Abstract
The embryogeny of the wild oat (Avena fatua L.) was studied in detail. The pattern of embryo development was observed to be similar to the other investigated grass taxa, conforming to thePoa variation of the Asterad type. The embryogeny and anatomy of young seedlings showed that the embryo of the wild oat was not monocotylous, but dicotylous. The scutellum of the embryo, as reported for other grasses, was regarded as the first cotyledon, and the first leaf primordium, which developed later into a photosynthesizing leaf and situated opposite the scutellum, was interpreted as the second cotyledon. Observations indicated that the cotyledons of the embryo were placed lateral to the shoot apical meristem, which was terminal in position. The cotyledons were found to be dimorphic in structure and function. The scutellum, a modified cotyledon, functioned as a suctorial organ, transporting nutrients from the endosperm to the embryo axis. The second cotyledon or the first true leaf supplied nutrients directly to the embryo axis through the process of photosynthesis.
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Shuma, J.M., Raju, M.V.S. Is the wild oat embryo monocotylous?. Bot Mag Tokyo 104, 15–23 (1991). https://doi.org/10.1007/BF02493400
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DOI: https://doi.org/10.1007/BF02493400