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fibre crop of commercially important and an industrial crop. It is grown in India, U.S.A, former USSR countries, China, Brazil, Egypt, Pakistan, Mexico, Turkey and Sudan. In India, it is grown in Maharastra, Gujarat, Karnataka, Andhra Pradesh, Tamil Nadu, Punjab, Rajasthan, Haryana and Uttar Pradesh. Cotton is a heat l...
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day plant, flowering can be photoperiodically controlled. It requires an optimum temperature of 26–32°C for growth. 14. Potato Being a crop of temperate crop, requires a cool temperature. Ideal temperature for vegetative growth is 24°C and that for tuberisation is 18-20°C. It is susceptible to frost and requires bright...
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at least 3 months bajra, small millets (iv) Rainfall 5-10 cm/month grasses (v) < 5 cm Not suited for crop production (c) Length of crop season Effective crop growing period cropping system < 20 weeks Sole crop 20-30 weeks Sole crop + Inter crop > 30 weeks Two crops in sequence (ii) Natural resources (a) Soil Cropping p...
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processing industries. Farmers prefer a crop, the produce of which will fetch high price in the market. In earlier days sunflower and soybean were grown in limited areas due to lack of processing industry. Now, due to industrial development they are grown in large scale. (v) Economics The ultimate objective of commerci...
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It refers to planting of the succeeding crop before harvesting the preceding crop. e.g., (i) Rice–Black gram (rice fallow pulse), (ii) Rice–Lathyrus, (iii) Rice–Lucerne, (iv) Rice–Berseem and (v) Cotton–Berseem. Here the seeds of black gram, lathyrus, lucerne or berseem are broadcasted in standing rice or cotton crop j...
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should require similar agronomic practices. • Erect growing crops should be intercropped with cover crop. • Erosion permitting crop should be intercropped with erosion resisting crop. • The component crops should have different rooting pattern and depth of rooting. B. Types of intercropping based on Interactions 1. Par...
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machine and power throughout the year. • It is an insurance against drought. D. Difference between intercropping and mixed cropping Intercropping Mixed cropping 1. The main objective of intercropping The main objectives of mixed cropping are insurance against is to utilize the space between rows crop failure. Purpose i...
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same time. It is practiced in orchards and plantation crops for maximum use of solar energy even under normal planting density. e.g., Sugarcane, potato and onion, coconut, pepper, cocoa and pineapple. 3.4 CROP ROTATION Crop rotation may also be defined as a process of growing different crops in succession on a piece of...
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demand based. • The crop of the same family should not be grown in succession because they act as alternate hosts for insect pests and diseases. • An ideal crop rotation is one, which provides maximum employment to the farm family and labour and permits efficient use of machines and equipments and ensures timely agricu...
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physical properties of soil. • Controls certain soil borne pests and disease. • Reduces the pressure of work due to different farm operations in a stipulated period of time. 3.5 CROPPING PATTERNS AND CROPPING SYSTEMS Cropping pattern is the yearly sequence and spatial arrangement of crops or crops and fallow on a given...
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of economically preferable crops or cropping system in a region. To describe the cropping pattern of a region the crop occupying the highest percentage of the sown area in a particular season or year of the region is taken as the base crop. • a substitute for base crop in the same season. CROPS AND CROP PRODUCTION 183 ...
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turmeric, betel vine etc. 2. Millets based cropping patterns– (a) Maize based cropping patterns Maize is grown in sequence with sugarcane, groundnut, cowpea, cotton etc. In India twelve cropping patterns were identified with maize. (b) Sorghum based cropping pattern Seventeen patterns were in practice in India. (c) Pea...
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– Cotton (July-October) – (October-February) (February-July) Rice – Rice – Black gram/Green gram/Gingelly Rice – Rice – Groundnut (b) Irrigated dry cropping patterns Cotton – Sorghum – Ragi (August-February) (February-March) (June-August) Sorghum – Fodder sorghum – Cotton (August-November) (November-January) – (Februar...
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Early maturity (in some cases late maturity). • Resistance to lodging. • Drought, flood and salinity tolerance. • Tolerance to insects and diseases. • Chemical composition of grains (high percentage of oil, increase in protein quantity or quality, etc.). • Quality of grains (fineness, coarseness, etc.). • Quality of st...
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total amount and seasonal distribution greatly affects the choice of cultivated crops of a place. Low and ill-distributed rainfall are common features of dry farming wherein drought resistant crops like sorghum, pearl millet, Italian millet and other minor millets are commonly grown. On the other hand in places of heav...
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temperature of a place is largely determined by its distance from the equator (latitude) and the altitude. Based on the above, the vegetations are classified as tropical, temperate, taiga, tundra and polar. Some investigators have classified the vegetative of the world into four classes on the basis of prevailing tempe...
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Maize 8–10 20 40–43 Sorghum 12–13 25 40 Rice 10–12 32 36–38 Tobacco 12–14 29 35 B. Daily cycle of temperature (Diurnal Variation) From sun rice until 2-4 pm, when the energy is being supplied by incoming solar radiation is faster than it is being lost by earth by re-radiation, the air temperature rises. From about 2-4 ...
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location. The average decrease is approximately 0.65oC/100 m. (6.5o C/km). This is knows as normal lapse rate or vertical temperature gradient. 188 A TEXTBOOK OF AGRONOMY D. Temperature inversion Although normally, the lower several miles of atmosphere show a decrease in temperature with increasing altitude, this condi...
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affects the plant life. The growth of higher plants is restricted to a temperature between 0–60oC and the optimum 10oC–40oC. Beyond these limits, plants are damaged severely and even get killed. The maximum production of dry matter occurs when the temperature ranges from 20 to 30oC. Apart from yield reductions, many vi...
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of oxygen. Ice in contact with roots inhibits diffusion of carbon dioxide and the respiratory products may become harmful to plants. CROPS AND CROP PRODUCTION 189 Heaving Injury to plants is caused by a lifting upward of the plant along with the soil from its normal position in temperate regions where snowfall is commo...
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fruits and in extreme cases death of plants. (i) Sun clad: Injury caused by high temperature on the sides of bark is known as sun clad. This is nothing but exposure of barks of the stems to high temperature during daytime and low temperature during nighttime. (ii) Stem girdle: It is another injury associated with high ...
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light is limiting, temperature has little effect on the rate of photosynthesis. When light is not limiting, it has a profound effect on the rate of photosynthesis. In general, high temperature accelerates growth process. Rarely are high temperatures per se the direct cause of death of plants, provided the water supply ...
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the atmosphere varies. Variations in air temperature are much greater over the land than over the water. The differential heating process between land and sea surfaces are due to their properties. It is one of the reasons for Indian monsoon. Ocean currents The energy received over the ocean surface carried away by the ...
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III. Atmospheric humidity Water is always present in the atmosphere in the form of invisible water vapour, normally known as humidity of the air. When the atmosphere contains the maximum possible amount of water vapour it is said to be saturated at the particular temperature and pressure. Any increase in temperature, w...
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is contained. Relative humidity: Relative humidity is a common parameter for expressing water vapour content CROPS AND CROP PRODUCTION 191 of the air. It is the percentage of water vapour present in the air in comparison with saturated condition at a given temperature and pressure. The R.H. can be expressed as 100r RH ...
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of insect parasites such as aphids and jassids thrive well moist conditions. RH on Plant growth Increase in RH decreases the temperature. This phenomenon increases heat load of the leaves. Since transpiration is reduced not much heat energy used. Excessive heat due to closure of stomata entry of CO2 is reduced. Reducti...
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which causes extensive damage to crop plants. e.g., (a) Blight disease on potato. (b) The damage caused by thirips and jassids on several crops. • High humidity at grain filling reduces the crop yields. 192 A TEXTBOOK OF AGRONOMY • A very high relative humidity is beneficial to maize, sorghum, sugarcane etc, while it i...
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earth such as coal, oil and wood etc., are nothing but converted form of solar energy. The word ‘insolation’ is contraction of “incoming solar radiation”. Radiant energy from the sun that strikes the earth is called insolation. Fig. 3.1 Solar energy provides two essential needs of plants (a) light, required for photosy...
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March Spring Winter Sun’s rays Equator 146.2 m km Perihelion 3rd January Winter slostice 21 December Autumn Sun Aphelion 4th July Summer soistice 21 June 154 m km Autumn equinox 23 September Summer Sun’s rays Arctic circle CROPS AND CROP PRODUCTION 193 Solar constant is defined as the rate at which solar radiation is r...
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with change in temperature and relative humidity and therefore it is difficult to evaluate light effects alone. Generally speaking light intensity falling at a particular place is normally enough for the plants and their physiological phenomena viz., photosynthesis. In photosynthesis about one percent of the light ener...
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under high light intensity if water is available in plenty. However crops like betelvine, turmeric, buckwheat, and tobacco grown during summer produce greater dry matter if slightly shaded. 2. Quality of light When white light is passed through a prism it is dispersed into wavelengths of different colors; violet 400-43...
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Plants which develop and produce normally when the photoperiod is greater than a critical minimum (more than 12 hours of illumination) are called ‘long day plants’ (sugar beet, wheat, barley) and those develop normally when the photoperiod is less than a critical maximum (less than 12 hours of illumination) are called ...
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mainly due to ultra violet and violet rays of the sun. Instruments used for measuring solar radiation Bellanis pyranometer, Sunshine recorder, Line quantum sensor, Photometer, Lux meter measures the light intensity and Radiometer. V. Wind velocity and its effect on crop production Air in horizontal motion is known as w...
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is the value obtained by averaging the wind speed (irrespective of direction) for a whole day. This averaged for all the days of a month is the mean daily wind speed for that month. The daily values averaged for all the 365 days of the year is the annual mean daily wind speed. 2. Wind Direction: Winds are always named ...
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by the end of September. These changes bring on heavy and continue rainfall to the Southern and South Eastern India. (a) Mechanical effects • Wind causes mechanical lacerations and bruises on the tissues of crop plants, • Violent winds causes lodging of crop plants such as wheat, maize, sugarcane, rice etc., • A very h...
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AGRONOMY (d) Remedy Velocity of wind can be reduced by growing tall, sturdy trees across the direction of the wind as wind breaks. To arrest the movement of soil by wind erosion shelterbelts of vegetation are raised. VI. Atmospheric gases The atmosphere surrounding the earth contains a mixture of gases viz., carbon dio...
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decomposition of dead plants and animals also adds N to the soil. The N in the soil is made available to the crops by the activity of nitrifying bacteria. Certain gases like SO2, CO and HF when released into the air in sufficient quantities are toxic to plants. A. Edaphic factors Plants grown in a land are completely d...
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that represents total stress with which water is held by the soil. Soil air Aeration of the soil is absolutely essential for the absorption of water by roots. O2 is required for respiration of roots and microorganisms. In poorly aerated soil the CO2 get accumulated and is detrimental, for absorption of water by the roo...
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Zn, Cu, Co, Iodine and Fe are also present in very small quantities. Soil organic matter The soil organic matter content varies from less than 1% in arid sandy soils to as much as 90% of dry weight of well developed soil. It has a marked influence on the soil properties and growth of crops. The organic matter of the so...
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Soil reaction Soils may be neutral, acidic or alkaline depending upon their content of basic salts and acidic components. Neutral soils are the best for growth of most crops. Soil acidity beyond a particular limit (soil with low pH) is injurious to the plant growth due to: • Aluminium toxicity under high acidity. • Int...
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soil nutrients and light. In dry farming condition weeds compete with crops for water. In irrigated tracts, the competition is severe for nutrients. Weeds in fallow land deplete the soil of both moisture and nutrients. (c) Plants as Parasites A plant parasite is dependent on its host plant for its existence. Parasitic ...
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soil, Ingestion of organic matter and mineral matter results in a constant mixing of these materials in the soil there by favours better growth of plants. (b) Small animals Small animals like rabbits, squirrels and field rats also cause excessive damage to field and garden crops. (c) Large animals Large animals like do...
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damage caused by heavy winds. 4. Direction of the mountain chains: It governs the distribution of the rainfall during monsoon and also the type of crops in dry farming. D. Anthropic (socio economic) factors • Man/women produce changes in plant environment and are responsible for scientific crop and soil management, • b...
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applied meteorology, which investigates the physical conditions of the environment of growing plants or animal organisms. It is an applied science, which deals with the relationship between weather/climatic conditions and agricultural production or it is a science concerned with the application of meteorology to the me...
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fertilizer and chemical sprays when rain is forecast • Judicious irrigation to crops. AGRICULTURAL METEOROLOGY 201 • Efficient harvesting of all crops. • Reducing or eliminating outbreak of pests and diseases. • Efficient management of soils, which are formed out of weather action. • Managing weather abnormalities like...
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to farmers. It enables to forecast the crop yield based on weather to plan and manage food production changes in a region. It is needed to make the farmers more “weather conscious” in planning their agricultural operations. The study of agrometeorology is needed for the following reasons: • To study climatic resources ...
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OF AGRONOMY 4.3 CLIMATOLOGY Climatology is compounded of two Greek words, “klima + logos”; klima means slope of the earth, and logos means a study. In brief, climatology may be defined as the scientific study of climate. In the early civilization, Gods were often assigned to the climatic elements, Indians still hold ce...
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for calculating the climatic averages of different weather elements. B. Factors affecting Weather and Climate Latitude Based on latitude, the climate has been classified as: (i) Tropical, (ii) Subtropical, (iii) Temperate and (iv) Polar. The tropical climate is characterized by high temperature throughout the year. Sub...
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heat energy, variations in temperature are created at different places. In black soil areas, the climate is hot; while in red soil areas, it is comparatively cooler due to lesser heat absorption. AGRICULTURAL METEOROLOGY 203 Nearness to large water bodies (Nearness to sea) The presence of large water bodies like lakes ...
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of the soil surface, relief forms–all these may create special local conditions of temperature, humidity, wind and radiation in the layer of air near the ground which differ sharply from general climatic conditions. It is concerned with the study of the properties of air near the ground and surface layer of soil, which...
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and the south pole. It divides the earth’s surface into the northern hemisphere and the southern hemisphere. Longitude: (Length) The distance of a place east or west on the meridian of Greenwich, England or the prime meridian as an angle is known as longitude. Meridian: A great circle of the earth passing through the g...
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a medium for transportation of pollen. • Protects crops and human beings from harmful UV rays. • Provides rain to field crops. A. Composition The atmosphere is a mechanical mixture of many gases, not a chemical compound. In addition, it AGRICULTURAL METEOROLOGY 205 contains water vapour volume (4% of atmospheric compos...
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Relatively inactive chemically. It regulates combustion by diluting O2 and indirectly helps oxidation. Mainly diluent. CO2 Plants take CO2 in the process of photosynthesis. It is an efficient absorber of heat from upper atmosphere as well as the earth. It emits half of the absorbed heat back to earth. It influences flo...
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in the humid tropics. The variations in this percentage over time and place are very important considerations climatically. Like CO2, water vapour has insulating action of the atmosphere. It absorbs not only the long wave terrestrial radiation, but also 206 A TEXTBOOK OF AGRONOMY a part of the incoming solar radiation....
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as well as cyclones and anticyclones occur in this sphere because of the concentration of almost all the water vapour (4% of the atmosphere composition) aerosols in it. Wind velocities increase with height and attain maximum at the top. Most important is decrease in temperature with increasing elevation up to 14 km. St...
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of atmosphere begins to occur. Above ozonosphere, the temperature falls again reaching a minimum of about 100oC at a height of 80 km above earth’s surface. Beyond this level, the temperature increases again due to the absorption of short wave solar radiation by the atoms of N in this ionosphere. Layers of ionosphere D ...
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shells, each of which has its own distinctive composite. 208 A TEXTBOOK OF AGRONOMY (a) Nitrogen layer 200 km above earth’s surface -molecular N. (b) Oxygen layer Average height 1120 km. atomic oxygen (c) Helium layer 3520 km (d) Hydrogen layer Arranged based on the weight of the gases. C. Lapse Rate The decrease in ai...
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PET. Climate Number of humid months % Geographical area of India Arid < 2.0 17.00 Semiarid-dry 2.0-4.5 57.17 Semiarid-wet 4.5-7.0 12.31 Humid > 7.0 1.10 The ICAR under All India Coordinated Research Project on Dry land Agriculture adopted classification based Moisture Deficit Index (MDI) AGRICULTURAL METEOROLOGY 209 P ...
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the general ground level. A. Classification of Clouds Clouds are usually classified according to their height and appearance. For convenience, we can list them in descending order viz., high clouds, middle clouds and low clouds. We must exercise some caution in relying on height data. There is some seasonal as well as ...
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clouds and sunshine without shadow. It does not produce precipitation. 2. Cirrocumulus (Cc) Like cirrus clouds, ice crystals are present in these clouds also. It looks like rippled sand or waves of the seashore. It contains white globular masses and transparent with no shading effect. The sky is mackerel sky. 3. Cirros...
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parallel rolls pushed together or broken masses. The air is smooth above these clouds but strong updrafts occur below. 2. Stratus (St) These clouds are also composed of water. It looks like for as these clouds resemble grayish white sheet covering the entire portion of the sky (cloud near the ground). It is mainly seen...
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other materials that are present in the atmosphere. These materials are called “Cloud Condensation Nucleus” (CCN). Without these, no cloud formation will take place. Certain special types known as “ice nucleus” on which cloud droplets freeze or ice crystals form directly for water vapour. Generally, condensation nuclei...
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The size and concentration of cloud droplets and ice particles. • RH should be 75%. • Wind velocity (20 km). • Cloud seeding. D. Principles of Rainmaking Clouds are classified into warm and cold clouds based on cloud top temperature. If the cloud temperature is positive, these clouds are called warm clouds and if it is...
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is heavy and falls rapidly from top of cloud and has no persistent effects due to cloud seeding. Aircrafts are commonly used for cloud seeding with dry ice. Aircraft flies across the top of a cloud and 0.5-1.0 cm dry ice pellets are released in a steady stream. While falling through the cloud, a sheet of ice crystals i...
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the top of the cloud, if area to be covered is large. (b) Seeding of warm clouds 1. Water drop technique Coalescence process is mainly responsible for growth of rain drops in warm cloud. The basic assumption is that the presence of comparatively large water droplets is necessary to initiate the coalescence process. So,...
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monsoon is the most important as it contribute 80–95% of the total rainfall of the country. (a) South West Monsoon (SWM) In the beginning of the year, temperature of the Indian Peninsular rapidly rises under the increasing heat of the sun. A minimum barometric pressure is established in the interior parts of the Penins...
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Winter rainfall It is restricted more to northern India and is received in the form of snow on the hills and as rains in the plains of Punjab, Rajasthan and central India. Western disturbance is a dominant factor for rainfall during these months in northwestern India. Table 4.2 Rainfall Distribution in Tamil Nadu in Di...
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also demands a definite amount of heat, it provides a link between water budget and heat budget. Factors affecting evaporation The evaporation from a fully exposed water surface is the function of several environmental factors. 1. Environmental factors Water temperature With an increase of temperature, the kinetic ener...
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plant parts, translocation of water in the plants and translocation of minerals in the plant. Factors affecting transpiration (i) Environmental factors Light: By directly opening and closing of the stomata, there is periodicity in the transpiration rate. Indirectly by increasing the temperature of leaf cells, the trans...
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maximum rate of evapotranspiration from an extended surface of 8–10 centimeters tall green grass cover, actually growing and completely shading the ground under limited supply of water. Potential evapotranspiration (PET) Potential evapotranspiration (PET) for any crop is obtained from reference evapotranspiration and c...
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Radiation from the sun evaporates the water as water vapour from the oceans into the atmosphere. The water vapour rises and collects to form clouds. Under certain conditions, the cloud moisture condenses and falls back to the earth as rain, snow, hail etc. Precipitation reaching the earth’s surface may be intercepted b...
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maritime, air masses are drawn only from a short distance. But by the end of May or the first week of June, when the low pressure centre has fully developed, the pressure-gradient is steeped so that even the trade winds from southern hemisphere are drawn towards the thermal low positioned in north-western region of the...
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high, the difference in the amount of rainfall between the windward and leeward side is rather negligible. Some of the air currents from the Arabian sea branch manage to proceed towards Chhota Nagpur plateau through the Narbada and Tapit gaps. These air currents ultimately unite with the Bay of Bengal branch. AGRICULTU...
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moisture. The southward decrease in rainfall is due to the increasing distance form the Himalayas, which cause the forced ascent of rain bearing air currents. (c) Winter Monsoon A secondary high pressure system develops over Kashmir and the Punjab. The high pressure area controls the prevailing wind direction over the ...
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table. The factors affecting runoff are the amount and intensity of precipitation, temperature, characters of the soil, vegetative cover of the area and slope of the land. It may be a direct return of rainfall or the flow from melted snow and ice fields-which have temporarily stored water. When rain occurs, the proport...
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in others they follow a seasonal pattern. Two types storms causing flood are: • Violent thunder showers, which is of short duration and produces a flash flood. • Prolonged wide spread rain which through sheer quantity of water, creates extensive flooding over entire watersheds. (b) Damages The damages due to flood are:...
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for immediate relief e.g., rice: 1.0% urea + 0.5% ZnSO4. • Spray fungicides to protect the crop from fungal diseases, which are common under high moisture condition. 4.12 WEATHER ABERRATIONS 1. Dry spells The interval between the end of a seven day wet spell, beginning with the onset of effective monsoon and another ra...
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three out of these seven days must be rainy with rainfall more than 2.5 mm on each day. In this, “x” is the amount of rainfall, which brings the top 50 cm soil layer to field capacity. The water holding capacity varies with the type of soil. For example, the value of “x” is equal to 83 mm for light soils, 125 mm for me...
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situation in which the amount of water required for transpiration and evaporation by crop plants in a defined area exceeds the amount of available moisture in the soil. • A situation of no precipitation in a rainy season for more than 15 days continuously. Such length of non-rainy days can also be called as dry spells....
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the onset of monsoon. If monsoon is delayed up to late October, crops like bajra, pulses, sunflower etc., can be raised. If it is very much delayed up to first week of November, crops like sunflower can be sown. (b) Breaks in the monsoon rains-Intermittent drought The breaks can be of different durations. Breaks of sho...
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of September and in 10% of the years, it withdraws during the month of December. Since, crops and varieties in any given region are selected based on the normal length of growing season. Persistence of rains much beyond normal dates creates an extraordinary situation. Under Kovilpatti (Tamil Nadu) conditions, short dur...
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a method of arranging various data of climatic parameters to demarcate a country or region into homogenous zones, i.e., places having similar conditions. A. Advantages The classification would enable in exploring agricultural potentiality of the area. Locating similar type of climate zone will enable in identifying the...
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influenced by external and internal factors that occur during the crop growing period. The external environment is the climate, which regulates and determines the growth and development and final output of crop plants. But, man has no control over weather alone, because its dominance over the success or failure of agri...
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in introduction of any crop. e.g., introduction of groundnut in peninsular India from Africa and long grained patnai rice into California. • Useful to forecast the abnormal weather. B. Climatic Normal for Crop Plants 1. Rice Besides rainfall, temperature and solar radiation influence rice yield by directly affecting th...
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the number and development of spikelets and thereby the yield. For getting grain yield of 5 t/ha, a solar radiation of 300 cal.cm2/day is required. A combination of low daily mean temperature and high solar radiation during reproductive phase is good for getting higher yield. Rainfall Rice requires high moisture and he...
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estimated to range between 41 and 64 cm. From germination up to the earing stage, maize requires less water. However, at flowering, it requires more water and the requirement reduces towards maturity. 4. Groundnut Temperature It is a tropical crop. It can be raised under a wide range of temperature. However, both very ...
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stage is undesirable. Dry autumn months are desirable for good quality produce. Excess rainfall at later stage may cause shedding of leaves, squares and bolls. It also stimulates top growth, delays maturity and changes colour of lint. High humidity favours many pests and diseases. 6. Sugarcane Mean temperature for opti...
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the required forecast, which decides the crop production in a region and ultimately the country’s economy. The planning for moisture conservation under weak monsoon condition and for flood relief under strong monsoon condition is important in a region. A reliable weather forecasting when disseminated appropriately will...
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farming such as strong winds, extended dry or wet spells. This type of forecast helps to determine sowing time and depth of sowing; in planning of irrigation; in making decisions on harvesting and time of spraying to get higher efficiency and in managing labourers and equipments. 3. Long range forecast It is valid up t...
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forecasting anticipated heavy rains, • Irrigation from wells can be avoided by which we can save electricity. • The harvesting could be advanced if the crop is in maturity stage. • Threshing of harvested produce could be done before rains by which crop losses can be avoided. Loss of seed, diesel, labourer and time can ...
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charts plotted for different synoptic hours (00, 03, 06, 09, 12, 15, 18, 21 UTC) depict the distribution of pressure, temperature, dew point, clouds, winds, present and past weather. In place of GMT, UTC (Universal Time Co-ordinate) is used. The upper air charts are also prepared at the standard pressure levels of the ...
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with shading Amount of clouds In addition to the above, different symbols are used for recording weather phenomena. Fig. 4.3 2. Weather calendar In order to provide the farmers with an efficient weather service, it is essential that the weather forecaster should be familiar with the crops that are grown in a particular...
Agricultural_studies.pdf
Agri life sciences
Growth stage MSL (m) 1 Rice <10°C 22-25 (flowering) 1500 <3000 20-21 (grain formation) 20-25 (ripening) 2 Maize 35-44°C 3 Sorghum 7-10 25-30 Short day 4 Pearl millet 28-32 400-750 5 Finger millet 500-1000 6 Kodo millet 400-500 7 Wheat 20-22 16-22 250-1800 <3500 8 Barley 12-15 (growth) Long day 400-500 30 (reproduction)...
Agricultural_studies.pdf
Agri life sciences
judicious and optimal management of both land and water resources. Hence, comprehensive and reliable information on land use/cover, forest area, soils, geological information, extent of wastelands, agricultural crops, water resources (surface and underground) and hazards/natural calamities like drought and floods is re...
Agricultural_studies.pdf
Agri life sciences
spectrum. The photographic technique is used to identify soil types, plants grown, disease incidence and drainage patterns. Line scan and related system: The system uses the visible and near infrared portion of the spectrum. In this system, a mirror is rotated parallel to the direction of the movement of the aircraft o...
Agricultural_studies.pdf
Agri life sciences
application of remote sensing techniques. The digital image processing, using powerful computers, is the key tool for analyzing and interpretation of remotely sensed data. The advantages of satellite remote sensing are: • Synoptic view – Wide area can be covered by a single image/photo (One scene of Indian Remote Sensi...
Agricultural_studies.pdf
Agri life sciences
the electromagnetic spectrum. INSAT-3A was launched on 10th April, 2003. D. Application Remote sensing techniques are used in agricultural and allied fields for the following reasons: • For collection of basic data for monitoring crop growth • For estimating the cropped area • For forecasting the crop production • For ...
Agricultural_studies.pdf
Agri life sciences
• Pest, disease and weed infestation • Wild life inventory • Fire surveillance. Application of livestock surveys • Population studies, distribution of animals • Animal behaviour, health of animals • Types of farm buildings. E. RS in India India, with the experience gained from its experimental remote sensing satellite ...
Agricultural_studies.pdf
Agri life sciences
F. Organizations using RS Techniques • National Remote Sensing Agency (NRSA), Hyderabad • Space Application Centre (SAC), Ahmedabad • National Bureau of Soil Survey and Land Use Planning (NBSSLUP), Nagpur • Central Ground Water Board ( CGWB) • National Institute of Oceanography (NIO) • All India Soil and Land Use Surve...
Agricultural_studies.pdf
Agri life sciences
of growth of a healthy crop depends on the rate at which radiation is intercepted by foliage and/or on the rate at which water and nutrients are captured by root systems and therefore, on the distribution of water and nutrients in the soil profile. The crop development is described in terms of various phenophases throu...
Agricultural_studies.pdf
Agri life sciences