III - Contribuição para o estudo biológico e ecológico das Podostemaceae do salto do Piracicaba

III - Contribuição para o estudo biológico e ecológico das Podostemaceae^* do salto do Piracicaba

Walter Radamés Accorsi

Prof. de Botânica Geral e Discritiva da E. S. A. "Luiz de Queiroz"

SUMMARY

1 - The Author, in this 3 thd. contribution, concludes the study of the biology and ecology of the species Tristicha trifaria (Willd.) Spreng. and Mourera aspera (Bong.) Tul., both of the Piracicaba Fall.

2 - According to the results of Dr. Peter van Royen (State Herbarium of Leiden, Holland), who made a complete revision of Podostemaceae of the Piracicaba Fall, the species Tristicha hypnoides (St. Hil.) Spreng. var. Hilarii Tul. and Mnioppsis Glazioviana Warm, correspond, respectively, to theTristicha trifaria (Willd.) Spreng. and Mniopsis weddelliana Tul. Apinagia Accorsii Toledo was transferred by Royen to the genus Wettsteiniola. So, its new name is Wettsteiniola accorsii (Toledo) v. Royen.

3 - Propagation by seeds may occur in the following places:

a) placenta of partially open fruits;

b) external and internal walls of the open capsules;

c) pedicels of the fruits;

d) remains of rhizomes, branches, etc.

e) organic residues accumulated in water holes in the fall;

f) clean rocks, in which the little groups of seedlings seems to be a colony of algae.

Seeds adhere to the substrata above by means, of a mucilage produced by the transformation of the external integuments in contact with water.

4 - In the growth of the four species below it was found in Piracicaba Fall conspicuous zoning so scattered:

a) Wettsteiniola accorsii (Toledo) v. Royen, in rocks situated just within the water fall, where velocity of the current and aeration of the water are very high.

b) Tristicha trifaria (Willd.) Spreng. and Mniopsis weddelliana Tul., in rocks at some distance (100 m more or less) upstream until near the bridge across the river.

c) Mourera aspera (Bong.) Tul., 300 m upwards the bridge. 5- During 1949, the ecological conditions of the Piracicaba

Fall were changed due to the following factors:

a) dry season very long, begining from last period of June until 30 november;

b) stopping, during four months, of water from the Atibaia river (one of the components of Piracicaba river) near to the city of Americana, in the place where a new station of the Companhia Paulista de Força e Luz was build. In consequence, most of the Podostemaceae died. On the dry rocks there were only fruits and dried plants.

6 - Tristicha trifaria has the same biological and ecological behavior as the Mniopsis weddelliana,.

7 - The vegetative propagation of Tristicha trifaria is made by increasing of its branches, production of stolons with vegetatives buds and regeneration of old parts in especial conditions of water and aeration.

8 - Mourera aspera has the same vegetative propagation as the Wettsteiniola accorsii; it produces stolons (in very little percentage) with vegetative buds, branches of the rhizomes and regeneration of active old parts.

9 - Frequently, there is, on the plants an accumulation of sand, silt, loam, organic substances, and so on. The quantity of material stored depends of the purity of the water, of the morphology of the plants and of the situation on the fall.

10 - In extrem conditions of dry heat, the surviving of the species in its habitat depends exclusively from germination of seeds in the mentioned substrata. Exceptionally, some plants survive in a few water pockets full with the weak remaining current.

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BIBLIOGRAFIA CONSULTADA

ACCORSI, W. R., 1944 - Contribuição para o Estudo Biológico e Ecológico das Podostemaceae do Salto de Piracicaba. Anais da E. S. A. "Luiz de Queiroz". Piracicaba.

----------, 1946 - II - Contribuição para o Estudo Biológico e Ecológico das Podostemaceae do Salto de Piracicaba. 3: 399-424 f. 1-27. Piracicaba. ENGLER, A., 1930 - Die Natürlischen der Pflanzenfamilien. Band. 18. Verlag von Wilhem Engelmann. Leipzig.

LOFGREN, A., 1917 - Manual das Famílias Naturais Phanerogamas. Rio de Janeiro. Imprensa Nacional.

MARTIUS, C. F. PH., 1872-1873 - Flora Brasiliensis. IV Pars I. Moachii in Typographia Regia C. Wolf et Fil. et in Offic. Lithograph. S. Minsinger.

PIO CORRÊA, M., 1931 - Dicionário das Plantas Úteis do Brasil e das Exóticas Cultivadas. Vol. II. Rio de Janeiro. Ministério da Agricultura.

RAHU, W., 1937 - Nova Acta Leopoldina. Neue Folge. Band. 4. Nummer 24. Halle (Saale).

RENDLE, A. B., 1938 - The Classification of Flowering Plants. Vol. II. Cambridge.

ROYEN, PETER VAN., 1951 - The Podostemaceae of New World Part I. Firma P. Harte Bergen Op Zoom.

TOBLER, F., 1933 - Beitrage zur Oekologie und Biologie brasilianischer Podostemaceen. Flora. Neue Folge. 28: 286-300.

WILLIS, J. C, 1915 - The Origin of the Tristichaceae and Podostemonaceae. Annals of Botany. 29: 229-306.

---------, 1940 - The Course of Evolution. Cambridge. At the University Press.

*

SPRAGUE (citado por P. VAN ROYEN, 1951) friza que o nome certo da família é Podostemaceae e não Podostemanaceae.

Datas de Publicação

• Publicação nesta coleção
  06 Nov 2012
• Data do Fascículo
  1951