering (anthesis and button) and fruit (green fruit / immature and mature fruit) were observed in 4-10 randomly selected individuals for each species. The stages were associated with meteorological variables (precipitation and air temperature) and variable astronomical (day length) obtained from the Meteorological Station of UFSM. Data analysis was performed using the phenological activity index (presence / absence) and the Index of Fournier. Based on the results, schedules were developed vegetative and reproductive phenology (flowering and fruiting). In vegetative phenology was observed that the budding was constant throughout the observation period, the leaf fall, more pronounced in autumn and winter, and mature leaves with full photosynthetic capacity peaked in spring and summer and in winter with a reduction of almost 50%. In the largest reproductive phenology of flowering peaks were observed in spring and early summer and fruiting occurred mainly in summer and early fall. The length of day and air temperature correlated significantly with both clones, however, these were not significant with the rainfall. Thus, the results of the vegetative and reproductive phenological calendars of tree species were similar to those mentioned in the literature.