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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