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9th Std Science Syllabus

1.1. IMPROVEMENT IN CROP YIELDS
Food Nutrient Cereals Carbohydrates Pulses Protein Meat, (mutton, chicken....), fish and egg. Fat and protein Fruits and vegetables, especially green vegetables like spinach and cabbage Minerals and Vitamins
Food, in general, is derived from plants and animals. Food is required for growth, development and repair of the body. It also protects the body from diseases and provides energy. Food provides Proteins, Carbohydrates, Fats, Vitamins and Minerals.

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1.2 NUTRIENT MANAGEMENT
The higher yields of crops mainly depend upon input applications like improved seeds, fertilizers and modern techniques of sowing and harvesting. Plants require a number of nutrients for their growth and development.

1.3 USES OF MANURE AND FERTILIZERS
We can eliminate deficiency of nutrients by using manures and fertilizers.
Based on the kind of biological materials used, manure can be classified as,
i) Compost & Vermi Compost
ii) Green Manure

1.4 PROTECTION FROM PESTS AND DISEASES
Pests are organisms of plant or animal origin which damage cultivated crops or plant products in storage. Crop yield is lost due to pests during sowing, harvest, storage and consumption. This is a great loss to the national economy.

1.5 HYBRIDIZATION IN PLANTS AND ANIMALS
1.5.1 HYBRIDIZATION IN PLANTS
Hybridization is the method of producing improved varieties by crossing two or more plants of dissimilar genotypes together. A plant variety containing as many desirable characters as possible can be produced by hybridization.

8th Std Science Syllabus
1.1. AGRICULTURAL PRACTICES
With the increase in population , the demand for food has also gone up.
The available land for agriculture has been decresing. Therefore improved,
agricultural practices have to be introduced.

1.2. Basic practices of crop production
Production of crops involves several activities carried out by the farmers
over a period of time. These activities are given below.
** Preparation of soil and sowing
** Adding manure and fertilizer
** Types of irrigation
** Protection from weeds
** Harvesting
** Storage and Marketing

1.3. PREPARATION OF SOIL and Sowing
Before sowing the seeds, we have to prepare the soil. Preparation of soil is the first essential stage for cultivation of crops, in order to turn the soil and loosen it. It involves,
** Ploughing or tilling
** Levelling and
** Manuring

1.4. Irrigation
Plants need water for germination, drawing nutrients and preparing their
food by photosynthesis. The process of supplying water to crops in the field at different intervals is called irrigation. It varies from crop to crop, season to season and soil to soil. Some of the sources of irrigation are well, tube wells, ponds, lakes, rivers, dams and canals.

1.5. Protection from weeds (Unwanted plants)
Weeds are undesirable plants growing naturally along with the crop.
Removal of these weeds is called weeding. Weeding should be done
then and there. The weeds must be removed because,They compete with crops for water, nutrients, space and light therefore affect their growth.

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