Chapter 5Chapter 5

Plant ReproductionPlant Reproduction

When organisms duplicate When organisms duplicate themselves, the process is termed themselves, the process is termed reproduction.reproduction.

When production is deliberately When production is deliberately controlled and manipulated, it controlled and manipulated, it becomes propagation.becomes propagation.

The reproduction of plants through the The reproduction of plants through the formation of seeds is called sexual formation of seeds is called sexual reproduction.reproduction.

Asexual reproduction is a vegetative Asexual reproduction is a vegetative process that eliminates genetic process that eliminates genetic variation. variation.

Mitosis is the normal division of a cell Mitosis is the normal division of a cell nucleus that occurs as a plant grows, nucleus that occurs as a plant grows, enlarging from embryo to maturity.enlarging from embryo to maturity.

In a natural world, plants reproduce In a natural world, plants reproduce both sexually and asexually.both sexually and asexually.

Sexual propagation utilizes seeds.Sexual propagation utilizes seeds.

Scarification is the breaking of a seed Scarification is the breaking of a seed coat otherwise impervious to water coat otherwise impervious to water to permit water uptake by the to permit water uptake by the embryo.embryo.

Stratification is the exposure of the Stratification is the exposure of the seeds to low temperatures.seeds to low temperatures.

Different methods of Scarification

When many plants are reproduced asexually When many plants are reproduced asexually from a single plant, the group of new plants is from a single plant, the group of new plants is termed a clone.termed a clone.

Plants of horticultural importance that are Plants of horticultural importance that are propagated almost totally by asexual means propagated almost totally by asexual means are termed clonal varieties. They are a type of are termed clonal varieties. They are a type of cultivar.cultivar.

Runners are stems that grow along the Runners are stems that grow along the ground and form new plants at one or more of ground and form new plants at one or more of their nodes.their nodes.

Stolons are aerial shoots that take root after Stolons are aerial shoots that take root after coming into contact with the soil.coming into contact with the soil.

Certain plants produce new shoots Certain plants produce new shoots from adventitious buds that develop from adventitious buds that develop on the roots called sucker shoots.on the roots called sucker shoots.

In layering, roots develop on a stem In layering, roots develop on a stem that is still attached to the parent that is still attached to the parent plant.plant.

Propagation by stem cuttings is the Propagation by stem cuttings is the most common means of most common means of

reproducing plants asexuallyreproducing plants asexually..

A plants external appearance is also A plants external appearance is also know as its phenotype.know as its phenotype.

A plants genetic composition is also A plants genetic composition is also know as its genotype.know as its genotype.

Gregor Mendel took two strains of Gregor Mendel took two strains of garden pea’s that were notably garden pea’s that were notably different in height and conducted different in height and conducted experiments on them.experiments on them.

When the sexual reproduction When the sexual reproduction process is controlled by the process is controlled by the deliberate actions of human beings, deliberate actions of human beings, plant breeding results and a plant breeding results and a specialized science, plant genetics, specialized science, plant genetics, takes effect.takes effect.

Mutations are spontaneous changes Mutations are spontaneous changes in the genetic structure of a plant.in the genetic structure of a plant.

Different types of mutations

Asexual propagation Asexual propagation techniques:techniques:

RunnersRunners StolonsStolons Sucker shootsSucker shoots LayeringLayering graftinggrafting