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

Self Incompatibility is controlled by two genes found in Gramineae.
Self-incompatibility (SI) is defined as the inability to produce zygotes after self-pollination in a fertile hermaphrodite plant, which has stamens and pistils in the same flower. This structural organization of the hermaphrodite flower increases the risk of self-pollination, leading to low genetic diversity.
SI is controlled by genes at the S-locus. The S-LOCUS RECEPTOR KINASE (SRK) gene encodes a serine/threonine kinase localized in the plasma membrane of the stigma epidermis.

The polar nucleus in embryosac is Diploid.
There are seven cells in the embryo sac. These include three antipodal cells, one central cell (formed by the fusion of 2 polar nuclei), two synergid cells and one egg cell.
Of the two polar nuclei present in the central cell, one is derived from the micropylar end and the other from the chalazal end.
The cell contains two polar nuclei which often fuse to form a single diploid secondary or fusion nucleus.

During meiosis, the chromosome number is Halved.
In meiosis, a cell containing a diploid number of chromosomes is converted into four cells, each having a haploid number of chromosomes.
In human cells undergoing meiosis, for instance, a cell containing 46 chromosomes yields four cells, each with 23 chromosomes.

The seed multiplication rate for Ragi is 420.
The seed Multiplication Ratio is the number of seeds to be produced from a single seed when it is sown and harvested.
At the time of the release of a variety, a small quantity of seed normally known as nucleus seed is available with the plant breeder.

A number of meiosis required to produce 102 pollen grains is 26.
Meiosis division leads to the formation of 4 daughter cells, therefore a pollen grain on meiotic division produces 4 pollen grains.
Thus, 25 pollen grains produce 100 new pollen grains, but according to the question, the required number of pollen is 102, therefore 26 meiotic divisions will produce the required number of pollen grains.

Cytoplasmic and genetic male sterility is exploited in hybrid seed production.
Cytoplasmic male sterility (CMS), a condition under which a plant is unable to produce functional pollen, is widespread among higher plants. CMS systems represent a valuable tool in the production of hybrid seeds in self-pollinating crop species, including maize, rice, cotton and several vegetable crops.
Genetic male sterility (GMS) has emerged as an ideal tool to accelerate hybrid breeding. Male sterility is generally characterized by the impairment of male reproductive development as a result of underlying genetic causes and leads to the malformation of male gametes and/or pollen.

Gregor Mendel, known as the father of genetics, presented his groundbreaking work on inheritance in pea plants in the year 1865.

He delivered his paper titled "Experiments on Plant Hybridization" to the Natural History Society of Brünn in two meetings held on February 8 and March 8, 1865.

Although the paper was published in 1866, the actual presentation was made in 1865.

This work laid the foundation for the modern science of genetics.

Hence, the correct answer is 1865.

Molybdenum plays a major role in Nitrogen fixation.
Mo is the component of meta-protein nitrogenase which helps the process of biological nitrogen fixation and acts as an essential component needed for N bacteria metabolism. The nitrogenase enzyme needs the Mo element in the process of its metabolism, which acts as an electron carrier between the oxidized and reduction stages.

The term recurrent selection was coined by Hull in 1945.
He proposed a breeding method that was termed "recurrent selection for specific combining ability."
Recurrent selection means repeated cycles of selection and breeding aimed at the gradual genetic improvement of a few key traits in a single species. The benefits of breeding are cumulative in that each cycle or generation of improvement builds upon advances made in prior generations.

The terms horizontal resistance and vertical resistance were first used by Van Der Plank in 1963.
The term vertical resistance, used commonly in the context of plant selection, was first used by J. E. Vanderplank to describe single-gene resistance. This contrasted with the term horizontal resistance which was used to describe many-gene resistance.
Genetic resistance that is effective at preventing successful attack only by certain races of a pathogen is called specific or vertical resistance, whereas resistance that is effective at preventing successful attack by all races of a pathogen is called general or horizontal resistance.