In this article we will discuss about the modes of reproduction in morchella which belongs to class ascomycetes.
The vegetative body is an extensively branched mycelium which grows a few inches deep in the substratum and extends over several inches. After growing rapidly for some time mycelial mat begins to be compacted just below the surface of the substratum. The hyphae are septate and the hyphal cells are multinucleate.
Morchella reproduces both asexually and sexually. At the time of asexual reproduction the fruit body, known as the ascocarp (Fig. 181A) is developed for the compacted hyphal mat. It is fleshy stalked and is 8-10 cm. in height. A mature ascocarp has two distinct regions the upper conical spongy structure, known as the pileus or cap, is the fertile region, and the stalk (also known as stipe) bearing the cap is the sterile region.
When the archicarp emerges from the soil, the cap is at first smooth but later on due to irregular growth ridges and furrows are formed and it becomes more or less convoluted in appearance. The stipe as well as the ridges are cream-coloured, but the furrows are brown in colour. A vertical section through the ascocarp (Fig. 181C) shows that the stipe is composed of pseudo-parenchyma cells, and the furrows are lined with the hymenium, or the fertile layer.
The hymenium consists of long cylindrical asci intermingled with paraphyses. In between the cells of the stipe and the hymenium layer, just below the latter, a group of multinucleate cells occur, forming the sub-hymenium. Each ascus contains 8 oval hyaline ascospores, arranged uniseriately.
When the ascospores attain maturity, the ascocarp withers and the epices of asci open by lids through which the ascospores are liberated. Each ascospore falling on a suitable substratum germinates and gives rise to a new mycelium.
In Morchella, sex organs have not yet been discovered. Sexual reproduction takes place by the fusion of nuclei in the vegetative cells.
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