The disease produced by Albugo on the crucifers is
White Rust of Crucifers. White rust, also called white blisters, is a fungal disease caused by the fungus Albugo candida, which affects cruciferous plants that include vegetables such as kale, Brussels sprouts, cauliflower, broccoli and cabbage. Brassica weeds are also attacked.
The mycelium of the albugo is
Mycelium of Albugo: It is well developed and consists of branched, aseptate, coenocytic hyphae. The hyphae live and ramify in the intercellular spaces of the susceptible host tissue.
From one crop to next another; the infection of Albugo reaches in the form of
The infection is spread by Albugo is by oospore- infected seeds or by mechanical movement of sporangia. Oospores are light in weight and can be blown by wind.
The male gamete in albugo reaches to the female gamete by
This pollen tube carries a male gamete to meet a female gamete in an ovule. In a process called fertilisation, the two gametes join and their chromosomes combine, so that the fertilised cell contains a normal complement of chromosomes, with some from each parent flower.
Which of the following sets of conditions favour rapid spread of white rust disease
Favorable conditions for the dispersal and consequent infection of white rust from diseased to healthy plants are most common in the autumn and spring seasons. This pathogen prefers cool, moist conditions for the spread and formation of new infections. Conversely, it rarely infects in warm, dry conditions.
Albugo bliti attacks on
Known on sweet potato and species of the Capparidaceae and Amaranthaceae. Some strains may attack a few closely related species of hosts in some species of Albugo. Disease Cycle. Most species overwinter by means of mycelium in perennial parts of overwintering hosts and oospores in debris of infected plant parts.
Haustoria of albugo are
Stalking is unwanted or repeated surveillance by an individual or group towards another person. Stalking behaviors are interrelated to harassment and intimidation and may include following the victim in person or monitoring them.
Sexual reproduction in albugo produced which type of symptoms on host plant
After fertilization coenocentrum in albugo
Thereafter the fertilisation tube collapes but persists and the coenocentrum vanishes.
Haustoria of Albugo is
Viruses are similar to albugo in
An obligate parasite or holoparasite is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host. If an obligate parasite cannot obtain a host it will fail to reproduce. This is opposed to a facultative parasite, which can act as a parasite but does not rely on its host to continue its life-cycle. Obligate parasites have evolved a variety of parasitic strategies to exploit their hosts. Holoparasites and some hemiparasites are obligate.
Resting oospore of A.candida contains
Which of the following is the source of primary infection by Albugo candida
The sporangia inside the pustules are spread by wind, rain, soil and insects. After landing on a susceptible plant, each sporangium gives rise to about six zoospores which, under suitable conditions of moisture and light, form germ tube which invade the plant’s tissues. Thick walled sexual spores, called oospores are produced which germinate, producing either vesicles inside the plant tissue, exist tubes with vesicles at the tip, or germ tubes. Further zoospores develops inside the vesicles. The infection is spread by either soil borne oospores or oospore- infected seed or by mechanical movement of sporangia.
Albugo is an obligate parasite which attacks mostly crucifers like turnip, mustard, radish, cabbage, cauliflower etc. 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. Its thallus is eucarpic and mycelial. Hyphae are intercellular, coenocytic, aseptate and profusely branched.
Which stain and mount are generally used for fungi
Lactophenol Cotton Blue Solution is a mounting medium and staining agent used in the preparation of slides for microscopic examination of fungi. Fungal elements are stained intensely blue.
Conidia of Albugo-candida collected from mustard are not infective to raddish leaves because
In Albugo, it has been observed that a species for e.g., A. Candida attacks only the members of family Brassicaceae (Cruciferae) but not others. It has also been observed that A. Candida infects only one host e.g., Brassica but it does not infect the other host i.e., radish. This means that the A. Candida obtained from different host are not the same and therefore, have to be named differently.
Study of secondary infection is called
A secondary infection can occur when a different infection, known as the primary infection, makes a person more susceptible to disease. It is called a secondary infection because it occurs either after or because of another infection. In other words, it is secondary to that infection.
Bordeaux mixture is first fugicide, is discovered by
This book covers the discovery and development of the Bordeaux mixture by Pierre Marie Alexis Millardet. This discovery was significant in the history of plant pathogen control. The Bordeaux mixture was the first fungicide to be widely used throughout the world.
How many nuclei is/are found in conidia of Albugo
The terminal end of the sporangiophore becomes constricted and sporangium contains 5-8 nuclei and cytoplasm. Successively the sporangia develop by constriction method, in basigenous chains.
At what stage septa are formed in Albugo
It pushes the newly-formed sporangium upward. Thus only one sporangium is formed at a time. As the second sporangium initial grows to the normal size, it is also delimited by the formation of a basal septum as the first. The repetition of the process results in the formation of a basipetal chain of sporangia.
Albugo is found
Albugo candida commonly known as white rust, is a species of oomycete in the family Albuginaceae. It is on the leaves of a living plant sometimes called a fungus, but in fact forms part of a distinct lineage of fungus-like microorganisms, Oomycetes, commonly known as water moulds.
Which part of the plant is not infected by Albugo
Root is not affected by albugo,because the disease caused by Albugo is commonly known as white rust which appears in the form of shiny, white, smooth irregular patches (pustules) or blisters on the leaves, stems and other aerial parts of the plant.
Most common method of asexual reproduction in Albugo, by
Albugo produces conidiosporangia
Asexual reproduction occurs in most Oomycetes by the formation of a structure called a sporangium (pl. In Albugo, an unbranched sporangiophore produces a chain of sporangia. Clusters of sporangia beneath the plant epidermis form blisters that rupture as sporangia are released.
The order of development of conidia in Albugo is
Conidia usually develop either singly or in chains on a particular locus directly upon the vegetative hyphae or upon hyphal stalks or branches called conidiophores. Spores play an important role in the life cycle of fungi acting as dispersal or survival.
The flagella on the zoospores of Albugo are
Zoospores of Albugo are uninucleated, reniform or bean-shaped and biflagellated. Flagella are located on the lateral side of zoospore which are unequal in length. Out of them small the hairy flagellum is called Tinsel or Pantonematic or Flimmergersa.
Albugo draws nutrition from its host by
In what form of the food is stored in the mycelium of Albugo
Reserve food material is in the form of oil drops and glycogen bodies. Some mycelium is intracellular in the form of knob-like haustoria for the absorption of food material from the host cells.
Which structure of Albugo exhibits symptoms of white rust disease
Albugo mycelium can reproduce (a) Sexually (b) Asexually (c) Vagetatively
The Albuginaceae reproduce by producing both sexual spores (called oospores) and asexual spores (called sporangia) in a many-stage (polycyclic) disease cycle.The liberated sporangia in turn can either germinate directly with a germ tube or begin to produce biflagellate motile zoospores.
The conidiophores of Albugo are
Asexual Reproduction of Albugo: It takes place by conidia or conidiosporangia. Mycelium below the epidermis gives off many erect, short, unbranched, club-shaped hyphae called conidiophores.
Secondary infection of white rust could be controlled by
Bordeaux mixture (also called Bordo Mix) is a mixture of copper(II) sulphate (CuSO4) and slaked lime (Ca(OH)2) used as a fungicide. It is used in vineyards, fruit-farms and gardens to prevent infestations of downy mildew, powdery mildew and other fungi.
Female Gametangium of Albugo is called :
Produced in special containers called gametangia, which are multicellular. In oogamy, the male gametangia are called antheridia and the female oogonia or archegonia. A female gametangium with a sterile cellular jacket is called an archegonium, although, like.
The gametes of Albugo are
Like all the other species in its genus, Albugo occidentalis is an oomycete. The survival non-flagellated structure is an oospore, which is the result of the karyogamy of two haploid gametes (the oogonium and antheridium). Asexual propagation of Albugo occidentalis occurs via the production of sporangia on sporangiophores.
The gametes of Albugo are
Like all the other species in its genus, Albugo occidentalis is an oomycete. The survival structure is an oospore, which is the result of the karyogamy of two haploid gametes (the oogonium and antheridium). Asexual propagation of Albugo occidentalis occurs via the production of sporangia on sporangiophores.
Which stage in the life cycle of Albugo candida is not coenocytic
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria and fungi to propagate themselves.
The flagella on the zoospore of Albugo are
Structure of zoospore: The liberated zoospore is a biflagellate, uninucleate structure which is reniform in shape. The two unequal flagella arise from a depression on the concave side. The shorter flagellum is of tinsel type and the longer one of whiplash type.
Hypertrophy of floral parts in a cruciferous plant is caused by
The exterior development of higher plants indicated by hypertrophy. Both antheridium and oogonium are formed of hyphal branches (primary branches).
To cause infection, the germ tube enters through
Stomatal droplets induce the germ tubes of leaf-invading fungi to pass into the stomata and infect the leaf. The droplets may be retracted, and draw bacteria from the leaf surface into sub-sto- matal cavities and intercellular spaces.
An excessive enlargement of a diseased organ due to an increase in the number of its cells is called
Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number.
Which of the following is the symptom of white rust disease of crucifers
The disease in association with downy mildew disease of crucifers caused by Peronospora parasitica cause severe damage to the crop. Symptoms of White Rust Disease: .Symptoms may appear as a result of two types of infection: Local and Systemic.
Which of the following produced non-motile gamete -
Ulothrix is a species of filamentous green algae that reproduces vegetatively by fragmentation. The asexual reproduction takes place with the help of aplanospores which are non-motile resting spores and zoospores. The biflagellate gametes are responsible for its sexual reproduction.
Sexual reproduction in Albugo is
The sexual reproduction is oogamous. The sex organs develop on the hyphal ends in the intercellular spaces of the deeper tissues of petioles and stems.
What holds the conidia together into a chain in Cystopus/Albugo -
Albugo belongs to
Albugo is a genus of plant-parasitic oomycetes. Those are not true fungi (Eumycota), although many discussions of this organism still treat it as a fungus. The taxonomy of this genus is incomplete, but several species are plant pathogens.