Page 8 - Morphoanatomical investigations of cones and pollen in Cathaya argyrophylla Chung & Kuang (Pinaceae, Coniferales) under systematical and evolutional aspects
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V. M. Dörken and H. Nimsch                                        Feddes Repertorium 2014, 125, 25–38




























































            Figure 5. Cathaya argyrophylla; ripe microsporangia open at a preformed line to release the bisaccate pollen (MS =
            microsporangia; PR = phylloid rest).

            similarities to both complexes,  Cathaya shows some   veloped at present year’s shoots. In contrast to Cathaya
            unique features distinguishing it distinctly from all other   the young seed-cones of Pinus are also surrounded by
            recent Pinaceae.                                   bud scales, which persist at  the base of the stalk. Re-
             Among  Picea,  Larix and  Pseudotsuga the seed-   ceptive seed-cones of Cathaya, Pinus, Picea, Larix and
            cones are developed terminal at the shoot axis of the   Pseudotsuga are erect. In this respect the downward
            second or third year. In  Picea and  Pseudotsuga the   facing receptive seed-cones of  Picea orientalis are an
            shoot axis and the seed-cones are developed from dif-  exception (Owens et al. 1998; Runions et al. 1999). After
            ferent buds. Thus, the stalk of the seed-cones is sur-  pollination the seed-cones of most taxa change to a
            rounded by persisting bud scales. Contrasting to this,   pendulous position by active growth of the cone-axis.
            seed-cones of  Cathaya and  Pinus sprout sylleptically   Only in  Larix,  Abies and  Cedrus mature seed-cones
            together with the shoot axis. Thus, they are always de-  remain upright. In Cathaya only the small needle-leaves


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