Plant Pathology MCQ Question and Answer | Agriculture MCQ Question

Pollination by insects is Entomophily.
Entomophily or insect pollination is a form of pollination whereby pollen of plants is distributed by insects.
Flowers pollinated by insects typically advertise themselves with bright colours, sometimes with conspicuous patterns leading to rewards of pollen and nectar; they also have an attractive scent which in some cases mimics insect pheromones.

Pythium is the pathogen among the following options that have lemon-shaped conidia.
Pythium is a genus of parasitic oomycetes. They were formerly classified as fungi.
The conidia are thick-walled, round to lemon-shaped, and rough to spiny with hyaline or brown cell walls.

The innermost wall layer of the pollen sac is the tapetum. Its function is in Nutrition.
The tapetum is a specialized layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporogenous tissue and the anther wall.
Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.

Phyllactinia of the powdery fungi has endophytic mycelium with bulbous appendages at the base.
Phyllactinia is another powdery mildew genus occurring on Fraxinus species worldwide. This genus is characterized by having a semi-endoparasitic habit with both endophytic and superficial mycelia formed in and on host leaves.
P. guttata is characterized by large ascomata, long narrow pointed appendages with bulbous swellings at the base, and 2- or 3-spored asci with large ascospores; the ascomata also have gelatinous cells with tufts of hyphae somewhat resembling hairs.

Teliospores of rust have germ pores in two numbers.
Teliospore (sometimes called teleutospore) is the thick-walled resting spore of some fungi (rusts and smuts), from which the basidium arises.
Teliospores consist of dikaryotic cells. As the teliospore cells germinate, the nuclei undergo karyogamy and thereafter meiosis, giving rise to a four-celled basidium with haploid basidiospores.

The sensitivity of PCR is 1-10 pg/l.
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it.
PCR was invented in 1983 by the American biochemist Kary Mullis at Cetus Corporation. The high sensitivity of PCR permits virus detection soon after infection and even before the onset of the disease.
PCR assays can be performed directly on genomic DNA samples to detect translocation-specific malignant cells at a sensitivity that is at least 10,000 fold higher than that of other methods.

Beadle and Tatum proposed the 'one gene-one enzyme-one chemical reaction' theory.
The one gene-one enzyme hypothesis is the idea that genes act through the production of enzymes, with each gene responsible for producing a single enzyme that in turn affects a single step in a metabolic pathway.
The concept was proposed by George Beadle and Edward Tatum in an influential 1941 paperon genetic mutations in the mold Neurospora crassa and subsequently was dubbed the "one gene-one enzyme hypothesis" by their collaborator Norman Horowitz.

Fungi and Disease in Plants' were written in 1918 by E. J. Butler.
Sir Edwin John Butler was an Irish mycologist and plant pathologist. He became the Imperial Mycologist in India and later the first director of the Imperial Bureau of Mycology in England.
During his twenty years in India, he began large-scale surveys on fungi and plant pathology and published the landmark book Fungi and Disease in Plants: An Introduction to the Diseases of Field and Plantation Crops, especially those of India and the East (1918) and has been called the Father of Mycology and Plant Pathology in India.

Mercuric chloride is used as a Surface sterilant.
Mercuric Chloride is an odorless, white crystal or powder. Mercuric chloride is used as a disinfectant to remove surface microorganisms. The result showed that the increasing concentration of mercuric chloride inhibits the growth of bacteria efficiently with increasing contact time.

Cross pollination is Allogamy.
Allogamy or cross-fertilization is the fertilization of an ovum from one individual with the spermatozoa of another.
In plants, allogamy is used specifically to mean the use of pollen from one plant to fertilize the flower of another plant and is usually synonymous with the term "cross-fertilization" or "cross-pollination" (outcrossing).