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

The first cross between bread wheat and rye was made by Rimpau in 1890.
In 1888, a partially-fertile hybrid was produced by Wilhelm Rimpau, "Tritosecale Rimpaui Wittmack". Such hybrids only germinate when the chromosomes spontaneously double.
When crossing wheat and rye, wheat is used as the female parent and rye as the male parent (pollen donor).

a. Genotype and phenotype term is given by Johannsen. The terms 'genotype', 'phenotype', and 'gene' originally had a different meaning from that in Modern Synthesis. These terms were coined in the first decade of the twentieth century by the Danish plant physiologist Wilhelm Johannsen.
b. Heterosis term is given by shull. It is the improved or increased function of any biological quality in a hybrid offspring.
c. Recurrent selection is given by Hull in 1945. RECURRENT selection in animal breeding refers to Hull's method of selection for specific combining ability with a tester stock.
d. Overdominance is given by Hull in 1945. Overdominance is a rare condition in genetics where the phenotype of the heterozygote lies outside the phenotypical range of both homozygous parents.

The plant type concept was first introduced by Jennings (1964).
Plant type breeding can be defined as a method of crop improvement which is used to enhance the genetic yield potential through genetic manipulation of Individual plant character.

Two species belonging to the same genus are identical in morphology. Chromosome number and morphology are the structural characteristics that are more useful in distinguishing such species.
Similar DNA sequences, biogeographical features, ecological features, and morphological features of the organisms can be used to rank them in a particular genus.
The chromosome number of each species is different and based on which they can be easily segregated.

Out of the following statement about transposition,
A. Transpose recognizes the insertion sequences are correct.
B. Transposons may be either excised or moved or replicated if correct.
C. Donor and target sites are homologous is incorrect.
D. Transposon discovered by McClintock is correct.
Transposition is a process by which segments of a chromosome are relocated through the genome. A transposable element is a nucleic acid sequence in DNA that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in the duplication of the same genetic material.

The performance of a double cross hybrid (A × C) × (B × D) can be predicted from the average performance of the combination of A × B, A × D, B × C and C × D.
The performance of a double cross hybrid is predicted based on the average performance of the four non-parental single cross hybrids. In this method, the predicted performance of each of the three possible double-cross hybrids would be different.

Strasburger and Hertwig established that character is transmitted from generation to generation through chromosomes.
Oscar Hertwig in 1876 studied fertilization in sea urchins while Strasburger (1877, 1884) made similar observations in plants. Hertwig noted the presence of two nuclei in the fertilized egg and concluded that fertilization involved the fusion of nuclei from two parental gametes.
In 1888 he established that the nuclei of the germ cells of angiosperms undergo meiosis i.e., a reduction division yielding nuclei with half the number of chromosomes of the original nuclei.

The seven traits studied by Mendel were present in 4 chromosomes.
Pea shape (round or wrinkled)
Pea colour (green or yellow)
Pod shape (constricted or inflated)
Pod colour (green or yellow)
Flower colour (purple or white)
Plant size (tall or dwarf)
Position of flowers (axial or terminal)
All these seven contrasting characters of peas were located on 4 different chromosomes.

Sex in plants was discovered by Camerarious.
Rudolf Jakob Camerarius was a German botanist and physician. He is chiefly known for his investigations on the reproductive organs of plants.
It was Camerarius who did experimental work and observed that plants seemed to have sex in some form, and guessed that pollen was the male fertilizing agent. In studying the mulberry, he determined that female plants not near to male (staminate) plants produced fruit but with no seeds.

Multiple factor hypothesis' is given by Nilson Ehle.
A hypothesis to explain quantitative variation by assuming the interaction of a large number of genes (polygenes) each with a small additive effect on the character is a multiple factor hypothesis.
Nilsson-Ehle was a Swedish geneticist working on various cereal crops in 1909. Many of the characters that he examined yielded 3 : 1 ratios in the F2 generation following the cross of two parental strains, consistent with expectations for a single segregating locus with one allele completely dominant over the other.