释义 |
nyctinastic, a. Bot.|nɪktɪˈnæstɪk| [a. G. nyctinastisch (W. Pfeffer Pflanzenphysiologie (ed. 2, 1904) II. xii. 476): see nycti- and nastic a.] Of the movements of flowers or leaves, caused by a regular cycle of changes in light and temperature. So nyctiˈnastism, ˈnyctinasty, movement of this kind. Cf. nyctitropic a., nyctitropism.
1906A. J. Ewart tr. Pfeffer's Physiol. Plants III. ii. 97 Since the term ‘tropism’ is reserved for curvatures produced by unilateral stimuli, it becomes necessary to change the term ‘nyctitropic’ used by Darwin..into that of ‘nyctinastic’. Ibid. 101 There is no reason for restricting the term nyctinastic to pronounced sleep-movements. 1921J. Small Textbk. Bot. xxvi. 378 Nyctitropism or Nyctinastism includes the opening and closing of flowers.., also the rising and falling of leaves..in response to the stimulation of changes in temperature and light. 1936J. B. Hill et al. Botany ix. 228 Certain leaves as well as flowers may fold up at night. These so-called ‘sleep movements’ of plants, brought about by the alternation of night and day, are the most common nasties and are termed nyctinasties. 1968New Scientist 26 Dec. 717/1 The closing of the leaves..in fact, happens after the transfer of the plants to darkness—a so-called nyctinastic or ‘sleep’ movement. |