Key Difference – Ascospore vs Basidiospore
Fungi are a group of microorganisms which include harmful and beneficial species. They serve as the main decomposers in the environment. Fungi show sexual and asexual reproductive mechanisms in which sexual and asexual spores are formed as a medium of propagation. Fungi spores are very similar to seeds. They germinate and give rise to a new fungal colony. Spores have simple structures. However, there is a wide variety of fungal spores, which differ from shapes, colours, forms and sizes. Fungal spores are useful in characterization and differentiation of fungal species. Asexual spores are produced either in sporangia or as conidia. Sexual spores are produced from mating between two different fungal hyphae. There are four major kinds of sexual spores named oospores, zygospores, ascospores and basidiospores. The key difference between ascospore and basidiospore is that ascospore is a sexually produced spore of fungal group ascomycetes while basidiospore is a sexually produced spore of fungal group basidiomycetes.
CONTENTS
1. Overview and Key Difference
2. What is an Ascospore
3. What is a Basidiospore
4. Side by Side Comparison – Ascospore vs Basidiospore
5. Summary
What is an Ascospore?
Ascospore is a sexual fungal spore produced by ascomycetes fungi. Ascospores are formed as a result of sexual reproduction between two different ascomycetes fungi. Ascospores are very specific to ascomycetes since they are produced inside ascomycetes’ specific special microscopic structures called ascus. Ascus is a cylindrical or spherical structure developed within the cells or hyphae of the fungus. A typical ascus bears eight ascospores. Hence, it was given the name ascus, referring to the structure consisting of eight spores. There are certain species which produce one spore per ascus and also over a hundred spores per ascus.
Asci are internal structures developed within some kind of enclosing structures of ascomycetes. Therefore, ascospores are also produced internally without protruding from the hyphae. Formation of ascospores is a complex process which follows two consecutive cell division processes: meiosis and mitosis. The diploid zygote divides by meiosis to produce four haploid nuclei. Each of the four haploid nuclei duplicates by mitosis to produce eight haploid cells called ascospores inside an ascus.
Ascospores can be coloured or hyaline and can have different shapes.Common fungal species which produce ascospores include Penicillium spp, Aspergillus spp, Neurospora spp, yeast, etc.
Figure 01: Ascospore formation in Neurospora crassa
What is a Basidiospore?
Basidiospore is a sexual spore produced by basidiomycetes fungi. Basidiomycetes include mushrooms, rusts, smuts and shelf fungi, which are commonly known as club fungi. Basidiospores are specific to basidiomycetes since they are produced inside basidiomycetes’ specific special structures called basidia. Basidia are specialized fungal cells which develop externally from the hyphae. A typical basidium contains four haploid basidiospores. These spores are produced as a result of sexual reproduction between two basidiomycetes fungi. Basidium develops four sterigma on its surface, which bears basidiospores.
Basidiospores bear attachment pegs called hilar appendage in each spore, which occurs due to the attachment with the basidium; it can be used to identify basidiospores from other spores. Basidiospores are asymmetrical and single celled. They possess different shapes ranging from spherical to oval to oblong to cylindrical. Basidiospores are served as the main dispersal unit of basidiomycetes fungi.
Basidiospores are formed during the sexual reproduction of basidiomycetes. One basidium produces four basidiospores externally by meiosis. Millions of basidia exist under one cap of a mature basidiocarp. Hence, one basidiocarp is able to produce billions of basidiospores at a time. Some species of Agaricus can produce billions of basidiospores from one basidiocarp. Puffball fungus Calvatia gigantea is identified as a species which produces about five trillion basidiospores.
Figure 02: Basidiospore production by Agaricus spp.
What is the difference between Ascospore and Basidiospore?
Ascospore vs Basidiospore |
|
| Ascospore is a sexual spore produced by fungi ascomycetes | Basidiospore is a sexual spore produced by fungi basidiomycetes. |
| Production | |
| Ascospores are produced inside a structure called ascus. | Basidiospores are produced by basidia. |
| Spore Number Borne by One Structure | |
| A typical ascus bears eight ascospores. | A typical basidium produces four basidiospores. |
| Spore Production | |
| Ascospores are produced endogenously. | Basidiospores are produced exogenously. |
Summary – Ascospore vs Basidiospore
Ascospore and basidiospore are two types of sexual spores produced by fungi. Ascospores are specific to fungi ascomycetes, and they are produced inside asci. Basidiospores are specific to basidiomycetes, and they are produced in basidia. Ascospores develop endogenously while basidiospores develop exogenously. This is the difference between ascospore and basidiospore.
Reference:
1. “Two Major Groups.” Ascomycetes and basidiomycetes. N.p., n.d. Web. 22 May 2017. https://www.anbg.gov.au/fungi/ascomycetes-basidiomycetes.html
2. Moulds and their characteristics. N.p., n.d. Web. 22 May 2017. http://website.nbm-mnb.ca/mycologywebpages/Moulds/Characteristics.html
3. Spores in Fungi. N.p., n.d. Web. 22 May 2017. <http://agriinfo.in/?page=topic&superid=5&topicid=1990>
Image Courtesy:
1. “Neurospora crassa life cycle” By Chaya5260 – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “03 02 09 life cycle of Agaricus sp., Agaricales Basidiomycota (M. Piepenbring)” By M. Piepenbring – M. Piepenbring (CC BY-SA 3.0) via Commons Wikimedia