LIFE CYCLE OF ALBUGO PDF

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The pciniaresentation describe the life cycle of Pythium, Albugo, Erysiphae, Claviceps, Ustilago, Puccinia. both sexual spores (called oospores) and asexual spores (called sporangia) in a many-stage (polycyclic) disease cycle. infection stag heads oospore productt0n zoo spores. \. SEXUAL c germ1not1~. Oospores -overwintering spores. 8. Figure 8. Life cycle of Albugo candlda.

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Albugo – Wikipedia

Such oospore is called a compound oospore. The sporangia in Lire which are cut off in succession are arranged in a basipetal chain on the sporangiophore.

Minimizing irrigation in cool and moist seasons as well as eliminating windbreaks to allow faster leaf drying can be beneficial.

The first formed sporangium is a aleuriosporangium. In this method after the disappearance of the central globule and the lipid albuggo the contents of oospore assume uniform granular apearance. The likelihood of germination and infection is considerably lower if temperatures deviate ilfe far outside this optimum range. The oospore lifw maturity secretes a two to three layered wall Fig.

The latter is then cut off by a cross wall from the rest of the male hypha B. It has been observed that in C. Each of these metamorhoses into a biflagellate zoosore. The slightly crescent-shaped bulge of the haustorial mother cell known as haustorial initial perforates the host cell wall at the penetration site and protrudes into the lumen of the mesophyll cell to develop into a haustorium.

Finally they settle down on the host, retract the flagella and round off. The two unequal flagella arise from a depression on the concave side. When infection is recognized, systemically infected plant material including culled crops should be completely removed and destroyed. Albugo Albugo candidaon Capsella bursa-pastoris Scientific classification Phylum: After the organization, all the nuclei of the ooplasm, except one, migrate to the periplasm forming pife ring and undergo second mitotic division.

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The second view IS that in the later stages of development all the nuclei in the ooplasm excepting one degenerate and disappear. It is warty or tuberculate. The number lite functional eggs in ooplasm is many. As the second sporangium initial grows to the normal size, it is also delimited by the formation of a basal septum as the first.

This causes the leaf surface to bulge. A few vacuoles appear in its granular cytoplasm. It contains several nuclei usuallybut only one is functional. It has also been observed that A. All nuclei are evenly distributed throughout the cytoplasm Fig. The sexual reproduction is oogamous. It is rich in lipid vesicles and reserve vesicles containing electron dense inclusions reserve globules.

It is elongated and club shaped structure. The single functional female nucleus is attracted towards it and becomes attached to a point near it. The rest of the nuclei disintegrate before fertilization. Common OMRI fungicides include sulphurcopper oxiderosemary oiland azadirachtin products.

This terminal dub-shaped cell is called an antheridium. After reaching a certain stage of maturity, the apical portion of sporangiophore gets swollen and is ready is cut off a sporangium or conidium Fig. These biological forms ire specialised in parasitism, therefore, the phenomenon is called as biological specialization or physiological -specialization.

Albugo: Habitat, Symptoms and Reproduction | Mastigomycotina

On root crops, infected leaf removal either by mowing or plowing prior to harvest will limit the spread of the pathogen during harvest. The distal ones by this time have matured.

Two different views have ccle put forth to explain their mode of development. It separates the terminal oogonium from the rest of the female hypha. It undergoes zygotic meiosis.

Algugo rust is an economically important foliar disease, causing substantial yield losses and eventual death of various crops. The haustorium arises as a lateral outgrowth at the site where the hyphal wall is tightly pressed against the mesophyll cell wall.

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The sex organs develop on the hyphal ends in the intercellular spaces of the deeper tissues of petioles and stems. The asexual reproduction takes place by conidia, condiosporangia or zoosporangia.

The germ tube enters through the stoma and develops into the new mycelium which ramifies in the intercellular spaces of the host tissue.

The taxonomy of this genus is incomplete, but several species are plant pathogens. The outer layer of the oospore wall is comparatively thicker.

Albugo: Habitat, Symptoms and Reproduction | Mastigomycotina

However, at the time of maturity, all nuclei disintegrate, except single functional nucleus Fig. The highly differentiated thick, oospore wall together with the two additional layers constituted by xycle persistent perisperm and the oogonial wall provides protection and the numerous lipid vesicles in the oospore cytoplasm furnish energy for the long dormancy or overwintering by oospores in Albugo. The developing oogonia and antheridia are separated from rest of the mycelium by septa.

The sporangium is smooth, double- walled and rounded. Usually one or two, lkfe more, haustona are seen in the thin peripheral layer of the host cell cytoplasm adjacent to the chloroplasts.

Life Cycle of Albugo (With Diagram) | Oomycetes

At the end of the division one daughter nucleus of each spindle goes to the oosplasm and other in periplasm Fig. Hyphae are intercellular, coenocytic, aseptate and profusely branched Fig.

The parasite ultimately reaches the inflorescence region where it produces the oospores.