The pciniaresentation describe the life cycle of Pythium, Albugo, Erysiphae, Claviceps, Ustilago, Puccinia. Albugo is a genus of plant-parasitic oomycetes. Those are not true fungi ( Eumycota), although Albugo candida, on Capsella bursa-pastoris oospores) and asexual spores (called sporangia) in a many-stage (polycyclic) disease cycle . Albugo candida commonly known as white rust, is a species of oomycete in the family 1 Distribution; 2 Hosts; 3 Symptoms; 4 Life-cycle; 5 References; 6 Further This pathogen infects plants in the family Brassicaceae; the growth stages.

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Life Cycle of Albugo (With Diagram) | Oomycetes

Candida attacks only the members of family Brassicaceae Cruciferae but not others. The disease caused by Albugo is commonly known as white rust because it appears in the form of shiny, white, smooth irregular patches pustules or blisters on the leaves, stems and other aerial parts of the plant.

The development of sex organs within the host tissue is externally indicated by hypertrophy and distoration in shape in the particular organ. It arises as a globular enlargement of the tip of the female hypha. On root crops, infected leaf removal either by mowing or plowing prior to harvest will limit the spread of the pathogen during harvest. Septa remain suppressed in the actively growing hyphae but appear to separate reproductive structures and to seal off injured parts.

Khan did not notice any increase in length of the sporangiophore during sporangia formation nor did he observe any annellations on the sporangiophore surface. White rust can be a devastating disease on many important agricultural crops throughout the world. One functional male nucleus transfers through the tube, reaches the egg, fuses with the female nucleus and the rest of the nuclei of the antheridium degenerate.


After the completion of the basal septum and conversion of candidw initial into a full-fledged sporangium, a new sporangium initial grows as a bud from the sporogenous locus B. The process is repeated resulting in a chain of sporangia.

At the point of contact of antheridium with the oogonium, the walls become very thin. When the oomycete has successfully invaded the host plant, it grows and continues to reproduce.

Successively the sporangia develop by constriction method, in basigenous chains. The zoospores are uninucleate, slightly concavo-convex and biflagellate. After attaining a certain age of maturity, it produces a dense mat like growth just beneath the epidermis of the host Fig.

White rust is an economically important foliar disease, causing substantial yield losses canrida eventual death of various crops. The paragynous antheridium comes in direct contact with the oogonium at the side C.

Oospore is the only diploid structure in the life cycle. On removing or displacing the attached antheridium Tewan and Skoropad observed a clear hole surrounded by some liff material. Soon the encysted zoospore cyst puts out a germ tube E which enters the host tissue through a stoma.

The antheridium develops on the terminal end of another hypha lying very close to the oogonium. The nuclei divided mitotically and increase in number as the oogonium lifw towards maturity. It penetrates through receptive papilla, oogonial wall and periplasm and finally reaches upto the ooplasm Fig.


Host species include most if not all plants in the Brassicaceae family, common agricultural weeds, and those specified below.

Albugo| Life cycle| White Rust| Peronosporales|

The chains of sporangia lengthen and press on the epidermis above. It indicates the establishment of a compatible functional host-parasite relationship. Here’s how it works: Between the haustorium and the host plasma membrane is an encapsulation.

At the end of the division one daughter nucleus of each spindle goes to the oosplasm and other in periplasm Fig.

Probably the two earlier of these divisions constitute meiosis. When liberated, the sporangia inside the pustules are spread by wind, rain, and insects. The single functional female nucleus is attracted towards it and becomes attached to a point near it.

White rust plant diseases caused by Albugo fungal-like pathogens should not be confused cyxle White Pine Blister RustChrysanthemum white rust or any fungal rustsall of which are lire plant diseases but have completely different symptoms and causal pathogens.

The sporangia are transferred from one place to another by various agencies such as wind, insects, water, etc. Probably the septum seen at the apex of each younger sporangium thickens on both sides to form a connective between the successive sporangia in the chain.