The Seedless Vascular Plants: Ferns and Their Relatives

Features of Seedless Vascular Plants 1 Features of Seedless Vascular Plants 1. Xylem and phloem present • internal conducting tissues for water and food, respectively 2. Spores, but no seeds 3. Ferns and relatives ("fern allies")

Reproduction in the ground pine Lycopodium 1. Strobilus (conelike stucture)formed in many species. 2. Sporophylls with sporangia. Meiosis occurs in sporangia. 3. Meiospores germinate in the soil and produce gametophytes with archegonia and antheridia. 4. Fertilization occurs in archegonium, producing zygote. 5. Zygote develops into mature sporophyte. 6. Asexual propagation may occur by bulbils, small small budlike structures produced in the axils of leaves.

Reproduction in the spike moss Selaginella 1. Sporangia produced on microsporophylls and megasporophylls. 2. Microsporangia and megasporangia produce microspores and megaspores. 3. Microspores develop into male gametopyte. 4. Megaspores develop into female gametophytes. 5. Gametophytes develop within the confines of the microspore and megaspore walls. 6. Fertilization and development of sporophytes similar to ground pines.

Human & Ecological Relevance of Club Mosses and Quillworts 1. Little economic importance. 2. Lycopodium: spores used as flash powder and other uses. 3. Selanginella: resurrection plants, sold as novelties. 4. Lycopodium: woven into wreaths and holiday decorations. Isoetes: quillwort corms can be eaten by animals, birds, and humans. Equisetum- used for polishing of metals Azolla-used as Bio-fertilizers