Reproduction and Life Cycle
The life cycle of Physarum polycephalum starts with the spores being released from a mature sporangia (a stalk with a round top) and distributed through the air by wind (Renner, 2006); (American Society for Microbiology, 2014). The round, haploid and spiny spores then crack open, and a myxamoeba (a uni-nucleate haploid without a cell wall) is released (Department of Botany University of Hawai'i at Manoa, n.d.). Thus starts the myxamoeba stage. Itbegins taking in food as it moves using amoeboid motion . The myxamoeba will continue to grow and eventually goes through the processes of mitosis and cytokinesis to reproduce and multiply. If the myxamoeba is in the water it can transform into flagellated swarm cells (Department of Botany University of Hawai'i at Manoa, n.d.). The myxamoeba stage will continue as long as there are viable nutrients and favorable environmental conditions. The most favorable conditions are often in the Spring and Autumn, since they are milder more moist times of the year (Renner, 2006). When conditions aren’t favorable, the myxamoeba or swarm cell is protected by the microcyst, a thin layer of cellulose (Department of Botany University of Hawai'i at Manoa, n.d.).
After an adequate number of myxamoeba are formed the gamete stage begins. In this stage the myxamoeba, but mainly the swarm cells, contribute like gametes. For the fusion of the cells, and thus reproduction to occur, they must be from a different population. A zygote is formed after two compatible gametes fuse. The zygote is then divided many times to form the plasmodium, a diploid structure, which is essentially one large cell with many nuclei (Department of Botany University of Hawai'i at Manoa, n.d.).
After an adequate number of myxamoeba are formed the gamete stage begins. In this stage the myxamoeba, but mainly the swarm cells, contribute like gametes. For the fusion of the cells, and thus reproduction to occur, they must be from a different population. A zygote is formed after two compatible gametes fuse. The zygote is then divided many times to form the plasmodium, a diploid structure, which is essentially one large cell with many nuclei (Department of Botany University of Hawai'i at Manoa, n.d.).
Differences Between Cellular and Plasmodial Reproduction
The factors that separate Plasmodial Slime Molds from Cellular Slime Molds have to do with reproduction. The spores of plasmodial molds can be unflagellated or flagellated, the zygote results from two different haploid cells, and the zygote eventually becomes plasmodium ("Slime Molds", 2003).