Hibiscus-Rosa-sinensis (China rose)

Malvaceae

The members of the family are worldwide in distribution especially in tropical regions of the world. The family consists 0f 82 genera and 1500 species. Commonly found species of Pakistan are: Hibiscus rosa-sinensis (china rose), Malva sylvestris, Alcea rosea (hollyhock), Abutilon (kangi), Gossypium (cotton), etc.

Distinguish Features:

Herbs of shrubs, simple alternate leaves, flower hermaphrodite, actinomorphic, pentamerous having epicalyx, sepal 5, petal 5, stamen numerous, monoadalphous, carpel numerous, fruit a carcerulus.

The representative species are:

Hibiscus rosa-sinensis (china rose).

Alcea rosea (hollyhock – gul-e-khaira).

Hibiscus-Rosa-sinensis (China rose – Gurhal, Shoe Flower):

Habit:

An ornamental shrub that flowers in most part of the year. The flowers yield a dye used in manufacture of shoe polishes.

Stem:

Erect, branched, cylindrical, herbaceous above and woody below, mucilaginous.

Leaf:

Cauline and ramal, simple, alternate, stipulate (stipules free lateral), petiolate, ovate, leaf margins serrate, reticulate multicostate.

Inflorescence:

Cymose – Solitary axillary.

Flower:

Ebracteate, pedicellate, complete, actinomorphic, bisexual, pentamerous, hypogynous.

Epicalyx:

5 – 7 bracteoles

Calyx:

5 sepals, gamosepalous, green, inferior.

Corolla:

5 petals, polypetalous, petals slightly united below and adnate to staminal tube, red or pink, inferior.

Androecium:

Stamens indefinite, monoadelphous, filaments of the stamens united to form a staminal tube around the style while anthers are free, anthers basifixed, inferior.

Gynoecium:

Pentacarpellary, syncarpous, ovary superior, pentalocular, placentation: axile, style long ending in five rounded stigmas.

Floral Formula: K5 C5 A∞ G(5)

Economic Importance:

The family is of great economic importance and included many very valuable economic plants.

Sources of Cotton wool:

Many species of Gossypium are grown for the hairy covering of the seeds which constitutes the “cotton wool” or “cotton” of the commerce. This is used for the manufacture of cloth, cellulose and other products. Failure of the crop means a tragedy for the poor farmers. Cotton treated with a strong alkali is made stronger and more or less silky and is known as ‘mercerized’ cotton, after Mercer, the discoverer of the method. Besides cotton, the plan furnishes many other products such as cotton seeds, oil, meal etc. Gun Cotton, a powerful explosive, is made by treating the cotton lint with nitric and sulphuric acids and by various subsequent transformations. Stem bark of some plants e.g., hibiscus cannabinus, Hibiscus subdarifa, Abutilon, Urena, Malachra, etc. Which yield fibers for the purpose of making ropes, mating etc. Albutilon avicennae is cultivated in China, on large scale for “China Jub” obtained at the rate of a ton per acre.

Ornamental Plant:

Many garden annuals like Althaea, Malva, Pavonia and shrubs like Hibiscus spp. And trees like Thespasia are the common ornamental species, highly prized on account of their large, showy flowers. The common hollyhock or Alcea rosea is a familiar garden plant with its large flowers of many colors and its double-flowered varieties.

Sources of Vegetables: Some vegetables yield vegetables e.g., Hibiscus esculentus (lady’s finger) furnish green capsules known as “okra or gumbo” vern. Bhindi, used in vegetables and soups.

Source of Drugs:

Malva sylvestris, yields a drug called Khatmi for horse throat. The roots of Urena rependa are used in hydrophobia.

Source of Wood:

Bombax malabaricum (Simbal), yields wood which is used in the match industry and silk-cotton for stuffing pillows.

Source of Oil:

Cotton seeds are used to extract oil which is hydrogenated to produce “Vanaspati ghee”, while the oil cake is used as fodder and manure.

Source of Color:

Petals of Hibiscus rosa-sinensis are used for cough and polishing shoes and coloring other articles. Sinhalese dye yellow with the capsule of Thespasia populnea. The coloring matter in the flower of Alcea rosea var. nigra is used in coloring wines in certain parts of Europe.

Some Important Genera of Family and Flowers:

Hibiscus rosa-sinensis (China rose)

Malva sylvestris

Alcea rosea (Hollyhock)

Abutilon (Kangi)

Gossypium (Cotton)

Malva parviflora

Malvestrum tricupidatum

Bombax malabaricum (Simbal)

The important genera of family Malvaceae and Flowers are as follow: