Structure and development of Haliphthoros milfordensis Vishniac / by Santford V. Overton.
| Author/creator | Overton, Santford V. author. |
| Other author | Bland, Charles E., degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 1979. |
| Description | vi, 123 leaves, 35 leaves of plates : illustrations ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | Light and electron microscope observations were made of zoospore structure, encystment, germination and cleavage in two strains of Haliphthoros milfordensis isolated from gills of the white shrimp, Penaeus setiferus, and from the American lobster, Homarus americanus. Also studied were infection of the brine shrimp, Artemia salina, by H. milfordensis, development of the fungus in the host, and host-parasite interaction. Zoospores of H. milfordensis possess two subapicaliy attached flagella (anterior tinsel, posterior whiplash) as characteristic of the class Oomycetes. Spore encystment begin with flagellar retraction and roundlng-up of the spore, and ends with formation of a spined, trl-laminate wall. Cyst germination is typical of the class and occurs via fracturing of the spined wall. Spcrogenesis is holocarplc but unusual in that spore cleavage is sequential, beginning in the sporangium and ending in the discharge tube. Cleavage is initiated by the coalescing/fusion of vacuoles resulting in cleavage furrows. This is accomplished by separation of cytoplasm from the cell wall due to coalescence of vesicles along the wall. As vacuolar fusion continues, distinct, uninucleate spore initials become recognizable. During infection of A. salina, zoospores of H. milfordensis readily encyst on the exoskeleton of larvae. This is followed by germination, penetration of the exoskeleton by young vegetative hyphae, and growth through the epidermis into the body cavity. An electron-dense material is produced at the host-parasite interface and is likely a response of the shrimp to infection with H. milfordensis. Histolytic activity by the fungus is evident by the numerous vesicles released into the host cytoplasm and by the apparent dissolution of host cytoplasm along the growing hyphal tips. Encapsulation of the fungus by the host is observed occasionally. |
| Local note | Joyner-"Presented to the faculty of the Department of Biology ... in partial fulfillment of the requirements for the degree Master of Science in Biology." |
| General note | Presented to the Faculty of the Department of Biology |
| General note | Advisor: Charles E. Bland |
| Dissertation note | M.S. East Carolina University 1979 |
| Bibliography note | Includes bibliographical references (leaves 120-123). |
| Genre/form | dissertations. |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | Access Content Online | ✔ Available |