Genetics And Plant Breeding MCQ Question and Answer | Agriculture MCQ Question

The isolation distance maintained for paddy is 3 m.
Isolation distance is the minimum separation required between two or more varieties of the same species to keep the seed pure. The isolation distance is essential to prevent pollination from unwanted pollen in the case of cross-pollinated and often cross-pollinated species.
Isolation distance should be maintained to avoid varietal contamination of seed. Isolation distance is the distance by which the seed crop is separated from any other variety of the same crop.

The selection process for balanced combination of genes in an individual is called Co adaptation.
Co-adaptation is the process by which two or more species, genes or phenotypic traits undergo adaptation as a pair or group.
This occurs when two or more interacting characteristics undergo natural selection together in response to the same selective pressure or when selective pressures alter one characteristic and consecutively alter the interactive characteristic.

During seed production the methods followed to facilitate flowering and seed production in cabbage are Stump method, the Stump with central core intact method, and Head intact method.
Heads are cut just below the base through sharp knife, keeping the stem with outer whorl of leaves. Beheaded portion of plant is called the stump. This method is termed as stump method.
Stump with central core intact method is improved version of stump method in which heads are chopped on all sides with downward perpendicular cuts in such a way that central core is not damaged.
In head intact method, head is kept intact and only a cross-cut is given to facilitate the emergence of stalk.

Production of DNA from m RNA is conducted by Reverse Transcriptase.
Reverse transcriptase (RT), also known as RNA-dependent DNA polymerase, is a DNA polymerase enzyme that transcribes single-stranded RNA into DNA.
A reverse transcriptase (RT) is an enzyme used to generate complementary DNA (cDNA) from an RNA template, a process termed reverse transcription.
This enzyme can synthesize a double helix DNA once the RNA has been reverse-transcribed in a first step into a single-strand DNA.

The force responsible for the movement of water across the root in the passive absorption of water operates in Leaves.
Passive absorption occurs when the rate of transpiration is typically higher than normal. Rapid evaporation of water from the leaves during transpiration causes a buildup of water in the xylem of the leaves, which results in a buildup of pressure.
Root pressure, in plants, is the force that helps to drive fluids upward into the water-conducting vessels (xylem). It is primarily generated by osmotic pressure in the cells of the roots and can be demonstrated by the exudation of fluid when the stem is cut off just aboveground.

Kranz type of anatomy is found in or is typical of C₄-plants.
C₄ plants include many tropical grasses and are among the world's most important crop species (maize, sugar cane).
The main role, as well as the point of the importance of the Kranz Anatomy, is that it provides the perfect site for CO₂ or carbon dioxide to be concentrated. This happens to surround the RuBisCO. This helps in the continuous fixation of the carbon dioxide that keeps the levels of CO₂ more at any given point in time. The function that makes it all the more significant is that it helps in avoiding photorespiration.

The sudden change in the DNA sequence is Mutation.
A mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA.
The mutation is the ultimate source of all genetic variation, providing the raw material on which evolutionary forces such as natural selection can act.

Pusa Arunima and Pusa Surya are new varieties of mangoes.
Pusa Arunima is a hybrid, derived from the cross between Amrapali and Sensation. The plants are semi-vigorous and are suitable for closer planting (6 m × 6 m). It is a regular bearer and starts bearing after 4^th year of planting. It is suitable for domestic market. It can also be accepted in the international markets, because of its attractive red peel colour, fibreless pulp, mild flavour, medium TSS, excellent sugar: acid blend and long shelf-life. It was released in 2002.
Pusa Surya is a regular bearer variety. Its plants are semi-vigorous. Therefore, it is suitable for closer planting (6 m × 6 m). It is less susceptible to mango malformation in comparison to Amrapali and other commercial cultivars of northern India. It ripens by 3^rd week of July. It is suitable for domestic and international markets. It was released in 2002.

The male sterility controlled by cytoplasmic genes and transmitted only through the female parent is called Cytoplasmic male sterility.
Cytoplasmic male sterility is total or partial male sterility in plants as the result of specific nuclear and mitochondrial interactions.
Male sterility is the failure of plants to produce functional anthers, pollen, or male gametes.
When nuclear restoration of fertility genes is available for a CMS system in any crop, it is cytoplasmic–genetic male sterility; the sterility is manifested by the influence of both nuclear and cytoplasmic genes.

The Source of dwarfing gene in wheat is Norin-10.
Norin 10 wheat is a semi-dwarf wheat cultivar with very large ears that was bred by Gonjiro Inazuka at an experimental station in Iwate Prefecture, Japan.
Its parents were a semi-dwarf Japanese landrace that may have originated in Korea in the 3^rd or 4^th century AD, and two varieties from the USA.
The Rht1 and Rht2 genes have been used in wheat breeding programs worldwide to provide shorter plants with higher yields. Norin 10 was also provided to the International Maize and Wheat Improvement Center in Mexico.