Horticulture Guruji
Exercise 6
To study the morphological characters of Solanaceae crops
Solanaceae is a family of angiosperm plants. It is also known as the ‘potato family’. It is widely distributed in tropical, subtropical, and temperate regions throughout the world. It includes many spices, medicinal plants, vegetable crops, etc. Vegetables like potato, tomato, capsicum, and brinjal are included in the Solanaceae family.
Floral formula
A floral formula is a symbolic representation of the various floral parts, their number, arrangement pattern, and how they are related. The general floral formula of the Solanaceae family is as follows:
Here the symbols represent:
|
⊕ |
Actinomorphic (radial symmetry) |
|
⚥ |
Bisexual |
|
K(5) |
Calyx – 5 sepals, gamosepalous (united) |
|
C(5) |
Corolla – 5 petals, gamopetalous |
|
A5 |
Androecium – 5 stamens, polyandrous (free), epipetalous (attached to petals) |
|
G(2) |
Gynoecium – bi-carpellary, syncarpous (united), superior ovary |
Floral Diagram
1. Vegetative Characters
- Habit: The Solanaceae family includes herbs, shrubs, and some small trees.
- Root: They usually have a branched tap root system.
- Stem: Aerial, branched, erect, mostly herbaceous, cylindrical, hairy or smooth. Potato is an example of an underground stem.
- Leaf: Leaves are simple, alternate, and sometimes pinnately compound. Venation is reticulate. Leaves are exstipulate or sessile. Sometimes transformed into spines.
2. Floral Characters
- Inflorescence: Flowers are solitary or grouped having axillary or cymose inflorescence.
- Flower: Bracteate or ebracteolate, actinomorphic, and generally hermaphrodite. The flower is pentamerous and hypogynous.
- Calyx: Sepals green or coloured, typically 5 sepals, gamosepalous, persistent and show valvate aestivation.
- Corolla: Petals 5, gamopetalous and valvate or imbricate aestivation.
- Androecium: Stamens 5, polyandrous and epipetalous.
- Gynoecium: Bicarpellary, syncarpous with the superior and bilocular ovary. Each locule contains many ovules (1-50). The placenta is swollen and axile placentation. The ovary is placed obliquely. It contains one style and one simple or bilobate stigma.
- Fruit: It can be berry, e.g. tomatoes or capsules as in datura.
- Seeds: Contains many seeds that are endospermic. Seeds are mostly round and flat. The embryo is curved or straight with two cotyledons. Most plants contain 2n = 24 (2 x 12) chromosomes but polyploidy is also seen with chromosomes in multiples of 12.
- Pollination: Members of this family mainly exhibit entomophilous pollination, i.e. pollination by insects.