Basics of Agronomy for competitive exam

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Basics of Agronomy


Latin word: Agronomy – Greek word.

• Community development programme – 1952.

• Sharbati Sonara obtained from Sonara – 64 with gamma rays.

• Jaganath (Rice) obtained from T – 141 with X – rays.

• Aruna (Castor) obtained from HC – 8 with thermal fast neutrons.

• Intensive Area Development Programme (IADP) also known as “Package Programme” (1960).

• 1875 – Indian Meteriological Department (IMD) – Pune.

• 1880 – First report of Famine Commission.

• 1898 – Second report of Famine Commission.

• 1901 – Third report of Famine Commission.

• 1903 – Imperial Agricultural Research Institute, Pusa, Bihar.

• 1928 – Royal Commission on Agriculture.

• 1929 – ICAR

• 1936 – IARI shifted to Delhi.

• 1966 – HYVP

• 1967 – Multiple Cropping Programme (MCP).

• 1969 – National Demonstration Programme (NDP).

• 1972 – ICRISAT.

• Central Plantation Crops Research Institute – Kasargad.

• ICARDA – Syria; CIMMYT – Mexico; IRRI – Manila; IPRI – Peru; ICTA – Cali, Columbia; IITA – Ibadan, Nigeria.

• Meteriology – Greek word.

• Meteriology – Science of atmosphere;

• Weather – State (or) condition of the atmosphere at a instant time.

• Climate – Summation of weather conditions over a longer period.

Structure of atmosphere

1. Troposphere – Thicker at equator and thinner at poles and most stable.

2. Tropopause – Present between troposphere and stratosphere.

3. Stratosphere – Includes ozone layer (or) ozonosphere. a. It is the seat of all photochemical reactions in the air.
Solid portion of earth – Lithosphere.

• Ionosphere is the most unstable layer in the atmosphere.

• The upper part of the atmosphere is called as “Magnetosphere”.

• Altitude – Height; Latitude – Imaginary line horizontally connecting the East and west.

• Longitude – Imaginary line connecting the North & South poles. It is useful for calculating of “Local mean time” (LMT).

• For calculating Greenwitch mean time (GMT) – 00 longitude.

• For IST – 82.50E ; Albido = Reflected radiation /Insulation radiation

• Source of heat to the plants – Infra red rays.

• 42% insulation returned to the space. 58% usable insulation.

• The average amount of energy available at the outer limits of the atmosphere is known as “Solar Constant”. Value of I.C. is 1.94 ca/cm2/min.

• Short day plants Maize, Soyabean, Tobacco.

• Long day plants Sugarbeet, Wheat, Barley.

• Day neutral plants Sunflower, Cotton.

• In temperate regions the Southern Slopes show better growth of crops than northern slopes due to the direction of light.

• Solar radiation – Pyranometer (or) Pyrheliometer – Ca1/Cm2/min.

• Duration of light – Campbell Stokes sunhine recorder – hours/day.

• Intensity of light – Lux meter – LUX.

• Wave length absorbed in PS Violet – blue & Orange – red.

• The most harmful effect of high light intensity is the “Solarisation” because of photo oxidation.

• Radiation – Transmission of heat without medium.

• Convection is the most effective for heat transfer in atmosphere.

• The condition in which the abrupt rise instead of fall in temperature occurs in the air is known as “Inversion”.

• Maximum temperature 1.00 – 4.00 PM, Minimum temperature 1.00 – 6.00 AM

• The end of July – highest temperature. The end of January – Lowest temperature

• C = (F – 32) * 5/9; F = (9C/5) + 32 • Six’s Thermometer records both Max. and Min. temperature.

• Thermograph – Continuous recording of air temperature.

• Dry bulb thermometer – current air temperature.

• Isotherms – are the lines connecting the places that have equal temperature.

• The decrease in temperature with increase in altitude in the air is known as “Vertical Temperature gradient”. It is expressed as “Lapse rate”.

• The rate at which temperature decreases with increase in altitude of air is known as “Lapse rate”.

• The value of LR is 3.50F per 1000 feet (or) 6.50C per Km.

• The rate at which temperature changes due to change of pressure is called as “adiabatic lapse rate”. The value is 5.50F/1000 (or) 100C per Km.

• The plant goes to “Starvation” due to high respiration rate.

• Suffocation – Ice in contact with plant roots inhibit the diffusion of CO2 and respiratory products.

• Heaving – Injury to plant is caused by lifting upward of the plant along with soil from its normal position.

• Vertically moving air columns are called as “Currents”.

• Winds are mainly caused due to “pressure gradient”.

• The difference in pressure between two places at the same elevation is called “Horizontal pressure gradient”.

• The direction from which wind blows is called “Windward”.

• Clock wise direction of wind movement – Veering wind; Anticlock wise direction of wind movement – Backing wind.

• Wind direction – Wind vane, Speed Robinson cup anemometer Anemograph – Both direction and Speed.

• The lines connecting the points having equal wind speed are called – “Isotechs”.

• Trade winds – It is the movement of air in lower layer of atmosphere. The winds that are flowing from horse latitudes to towards doldrums (Equator) in both the hemisphere are called trade winds.

• Antitrade winds Movement of air in the upper layer of atmosphere from equator to towards North and South poles.

Water vapour present in the air R.H = X 100 Water vapour required for saturation

• Instrument used for measurement of R.H. are called “Psychron (or) Hygrometer.

• Wet & dry bulb thermometer – R.H. in field. ‘

• Hair hygrometer – Inside room.

• Hydrologic cycle It is the continuous circulation of water between atmosphere, lithosphere, hydrosphere.

• Rate of evaporation expressed as mm/day.

• Under equivalent conditions ocean water will evaporate 5% more slowly than fresh water.

• Measurement of evaporation – USWB Class A open pan evaporation. In free water surface.

• Sunken screen evaporimeter In a cropped field.

• Hygroscopic particles can act as nuclei for condensation.

• Most important hygroscopic nuclei in the atmosphere are sea salt (NaCl) nitric oxide.

• Dew point: The temperature at which saturation occurs or condensation temperature.

• Dew: Deposition of liquid water droplets on the surface of cooled objects.

• Fog: Aggregation of minute droplets of water suspended in the air near the surface of earth. It is also called as “Low Cloud”.

• Haze: Smoke and dust mixed with fog.

• Frost: Same as dew but in dew condensation above freezing point. But in frost condensation below freezing point.

• Cloud: Same as fog. But in higher altitudes.

• There are 3 basic clouds forms.

1. Cirrus (Fibrous (or) Feathery)

2. Cumulus (Heaped manner) – resembles like cauliflower.

3. Stratus (Layers).

• It a basic cloud from above its normal height then the cloud will be thin prefix “Alto”.

• If any cloud is associated with precipitated prefix or suffix “Nimbus”.

• High clouds Cirrus, Cirro cumulus (Sea shores), Cirro Stratus.

• Middle clouds Alto cumulus, Alto Stratus (typically water).

• Low clouds Stratus, Nimbo Stratus and Strato cumulus.

• Clouds with vertical development Cumulus, Cumilo nimbus.

• Sky cover expression : clear – <1/10; Scattered – 1/10 to 6/10; Broken – 6/10 to 9/10; Over cast – 9/10.

• Obscured Sky and Clouds are completely covered with Fog and Smoke.

• Southwest monsoon 7th June to 26th September.

• Northeast monsoon 27 th September to 31st January

• Hot weather period 1st February to 6th June

• Precipitation in the from of liquid :-
• 1. Rain → droplets between 0.5 mm to 4mm Rain > 0.5mm

• 2. Drizzle → Rain droplets < 0.5mm -light rains.

• 3. Mist → Rain droplets completely evaporates before reaching the ground.

• 4. Glaze → Rainfall on objects into a sheet (or) coating of ice.

• 5. Rime → Freezing fog.

• 6. Snow → White crystals of frozen water.

• 7. Sleet → Frozen (or) partly frozen rain.

• 8. Holi → Icepieces.

• Isohyets → The imaginary lines connecting the places receiving same amount of rain.

• Measurement of rainfall – Rainguage

1. Coastal Andhra : Punasa – Early kharif Peddapanta – Late kharif Pyru – Rabi

2. Rayalaseema : Mungari – kharif Hingari – Rabi

3. Telangana : Abi – kharif Tabi – Rabi
• In coastal districs paddy growing season from June to Novermber is called as “Sarva” while paddy growing from October to March is called “Dalwa”.

• Low pressure areas are called “Depressions”.

• Tropical cyclones are violent storms. These storms in West Indian water are known as “Hurricanes”. In the East Indian and Japanese water are known as “Typhoons” and in the Indian ocean they are called “Cyclones”.

• Prediction of the weather for the next few days to follow is known as “Weather forecasting”.

• Brief report on weather conditions in coded form is known as “Synoptic report”.

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