Sexual hybridization and Wide Crosses

Question 1

The product of hybridization

Answer 1

Hybdrid

Question 2

Can occur naturally through agents of pollination. The term hybridization is reserved for crossing between unidentical parents.

Answer 2

Sexual Hybridization

Question 3

Is the most common conventional method of generating a segregating population for selection in breeding flowering species.

Answer 3

Artificial sexual hybridization

Question 4

The basis of hybrid seed development

Answer 4

Hybrid vigor (heterosis)

Question 5

Crossing and backcrossing selected entries with desired traits into adapted stocks

Answer 5

Introgression

Question 6

Is the deliberate crossing of selected parents (controlled pollination)

Answer 6

Artificial hybridization

Question 7

The flowers of the parent selected to be female are prepared for hybridization by removing the anthers, a tedious procedure

Answer 7

Emasculation

Question 8

The process of making a bisexual flower female by removing the male parts or incapacitating them

Answer 8

Emasculation

Question 9

The technique of removing anthers from selected flowers is the most common procedure for the emasculation of flowers (usually using a pair of forceps).

Answer 9

Direct anther emasculation

Question 10

In these methods, the anthers are incapacitated without being removed from the flower. Incapacitation is achieved in several ways.

Answer 10

Indirect anther emasculation

Question 11

Is the assembly of two different genomes into a newly created individual

Answer 11

Immediate effect

Question 12

Genes in the newly constituted hybrid may complement each other to enhance the vigor of the hybrid. The phenomenon of hybrid vigor (heterosis) is exploited in hybrid seed development

Answer 12

Heterosis

Question 13

Hybrids have features that may represent an average of the parental features, or a bias toward the features of one parent, or even new features that are unlike either parent

Answer 13

Transgressive segregation

Question 14

Genetically divergent parents are crossed for recombination of their desirable genes. This way, recombinants that possess both sets of desirable traits will occur in significant numbers in the F2. The F1 contains the maximum number of desirable genes from both parents

Answer 14

Divergent crossing

Question 15

If two elite lines are available that together possess adequate traits, one cross may be all that is needed in the breeding program.

Answer 15

Single cross

Question 16

Desirable traits occur in several cultivars or elite germplasm. In this case, multiple crosses may be required in order to have the opportunity of obtaining recombinants that consist of all the desirable traits.

Answer 16

Three-way cross

Question 17

More genetically broad-based than the single-cross hybrid but is more time consuming to make.

Answer 17

Double cross

Question 18

This method entails making a large number of crosses. Sometimes, a partial diallel is used in which only certain parent combinations are made. The method is tedious to apply to self-pollinated species. Generally, it is a crossing method for genetic studies.

Answer 18

Di-allele cross

Question 19

These are conservative methods of crossing plants

Answer 19

Convergent crossing

Question 20

This kind of crossing involving parents from different species

Answer 20

wide cross

Question 21

When the wide cross involves another species

Answer 21

Interspecific cross

Question 22

When it involves a plant from another genus

Answer 22

Intergeneric cross

Question 23

Plant breeders over the years have introgressed desirable genes into adapted cultivars from sources as close as wild progenitors to distant ones such as different genera

Answer 23

Synthetic (artificial) wide crosses

Question 24

A technique of indirectly crossing two parents that differ in ploidy levels through a transitional or intermediate cross.

Answer 24

Bridge crossing

Question 25

Defined as a population of individuals capable of interbreeding freely with one another but which, because of geographic, reproductive, or other barriers, do not in nature interbreed with members of other species.

Answer 25

Species