Life Cycle of Pteridophyta

Life Cycle of Pteridophyta
Vegetative reproduction of Pteridophyta is by rhizome. Rhizome grows all of direction as colony. Pteridophyta have life cycle known as metagenesis with two generations, they are sporophyte and gametophyte generations.

• Sporophyte Generation. Sporophyte generation producing spores is a Pteridophyta itself. So, the Pteridophyta that we see in daily life is sporophyte generation. This generation is longer than gametophyte. Sporophyte can grow and produce some bud in order to add new individual. It is called asexual reproduction. While the spores is exited from sporangium and spread by wind, if it fall in suitable place it will grow as new individual plant that called as protalium.

• Gametophyte Generation. Gametophyte generation is producing gamet known as protalium. Protalium is talus formed have 1-2 cm approximately in size. This form like a heart that is usually lives in moist place. Unlike Bryophyta, gametophyte in Pteridophyta only lives on some weeks. Protalium formed antheridium as male gamet and archegonium as female gamet. Antheridium produce sperm while archegonium produce ovum. Fertilization between sperm and ovum formed zygote. Furthermore, zygote will grow as new Pteridophyta that have roots, stems, and leaves.

Life Cycle (Metagenesis) of Pteridophyta

 

Differences between sporophyte and gametophyte generations in Pteridophyta

Based on kinds of spores that produced by Pteridophyta, it divided into homospores, heterospores, and transitions fern.

• Homospores Fern. Homospores fern is only produce one kind of spore. It also known as monoceous fern, for example is Lycopodium sp (wire fern). This fern have stem like a wire that lives creeping on the other plant.  

• Heterospores Fern. Heterospores fern produce two kinds of spores. The small spores called microspores and produce antheridium as male gamet, while large spores called macrospores and produce archegonium as female gamet. For examples are Selaginella sp and Marsilea sp. 

•  Transitions Fern. Transitions fern produce spores that have same in size but is differenced into male spores (+) and female spores (-). Example is Equisetum debile (tail horse fern).