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

The first interspecific cross between carnation and sweet William species of Dianthus was made up by Thomas Fairchild (1717).
Thomas Fairchild an Englishman 1717 produced an interspecific cross between Sweet William (Dianthus barbatus L.) as female and Carnation (Dianthus caryophyllus) as the pollen parent and the product was known as Fairchild's Sweet William (also called Fairchild's Mule), which was sterile.

A virus-free clone from a virus infected plant can be obtained by Meristem culture.
Meristem culture is a plant tissue culture technique in which a plant's fastest growing tissue is cultured, and it is very helpful to produce virus-free plants, as the rate of meristem growth is always higher than virus cell to cell transmission.

Term heterosis was introduced by Shull (1914).
Heterosis, hybrid vigour, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents.
In proposing the term heterosis to replace the older term heterozygosis, G. H. Shull aimed to avoid limiting the term to the effects that can be explained by heterozygosity in Mendelian inheritance.

If a dihybrid is a test crossed, the phenotype ratio of progeny will be 1: 1 : 1 : 1.
Dihybrid test crossing is an experimental cross in which we took one parent from the F1 generation with a heterozygous condition of two traits and another parent in double homozygous condition which will produce different types of gametes which will further fertilise to form new individuals.

The chemical mutagens usually induce Gene mutation.
Chemical mutagens work mostly by inducing point mutations. Point mutations occur when a single base pair of a gene is changed. These changes are classified as transitions or transversions.
Mutations can occur through alterations of single bases in the DNA, or by loss or rearrangement of large sections of DNA.

a. Polytene chromosome with numerous chromosomes - Polytene chromosomes are large chromosomes that have thousands of DNA strands. They provide a high level of function in certain tissues such as the salivary glands of insects.
b. Lampbrush chromosome is oocytes - Lampbrush chromosomes (LBCs) are transcriptionally active chromosomes found in the germinal vesicle (GV) of large oocytes of many vertebrate and invertebrate animals.
c. Aerocentric chromosome is centromere near one end - Acrocentric chromosomes are defined as having the centromere near and at the end of the chromosome.
d. Sat chromosome is with a satellite - The satellite at metaphase appears to be attached to the chromosomes by a thread of chromatin. In addition to the centromere, one or more secondary constrictions can be observed in some chromosomes at metaphase. These chromosomes are called satellite chromosomes.

Aflatoxins are produced by fungi.
Aflatoxins are a family of toxins produced by certain fungi that are found on crops such as maize (corn), peanuts, cottonseed, and tree nuts.
The main fungi that produce aflatoxins are Aspergillus flavus and Aspergillus parasiticus, which are abundant in warm and humid regions of the world.

In maize, cross pollination occurs due to Protandry.
When the pistil matures before anthers, it is called protogyny such as in pearl millet. When anthers mature before the pistil, it is known as protandry.
Protandry occurs in small, stable groups with essentially a monogamous relationship between one pair that reproduces. The largest males change sex, becoming females, and large females produce the greatest number of eggs.

The legumes have flower Diadelphous.
Diadelphous is having its stamens fused at least partly by the filaments so that they form two separate bundles, or a bundle and a lone separate stamen.
Each flower consists of five petals: a large banner, two lateral wings, and a keel formed by two fused petals. The keel petals enclose the 9 stamens (androecium) and pistil (gynoecium).

The The M phase is the shortest phase during the cell cycle.
M phase is the period of actual nuclear and cell division during which the duplicated chromosomes are divided equally between two progeny cells.
Cell division occurs during M phase, which consists of nuclear division (mitosis) followed by cytoplasmic division (cytokinesis). It includes several stages: prophase, metaphase, anaphase and telophase. Cytokinesis is another process that runs during telophase and it leads to the splitting of the cytoplasm.