Heterosis

Q. A scion is grafted to a stock. The quality of fruits produced will be determined by the quality of

1. Stock
2. Scion
3. Both stock and scion
4. External environmental factors

Q.

Hybrid vigour is due to

1. Emasculation

2. Homozygosity

3. Heterozygosity

4. Linkage

Q. The process of cross breeding two different varieties of crop plants each having a desired characteristic, is known as

1. selection
2. hybridisation
3. crossing
4. Introduction

Q. With regards to the assertion and reason, choose the correct option.
Assertion: In case of vegetatively propagated crops, pure line selection is not required.
Reason: Hybrid vigour is a property of vegetatively propagated plants.

1. Assertion is true but the reason is false
2. Both the assertion and reason are true and the reason is the correct explanation for the assertion.
3. Both the assertion and reason are true but the reason is not the correct explanation of the assertion.
4. Both the assertion and reason are false.

Q.

The species of originally grown in India was

Q. With regards to the assertion and reason, choose the correct option.
Assertion: In case of vegetatively propagated crops, pure line selection is not required.
Reason: Hybrid vigour is a property of vegetatively propagated plants.

1. Both the assertion and reason are true and the reason is the correct explanation for the assertion.
2. Both the assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but the reason is false
4. Both the assertion and reason are false.

Q. I have four pure lines of plants - Line 1 - high yielding ; Line 2 - disease resistant; Line 3 - disease resistant , medium yield; Line 4 - High yielding, susceptible to disease. Which combination of these lines will lead to heterosis in the F1 hybrid?

1. Line 1 and Line 2
2. Line 3 and Line 4
3. Line 1 and Line 3
4. Line 2 and Line 3

Q. Test cross is a cross between

1. All the above
2. Hybrid $\times$ Dominant parent (Tt $\times$ TT)
3. Hybrid $\times$ Recessive parent (Tt $\times$ tt)
4. Hybrid $\times$ Hybrid (Tt $\times$ Tt)

Q.

in maize, hybrid vigour is exploited by a) bombarding the seeds with the dna b) crossing of two inbred parental lines c)harvesting seeds frm the most productive plant d) inducing mutations?

Q. In maize, hybrid vigor is exploited by

1. Bombarding the seeds with DNA
2. Harvesting seeds from the most productive plants
3. Crossing of two inbred parental lines
4. Inducing mutations

Q. Phenomenon in which hybrids acquire the superior characteristics of both the parents is known as

1. Heterosis
2. Hybrid vigour
3. Inbreeding
4. Superiority

Q. Hybrid vigour is mostly due to

1. Homozygosity of the pure characters
2. Superiority of all the genes
3. Mixing of the male and the female cytoplasm
4. Heterozygosity