Lower Fungi, Mycology, Botany

1. REPRODUCTION & HORMONAL
CONTROL IN ACHLYA
Submitted by: Amaturehman

2. CONTENTS
• Reproduction
1. Asexual
2. Sexual
• Infection
• Research Article

3. Reproduction
Both types of reproduction occurs in Achlya
• Asexual Reproduction
• Sexual Reproduction
Causes infection in aquatic ecosystem because
infection on the skin of fishes, amphbians,etc
called Saprolegniosis

4. Asexual Reproduction
• Development of zoosporangia occurs on the tip of hyphae
• Cylindrical, have central vacuole containing mycolaminarin
• During release, the plasma membrane breached and
volume decreases by 10%, reduces the turgor pressure
• Membrane of vacuole contributes to zoospore plasma
membrane, release mycolaminarins into sporangium and
too large to diffuse but osmotically active increase turgor
pressure by allowing the entry of water. This cause the
rapid discharge of auxiliary zoospores
• During discharge, form cluster in the hollow ball on the
mouth
• After encystment the principal zoospores release

5. Zoosporangium in Achlya

6. Sexual Reproduction
• Some are Homothallic (e.g. A. colorata) while some are
Hetrothallic (e.g. A.bisexualis)
• It occurs by the formation of
1. Oogoium
2. Antheridium
Reproduction is controlled by hormones
If certain of isolates are grown together in the same dish,
one stain forming Oogonia and other forming Antheridia
even separated by cellophane membrane or by agar
• First studied by Raper (1939)

11. Male Mycellium Female Mycellium

13. Research Artical
T.C.McMorris and Gooday Work
2016
The sexual reproductive process in Achlya, a widely
distributed genus of saprophytic aquatic fungi, is initiated
and coordinated by the steroid hormones, antheridiol
and the oogoniols. The discovery of these hormones, and
their isolation and structural identification, are reviewed
in this paper. Achlya contains a number of sterols, the
major one being fucosterol, which serves as the
biosynthetic precursor of antheridiol and the oogoniols.
The biosynthesis of the hormones is discussed as well as
some of their specific functions in the organism.

14. Research Artical
J.Thomas and Charles O.Warren Work
2016
The entire sexual reproductive progression in the
heterothallic water mold Achlya ambisexiialis Raper
occurs in the absence of exogenous nutrients. Mated
male and female mycelia, previously grown on a
chemically defined medium, can utilize endogenous
materials for the formation and maturation of sexual
reproductive structures. Under these conditions the
initiating sexual hormone antheridiol, produced by the
female, exerts its morphogenetic effect on male
mycelium in the absence of exogenous nutrient