CBSE Class 10 Science Economic Importance Of Plants Notes

 ECONOMIC IMPORTANCE OF PLANTS

INTRODUCTION:

1. Study of economically useful plants and plant products is known as Economic Botany.
2. Plants are of special importance in medicine to cure human beings. Study of plant medicines on body parts is known as Pharmacology.
3. Useful plants part can b e classified in various ways for example on the basis of useful plant parts or on the plant products.

Classification given by A. F. Hill 1952 is considered to be the most useful, Hill classified economically important plants in groups such as –

(i) Food plants - Cereals, pulses, vegetables and fruits.

(ii) Additional food plants - spices, beverages.

(iii) Medicinal plants – medicinal plants, chewing plants, narcotics

(iv) Plants of Industrial use - Plants used in production of fibers, timer, rubber, gum, and essential oils, fatty oils, sugar and starch.

(a) Cereals :

1. This is the most important group of food plants. Cereals are either a seed or a fruit of monocotyledonous cultivated grasses and known as caryopsis.
2. Some of the important cereals and their biological names are as follows.

(i)  Wheat – Triticum aestivum

(ii) Paddy or rice – Oryza sative

(iii) Millets – Pennisetum americanum

1. Maize – Zea mays
2. Wheat :
3. In Rajasthan wheat is swon in October to November as a Rabi crop, and harvested in March – April,

(i) Rice :

1. Half on the population of world use rice as their staple food.
2. In india it is swon in rainy season as kharif crop and harvested in the beginning of winter. This crop consumes highest quantity of water. In India rice grown in the states of Andhra Pradesh, Assam, Bihar, Karnataka, Tamilnadu, Maharashtra, Uttar Pradesh, Orissa and West Bengal.
3. In Rajasthan it is sown in districts of Bundi, Kota, Banswara, etc.
4. The improved varieties of rice are Basmati, Swarndana, Permal, and Jagannath

(ii) Pearl millet (Bajra) :

1. Peal millet is an important millet careal.
2. It is sown in dry and semi dry in unirirgated areas as a kharif crop.
3. In this it is sown in Rajasshthan, Hariyana, Maharashtra, and Uttar Pradesh at large scale.

(iii) Maize : In Uttarpradesh, Bihar, Madhyapradesh, Punjab, Maharastra and rajasthan as a Kharif crop.

1. Many commercial verieties of Maize such as Popconrn. Sweet maize, and Softcorn arre also in use.
2. Improved hybrid varieties of maize are Ganga white – 2, Vijay, Shakti, Rattan etc. Maize is used as Roti, Porridge, Bhutta, Corn flex etc.
3. Maize has many industrial uses so as to produce alcohol, cornstarch, corn oil etc.

(b) Pulses :

1. Pulses are also an important part of our food. It’s cotyledons are riceh in protein and amino acids.
2. Some iomporatant pulses and atheir botanical names are as follows.

(i)   Gram – Cicer arietinum   (ii) Mung – Vigna rediata

(iii) Urd – Vigna mungo  (iv) Cajanus – Cajanus cajan

All pulses are good sources of protein. Soyabean contains highest percentage of protein up to 35-40%.

1. Gram is known as King of pulses.
2. Out of many varieties of gram Kabuli, Indori and Desi kala chana are important.

(bc Vegetables : 

1. According to Brouck (1975) vegetables are a rich source of vitamins, mineral salts, water and indigestible roughage or fibers.
2. Common as well as botanical names of some important vegetable of Rajasthan are listed below.

(i) Vegetable s obtained from roots

1. Carrot (Gazar) – Daucus carota
2. Beat root, sweet potato and raddish are some other examples.

(ii) Vegetable obatained from stem

1. Potato (Aloo) – Solanum tuberosu. Obtained from under ground tuber.

(iii) Vegetables obtained from leaves

1. Cabbage (Band Gobhi) – Brassica oleracea var. capitata
2. Spinach (Palak) – spinacia Oleracea.
3. Fenugreek (Methi), Amaranths (Chaulai), Portulaka and Salad are some other examples.

(iv) Vegetables obtained from inflorescences

1. Cauliflower (Phool gobhi) – Brassic oleracea var. botrytis

(v) Vegetables obtained from fruits

1. Lady’s finger (Bhindi) – Abelmoschus esculentus (ii) Brinjal (Baingan) – Solanum melongena.
2. Tomatoes (Tamater) – Lycopersicon esculentum
3. Other examples are bitter gourd, Lufa Gourd, Musk melons, water melon, Pumkins, Pea, Cowpea, Soyabean, Guar, Jackfruit, Parwal (Trichosanthes) etc.

(d) Spices :

(i) Spices obtained from stem :

1. Turmeric (Curcuma longa) : It’s yellow orange colour is due to curcumin. Curcumin is supposed to be the blood purifier and beautifier.
2. Garlic (Allium sativum) : It’s pungent small is due to a substance Alicin. Garlic is used as a apice as well as medicine.
3. Other examples are ginger (Gingiber ofcinal), Asafotida, Cinnamon etc.

(ii) Spices obtained form leaves :

1. Some important spices obtained from leaves are Cassia (tej patta), meethaneem, suva, mint, etc.

(iii) spices obtained from fruits :

1. Chilly – Capsicum annum B. Coriander – Coriadrum sativum
2. Foeniculum – Foenculum vulgare D. Cumin – Cuminum cyminum
3. Parsley – Trachespermum ammi
4. Others spices obtained from fruits are Peepal, Foenumgreekum, Black Cumin, Mace, Nutmeg, Black Pepper, Colve (from flower bud).

(e) Fruits :

Fruits contain minerals, vitamins, micro – nutrients besides sugar and water. Name of some important fruits are as follows –

1. Mango – Mangnifera Indica B. Banana – Musa paradisiacal
2. Guava – Psidium guajava D. Orange – Citrus reticulate

(f) Other food plants:

Edible fatty oils : Main edible oil producing plant are – Mustard, Sesamum, Groundnut, Soyabean, Sun flower, Kusum, Coconut, Ram til etc. Palm oil is obtained from a palm tree.

Sugars : For industrial production sugar only sugar cane and bat roots are considered valuable.

Beverages : Tea is produced form leaves of shrub known as Camellia sinensis and coffee from powdered roasted seeds of Coffee Arabica.

PLANTS OF MEDICINAL IMPORTANCE :

List of medical plants of Rajasthan and the medicine obtained from them are as follows –

(i) Medicine from fruit :

1. Ashvagandha – Withania somnifera
2. Safed mushli – Chlorophytum tubereosum
3. Some other examples are – Serpentine, Liquorice (Mulhati), Asparagus, Anantmool, Pannerva etc. 

(ii) Medicine from bark :

1. Arjun – Terminalla arjuna
2. Bark of Cinchona is very useful for the treatment of malaria, but Cinchona trees do not grow in Rajasthan.

(iii) Medicine from stem :

1. Guggle is resin, obtained form stem and bark of commiphora wightil.

(iv) Medicine from leaves :

1. Adusa – Adhatoda vasica             B. Ocimum – Ocimum Sactum
2. Brhami – Centella asiatica             D. Aloe – Aloe vera
3. Others are Bhringja, Neem, Be3ladonea, Euclyptus, Sena, Chirayta.

(V) Medicine from flower, fruit or seed.

1. Opium – Papaver somniferum
2. Amvala – Emblica officinalis
3. Other examples are Datura, Charas, Gokharu etc.

Ashvagandha :

1. Dry roots or withania somnifera are known as Ashvagandha.
2. Colour of Ashvagandha root is yellow or creamish, roots contain an alkaloid known as Somniferine.

It has energetic and repressive properties.

Opium :

1. Opium is obtained as latex form unriped fruits of Papaver somniferum. It’s oily seeds are known as Khas Khas.
2. Incisions are made on the surface of unripe fruits. It produces latex called opium on drying.
3. latex contains more than thirty alkaloids, but morphine and codeine are important.

Opium has repressive, analgesic and hypnotic effects.

1. Rajasthan and Madhya Pradesh are producers f opium in India. In Rajasthan it is cultivated in districts of Chittodgarh, Bhilwara, Udaipur and Jhalawar.
2. Guggul or Indian ledellium :
3. Guggul is an oleoresin obtained from bark of the plant. It is used in many of the Ayurvedic medicine.
4. Guggul plant is a slow growing but perennial herb of plateau regions. It is an endangered species yet growing in rajasthan normally.
5. Guggul containing medicines are used to control cholesterol, treat piles, and as a cough expectorant, a repressive etc. 

PLANTS OF CONSTRUCTIONAL IMPORTANCE : 

(i) Fibres:

Hill (1952) classified plant fibres in six groups on the basis of their utility. These are fibers obtained mainly form stems, leaves and seeds of plants.

Six plant fibre groups are:

1. Textile fibres: Cloth, ropes, packing bags and strings are made from these from these fibres.
2. Brush fibres: Broom and brushers are made from these fibres.
3. Rough weaving fibres: Baskets and mats are mats are made from these fibres.
4. Filling Fibres: These are used to fill mattresses, pillows, quilts etc.
5. Natural fibres: These are used directly without weaving, to cover body.
6. Paper making fibre: These are used to make paper and card boards.

Main fibre producing plants are enlisted here

Out of 30 species of cotton. G, barbedense and G. herbecium are sown mostly. Cotton fibres are out growth of seed coat.

Cotton is first converted into fibre, then cloth, trigs, mats bed sheets are made from it. Fibreless seeds of cotton is known as Binolla, oil and oil –cake are made from it.

Jute : Corchorus capsularis : fibres of phloem. Other fibre producing plant are – Coconut. Chorchus, Sun, Munja, Alsi, Hemp, Samal Aloe etc.

Fibre obtained from coconut fiuit are coir.

(iiTimber:

Secondary xylem of perennial dicotyledonous and gymnosperm plants is known as wood. Heavy weight of plant body is supported by wood.

Wood of gymnosperm like Pine, Cedurs etc. is known as soft wood where as that of dicotyledonous like Teak, Sal, Acacia, Shishem etc. is called as hard wood.

The wood from which widows and doors are made is known as timber wood.

Some plants for timer wood production of Rajasthan and other states are enlisted  as below :

1. Teak – Tectona grandis B. Shishem – Dalbergia sissoo
2. Rohida or Markwar Teak – Tecommells undulate D. Khejri or Prosopis – Prosopis cineraria

Marwar Teak or Rohida or Wave leaved Bignoina :

Wood of Rohida is hard, smooth and stripped. Furniture, doors and toys are made from it

Teak : Inner wood of teak is hard, brown and resistant to white ants, fungi and humidity.

Teak wood stands first in quality woods of the world. It is the best wood from carpenter and polish point of view.

This wood is used in making of all kinds of furniture. Doors of houses, windows, railway coaches. Slippers, cabinets etc.

Name of town Sagwara in Dungarpur districit is an indicator of abundence of teak (Sal) forests.

Salix albs is used to make circket bat.

Central Drug Research institute is located at Lucknow.

Central Rice Research institute is located at Cuttack.