Hybridization in Plants

Definition of Hybridization

The process of formation of offspring as a result of interbreeding between two animals or plants of the same taxa or can be of different taxa is called hybridization. The organism which is produced as a result of interbreeding is called hybrid.

Types of Hybrids

There are three types of hybrids.

Inter-specific hybrids

Hybrids between different species within the same genus are called interspecific hybrids or crosses.

Inter-specific hybrids are bred by mating two species, normally from within the same genus. The offspring display characteristics and traits of both parents. The offspring of an inter-specific cross may be sterile.

Sterility is caused in some species due to the different number of chromosomes; the two species have.

Intra-specific hybrids

Hybrids formed as a result of interbreeding between different sub-species within a species are called Intra-specific hybrids.

Inter-generic hybrids

Hybrids formed from the interbreeding of organisms between different genera are called intergeneric hybrids.

Hybrid Vigor

Plant hybrids are often stronger than either parent variety. This phenomenon is known as hybrid vigor or heterosis or heterozygote advantage. Plant breeders make use of a number of techniques to produce hybrids.

Hybrid Name

In botanical nomenclature, a hybrid may be given a hybrid name. hybrid name is a special kind of botanical name. the ICBN (International Code of Botanical Nomenclature) provides the following options in dealing with the hybrid.

1. A hybrid may get a normal botanical name; this will usually be the option of choice for naturally occurring hybrids.
2. A hybrid may also be indicated by a formula listing the parents. Such a formula uses the multiplication sign “x” to link the parents.
3. A hybrid name is reserved for horticulturally arising hybrids and artificial and/ or forced hybrids. A hybrid name is indicated by a multiplication sign “x” placed before the name or epithet, as the case may be.

A hybrid name is a botanical name and is treated like the other botanical names. The multiplication sign is not the part of the actual name. this means that, say, Drosera x anglica for nomenclatural purposes is to be treated as Drosera anglica.

Purpose of Plant hybridization

1. Hybrid plants are the plants that are created manually, so they can have useful characteristics.
2. Plant species hybridize a lot more readily than animal species and they are generally fertile.

• Plant hybrids are often created to get different characteristics and traits from both parents.

1. It improves the production of seeds and fruits.
2. Hybridization creates multiple variations across genes or gene combinations.
3. Successful hybrids can evolve into new species within 50 – 60 generations. This can lead some scientists to speculate that life is a genetic continuum rather than a series of self-contained species.

Some Hybrid Plants

Some of the hybrid plants are given below:

• Leyland Cypress

A hybrid between Monterey Cypress and Nootka Cypress.

• Limequat

A hybrid between lime and kumquat.

• Loganberry

A hybrid between raspberry and blackberry.

• London Plane

A hybrid between Oriental plane and American plane (American sycamore).

• Peppermint

A hybrid between spearmint and water mint.

• Tangelo

A hybrid of a Mandarin orange and a pomelo grapefruit which may have been developed in Asia about 3500 years ago.

• Triticale

A wheat-rye hybrid.

• Wheat

Most modern and ancient wheat breeds are hybrids.