Solanaceae

Quick Summary:

Herbs, vines, shrubs, or trees.

  1. Flowers perfect, radially or bilaterally symmetrical. Sepals 5, fused. Petals 5, fused. Stamens 2, 4, or usually 5, epipetalous, sometimes with anthers connivent (converging or coming together but not fused). Pistil compound, ovary superior, carpels 2.
  2. Fruit a berry or capsule.
  3. Leaves simple or occasionally pinnately lobed to compound, alternate, without stipules.
  4. About 85 genera and more than 2200 species, primarily in tropical America.

The Solanaceae is not a significant family in the flora of B. C., but it is one of the most important in agriculture.

Representatives of this family provide food medicine, poison and ornamental plants. Important crops include Solanum (potato, eggplant), Lycopersicon (tomato), Physalis (tomatillo, ground cherry), Capsicum (red, yellow and green pepers), and Nicotiana (tobacco).

Alkaloids from Atropa (deadly nightshade or belladonna), Hyoscyamus (henbane), Datura, Mandragora (mandrake), and Brunfelsia are used as drugs, hallucinogens, or poisons. Petunia is the most important ornamental member of the Solanaceae in temperate region.

Petunia and Nicotiana

Petunia: Petunias are a common garden plant.
Petunia plant

Petunia plant

Petunia flower

Petunia flower

Petunia flower, side view

Petunia flower, side view

Nicotiana: There are a number of Nicotiana plants grown horticulturally. Species of this genus are also grown for their leaves (tobacco).
Nicotiana plant

Nicotiana plant

The flowers are long and the petals form a tube.
Nicotiana Flower

Nicotiana Flower

To the right is a longitudinal section through the flower. You should be able to identify all of the floral components.
Nicotiana flower, longitudinal section

Nicotiana flower, longitudinal section

This is the fruit (a capsule) of tobacco.
Fruit of tobacco, a capsule

Fruit of tobacco, a capsule

Solanum

Solanum dulcamara (European Bittersweet): This is commonly found along roadsides and “waste lands”. Many of the members of the Solanaceae have large anthers which form a yellow cone in the centre of the flower. The stamens are attached to the purple petals.
Solanum flowers

Solanum flowers

The pollination mechanism of this type of flower is very interesting. The bee hangs upside down and buzzes, generating vibrations which cause the pollen to fall onto the body of the insect. The bees collect the pollen and take it back to the hive where it is fed to the developing larvae. Of course they cannot collect all of the pollen from their body and when they visit another flower the leftover pollen can be deposited on the stigma of the next flower. Notice the filament and stigma protruding from the cone of anthers in the picture below.
Solanum, flower arrangement

Solanum, flower arrangement

The fruits (berries) of this plant look delicious, but are very poisonous.
Solanum, berries

Solanum, berries

Solanum melongea (eggplant) – Flower
Flower of an eggplant

Flower of an eggplant

Solanum crispum (Chilean potato vine)
Chilean potato vine flower

Chilean potato vine flower

Side view of the flower.
chilean potatl flower, side view

Close up, side view

You can see the pores terminating the anther (poricidal dehiscence).
Close up

Close up

Solanum lycopersicon Lycopersicon esculentum (tomato). Not all buzz-pollinated flowers have purple flowers. Corollas come in other colours such as white and yellow.
Tomato flower

Tomato flower

The petals have been removed to reveal the ovary and the sepals.
Ovary and sepals

Ovary and sepals

Fruit (berry) cross-section:
Tomato fruit, cross section

Tomato fruit, cross section

Other members of the Solanaceae

Atropa belledonna:Belladonna has a long history of use by people. It has links to witchcraft; it has chemicals which have been used for their hallucinogenic qualities. These chemicals have other very deadly side effects. We will explore the chemicals further in Unit 4.
Belladonna flower

Belladonna flower

Here you can see the flowers and fruit (berries).
Belladonna flower and fruit

Belladonna flower and fruit

Longitudinal section through a flower.
Belladonna flower, longitudinal section

Belladonna flower, longitudinal section

A close-up of the fruit:
Belladonna fruit

Belladonna fruit

Physalis ixocarpa (Tomatillo): The fruit of this plant is wrapped in the enlarged calyx. It is very popular in Mexican cuisine.
Tomatillo

Tomatillo

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