Ascocarp

Ascocarp in fungi is a reproductive structure that belongs to the fungus of the phylum Ascomycota. The ascocarp fruiting body contains and protects the asci and spores. Understanding the ascocarp types and examples helps students recognize different fungal species and learn their life cycles. In this article, we will cover Ascocarp in detail.

Ascocarps, also called apothecia or ascomata, are the reproductive structures of fungi within the Ascomycota phylum. This word “Ascocarp” was first used in 1882. It is the structure where sexual reproduction takes place in these fungi. Ascocarps come in various forms such as apothecium, perithecium, and cleistothecium, each with its own unique characteristics.

Ascocarps contains millions of embedded asci. Each asci contain four to eight ascospores produced through sexual reproduction. Ascocarps play a role in the life cycle of ascomycete fungi. It helps in the dispersal of spores for reproduction.

The structure of ascocarps vary depending upon different species but they contain these common

• Asci: Asci are sac-like shaped cells within the hymenium where the process of meiosis takes place. This leads to the production of ascospores. These spores remain within the asci until they are discharged
• Ascogenous hyphae: These are hyphae that give rise to the asci. Ascogenous hyphae are often packed within the ascocarp. These provide structural support and help in the development of the reproductive structures.
• Hymenium: It is the fertile layer where the sexual spores called ascospores are produced. The hymenium is located on the inner surface of the ascocarp.
• Pseudoparenchymatous tissue: In some ascocarps, especially in complex forms, there may be additional tissues surrounding the hymenium and asci, providing further support and protection.

Ascocarps are classified into different types based on their structure and mode of development. Some common types are:

• Apothecium
• Cleistothecium
• Perithecium
• Pseudothecium
• Gymnothecium

Now let’s see each of them in detail.

Apothecium

Apothecium are open, cup-shaped ascocarps or fruiting bodies that are found in certain fungi. It mostly contains 3 parts: hymenium, excipulum and hypothecium. The asci or sacs that has spores are found inside the hypothecium. When the apothecia matures the spores are released into the air which also has a main role in spreading of fungi. Morchella is an example of a apothecium.

Cleistothecium

Cleistothecium is a spherical shaped fruiting body found in certain fungi. Cleistothecium is completely closed and do not have any special opening. Its outer wall is made up of pseudoparenchyma cells called the peridium which is covered by hyphae. Inside, the asci, which contain spores, are scattered throughout the flesh. Unlike other fungi, spores in cleistothecia do not release automatically. Instead certain animals may break them and then spore start to disperse. Eurotium exhibits this kind of enclosed fruiting body.

Perithecium

Perithecium is a flask-shaped fruiting body with an opening like a pore through which ascospores are released. The canal is lined with hair-like structures which are called as periphyses. Inside, cylindrical-shaped unitunicate asci are borne on a stalk and these are released through a pore. The asci have a well-developed inner wall originating from the perithecium. Perithecia are commonly found in fungi like Xylaria.

Pseudothecium

Pseudothecium is similar to a perithecium but has a double-wall structure. It expands to take in water and releases spores when dispersal is needed. but, the arrangement of asci inside the hymenium is not well-organized in a pseudothecium. Apple scab is an example of fungi with pseudothecia.

Gymnothecium

Gymnothecium is similar to a cleistothecium, pearl-shaped and completely closed. Inside it contains globose and tender asci. However, the wall of the gymnothecium is made up of hyphae with coils or spines that attract insects. Examples of fungi with gymnothecia include Talaromyces.

The difference between ascocarp and ascus are given below:

In ascocarps both sexual and asexual commonly takes place. In ascocarps frequently asexual reproduction takes place and produces conidiophores that are haploid. Only single gamete is involved here. In sexual reproduction, the ascocarps start after producing filaments called as hyphae. It is present in both male and female.

In the reproductive stage the male releases antheridium and the female has an ascogonium. During the process of fertilization, the antheridium and ascogonium combine in plasmogamy without nuclear fusion.

During the process of karyogamy the two nuclei are fused together. There are thousands of asci that are present in the fruiting body called as ascocarps, these ascospores are released and are involved in developing hyphae, which are used to start developing new mycelia.

Some of the characteristics of Ascocarp are:

• Ascocarps are reproductive structures of the fungi ascomycetes fungi which help in sexual reproduction .
• They are present in different shapes like simple cup like or even multiple layers and complex.
• Ascomycetes can be heterothallic or homothallic which plays a very important role in sexual reproduction.
• Ascocarps can be classified into several types based on their structure and mode of development like Apothecia,Cleistothecia.
• Ascocarps are present in various habitats, including soil, any decaying organic matter, plant tissues, and even on the bodies of some living organisms
• Ascocarps play important roles in ecosystems as they release these spores, like nutrient cycling.

In conclusion, ascocarps are very important part of the life cycle in ascomycete fungi. These serve as the site for sexual reproduction and produce spores. They are diverse in their structures and their reproductive strategies which contribute to the ecological success of ascomycetes in various habitats. Studying the morphology and biology of ascocarps is essential for fungal ecology, pathology, and evolution.

Also Read:

• Ascomycetes – Introduction, Characteristics, Reproduction, Importance
• Kingdom Fungi
• Diagram of Fungi
• Economic Importance of Fungi
• An Overview of Mycorrhizae – Types, Examples, and Importance
• Difference Between Fungi and Lichens

What is the Function of Ascocarp?

The main function of ascocarps is – produce and disperse spores for reproduction and ensuring the survival and spread of the fungal species.

What is an Ascocarp?

An ascocarp is a reproductive structure found in fungi, particularly present in the phylum Ascomycota , where it plays a major role in sexual reproduction.

What are Ascocarps Made of?

Ascocarps are made up of a network of hyphae, which forms a protective structure around the developing spore-producing cells.

How do Spores get out of the Ascocarp?

Spores are released from the ascocarp through structures called asci, which burst open to release spores into the environment.

Is Ascocarp Multicellular or Unicellular?

Ascocarps are typically multicellular structures, these consist of hyphae and are involved in forming a complex fruiting body.