improvement on food resources class ix
Answers
★Hey Mate★
★ It's BrainlyP7 ★
★ Brainly Ace ★
Your Answer : Plant and animal breeding and selection for quality improvement and management, Use of fertilizers, Manures, Protection from pests and diseases, Organic farming.
Facts that Matter
• Food supplies proteins, carbohydrates, fats, vitamins and minerals, all of which we require for body development, growth and health.
• Different crops require different climatic conditions, temperature and photoperiods for their growth and completion of their life cycle. Photoperiods are related to the duration of sunlight. Growth of plants and flowers are dependent on sunlight.
• Successful crop production depends upon many factors such as: (i) Understanding how crops grow and develop. (ii) Effect of various nutrients, climate, water on the growth of the plant. (iii) Modification and management of each factor for increasing the yield of the crop.
• The crops which are grown in rainy season (the kharif season, from June to October) are called as kharif crops. Example: Paddy, soyabean, pigeon pea, maize, cotton, green gram and black gram are kharif crops.
• The crops which are grown in winter season (the rabi season, from November to April) are called rabi crops. Example: Wheat grain, peas, mustard and linseed are rabi crops.
• Crop variety improvement: It can be done either by hybridisation or by introducing a gene. (i) Crop improvement by hybridisation: Hybridisation refers to crossing between genetically dissimilar plants. This crossing may be intervarietal (between different varieties), interspecific (between two different species of the same genus) or intergeneric (between different genera). (ii) Crop improvement by introducing a gene: This provides the desired characteristics and results in genetically modified crops.
• Cultivation practices and crop yield are related to weather, soil quality and availability of water. Since weather conditions such as drought and flood situations are unpredictable, varieties that can be grown in diverse climatic conditions are useful.
• The factors for which variety improvement is done are: (i) Higher yield: To increase productivity of the crop per acre. (ii) Improved quality: The quality of crop products vary from crop to crop. E.g., protein quality is important in pulses, oil quality in oilseeds, preserving quality in fruits and vegetables. (iii) Biotic and abiotic resistance: Biotic factors are the diseases, insects and nematodes while abiotic factors are the drought, salinity, water logging, heat, cold and frost which affect the crop productivity. Varieties resistant to these factors (stresses) can be improved to increase crop production. (iv) Change in maturity duration: Shorter maturity period of crop reduces the cost of crop production and makes the variety economical. Uniform maturity makes the harvesting process easy and reduces losses during harvesting. (v) Wider adaptability: It allows the crops to be grown under different climatic conditions in different areas. (vi) Desirable agronomic characteristics: It increases productivity, for example, tallness and profuse branching are desirable characters for fodder crops; while dwarfness is desired in cereals, so that less nutrients are consumed by these crops.
• Plant nutrients: Nutrients are supplied to plants by air, water and soil. There are sixteen nutrients which are essential for plants. Air supplies carbon and oxygen; hydrogen comes from water and soil supplies the other thirteen nutrients to plants. Amongst these thirteen nutrients, six are required in large quantities and are therefore called macro-nutrients. The other seven nutrients are used by plants in small quantities and are therefore called micro-nutrients.
• Manure: Manure contains large quantities of organic matter and also supplies small quantities of nutrients to the soil. Manure is prepared by the decomposition of animal excreta and plant waste. Manure helps in enriching soil with nutrients and organic matter and increasing soil fertility. On the basis of the kind of biological waste used to make manure, it can be classified into three types: (i) Compost (ii) Vermi-compost (iii) Green manure. (i) Compost: It can be farm waste material such as livestock excreta (cow dung etc.), vegetables waste, animal refuse, domestic waste, sewage waste, straw, eradicated weeds, etc. This material is decomposed in pits and this process of decomposition is also called composting. This compost is rich in organic matter and nutrients. (ii) Vermi-compost: The compost which is made by the decomposition of plant and animal refuse with the help of redworm is called vermi-compost. (iii) Green manure: Prior to the sowing of the crop seeds, some plants like sun hemp or guar are grown and then mulched by ploughing them into the soil. These green plants thus turn into green manure which helps in enriching the soil in nitrogen and phosphorus.
★ BrainlyP7 ★
★ Brainly Ace ★