REFERENCES
- Ashton , P. and Walmsley , R. 1976 . The aquatic fern Azolla and its Anabaena symbiont . Endeavour , 35 : 39 – 43 .
- Dahlgren , R. 1980 . A revised system of classification of the angiosperms . Bot. J. Linn. Soc. , 80 : 91 – 124 .
- Harborne , J.B. 1965 . Plant polyphenols XIV. Characterization of flavonoid glycosides by acid and enzymatic hydrolyses . Phytochemistry , 4 : 107 – 120 .
- Harborne , J.B. 1966 . Comparative biochemistry of flavonoids. II. 3- desoxyanthocyanins and their systematic distribution in ferns and gesnerads . Phytochemistry , 5 : 589 – 600 .
- Harborne , J.B. Flavonoids in the environment: structureactivity relationships . Proceedings of a meeting on plant flavonoids in biology and medicine . August–September 1987 , Strasbourg. Plant Flavonoids in Biology and Medicine II , Edited by: Cody , V. pp. 17 – 27 . N. York : Alan R. Liss Inc. . In
- Hartwig , U.A. , Maxwell , C.A , Joseph , C. and Philips , D. 1990 . Chrysoeriol and luteolin released from Alfafa seeds induced nod genes in Rhizobium meliloti . Plant Physiol. , 92 : 116 – 122 .
- Hegnauer , R. 1962 . Chemotaxonomie der Pflanzen , Vol. I , 290 – 291 . Berlin : Birkhauser Verlag .
- Heywood , V.H. 1973 . The role of chemistry in plant systematics . Plant Syst. Evol. , 34 : 355 – 375 .
- Holst , R.W. 1977 . Anthocyanins of Azolla . Am. Fern J. , 67 : 99 – 100 .
- Ishikura , N. 1982 . 3-Desoxyanthocyanin and other phenolics in the water fern Azolla . Bot. Mag. Tokyo , 95 : 303 – 308 .
- Leizerovich , I. , Fleminger , G. , Kardish , N. , Frensdorff , A. and Galun , M. 1988 . Polyphenols, and not lectins, are responsible for hemagglutinating activity in extracts of Azolla filiculoides Lam . Symbiosis , 5 : 209 – 222 .
- Lumpkin , T.A. and Plucknett , D.L. 1980 . Azolla — botany, physiology and use as a green manure . Economic Bot , 34 : 111 – 153 .
- Martin , A. 1976 . Some structures in Azolla megaspores and an anomalous form . Rev. Palaeobotan. Palynol. , 21 : 141 – 169 .
- Moore , A.W. 1969 . Azolla: Biology and agronomic significance . Bot. Rev. , 35 : 17 – 34 .
- Pereira , A.L , Teixeira , G. , Sevinate-Pinto , I. , Antunes , T. and Carrapiço , F. How many Azolla species exist in Portugal? A preliminary approach . Abstracts of the EWRS 10th International Symposium on Aquatic Weeds . September 22–26 , Lisbon.
- Perkins , S.K. , Peters , G.A. , Lumpkin , T.A. and Calvert , K.E. 1985 . Scanning electron microscopy of perine architecture as a taxonomic tool in the genus Azolla Lamarck . Scan. Electron Microsc. , 4 : 1719 – 1734 .
- Peters , N.K. , Frost , J.W. and Long , S.R. 1986 . A plant flavone, luteolin, induces expression of Rhizobium meliloti nodulation genes . Science , 233 : 977 – 980 .
- Pieterse , A. , De Lange , L. and Van Vliet , J.P. 1977 . A comparative study of Azolla in the Netherlands . Acta Bot. Neerl. , 26 : 433 – 449 .
- Redmond , J.W. , Batley , M. , Djordjevic , M. , Innes , R. , Kuempel , P. and Rolfe , B. 1986 . Flavones induce expression of nodulation genes in Rhizobium . Nature , 323 : 632 – 635 .
- Richardson , P.M. 1989 . Flavonoids of the “fern allies” . Bioch. Syst. Ecol. , 17 : 155 – 160 .
- Saunders , R.M.K. and Fowler , K. 1992 . A morphological taxonomic revision of Azolla Lam. Section Rhizosperma (Mey.) Mett . (Azollaceae). Bot. J. Linn. Soc. , 109 : 329 – 357 .
- Saunders , R.M.K. and Fowler , K. 1993 . The supraspecific taxonomy and evolution of the fern genus Azolla (Azollaceae) . Plant Syst. Evol. , 184 : 175 – 193 .
- Soeder , R.W. 1985 . Fern constituents: Including occurrence, chemotaxonomy and physiological activity . Bot. Rev. , 51 : 442 – 536 .
- Teixeira , G , Carrapiço , F. and Gomes , E. Biological and chemical study of Azolla filiculoides Lam. and A. pinnata R. Br. Abstracts of the EWRS 9th International Symposium on Aquatic Weeds . September 12–16 , Dublin.
- Teixeira , G. 1999 . “ Estudo biológico e fitoquímico de Azolla filiculoides Lam. and A. pinnata subsp africana (Desv.) R. M. K. Saunders & K. Fowler ” . In Ph.D. Thesis , 222 – 222 . Lisbon University .
- Voirin , B.M. 1967 . Recherches chimiotaxonomiques sur des plantes vasculaires. Distribution des flavonoides chez les Filicinées . Compt. R. de l' Acad. des Sc. Paris, Serie D , 264 : 665 – 668 .
- Wagner , H. and Bladt , S. 1996 . Plant drug analysis: a thin layer chromatography atlas , 2nd ed. , 362 – 362 . Berlin : Springer-Verlag .
- Watanabe , I. and Van Hove , C. 1996 . “ Phylogenetic, molecular and breeding aspects of Azolla-Anabaena symbiosis ” . In Pteridology in Perspective , Edited by: Camus , J.M. , Gibby , M. and Johns , R.J. 611 – 619 . 743 p – 743 p . Kew : Royal Botanical Gardens . In