NCERT 9TH CLASS SCIENCE CHAPTER IMPROVEMENT IN FOOD RESOURCES
Food is the combination of various organic and inorganic substances which is capable of providing
(i) Energy for the various metabolic activities.
(ii) Materials for repair / replacement of worn-out tissues in the body.
(iii) Materials for growth & reproduction.
(iv) Regulatory substances, body secretions and metabolic activities etc. 70% of India’s economy is based on agriculture and 40% of G.N.P (Gross National Product) comes from agriculture.
(a) Agriculture : (Ager means field ; culture means cultivation). It is the applied biological science which deals with
the production of plants and raising of animals useful to man, involving soil cultivation, breeding and management of crops and livestock.
(b) Horticulture : (Hortus-garden ; cultura-cultivation). It is the branch of agriculture and the science of growing vegetables, fruits and ornamental plants.
(c) Silviculture: (Sylvan- wood and trees) Cultivation of wood and trees e.g.-pine, teakwood, sesamum etc.
(d) Sources of food : Plants provide us with foods like cereals, pulses, oil seeds, fruits and vegetables, on this basis plants are classified as follows :
(e) Crop Seasons : Different types of crops require different climatic conditions like :
(ii) Photoperiod (duration of light
(iii) Completion of life cycle
(f) Depending upon the growing season, there are two groups of crops :
Kharif crop/ Rainy season crop Rabi crop/ Winter season crop
(a) Grown during monsoon/rainy season (a) Grown during winter season
(b) They require warm and wet weather (b) They require cold and dry weather
(c) They are sown in June-July and (c) They are sown in October/November & harvested in harvested September/Octobe harvested in March-April
(d) Examples- Rice, Jowar, Bajra, Cotton,(d) Examples- Wheat, Barley, Gram, Peas, Groundnut,Urad, Moong etc. Mustard, Potato etc.
IMPROVEMENT IN CROP YIELD
To obtain the high yields from our forms the following three scientific approaches are adopted.
(a) Varietal improvement of crop through genetic manipulation.
(b) Crop Produc