FACTORS AFFECTING CROP PRODUCTION.ppt

FACTORS AFFECTING CROP PRODUCTION
Internal factors (Genetic factors) of CROP PRODUCTION
External factors of CROP PRODUCTION
Climatic factors of CROP PRODUCTION
Edaphic Factors (Soil) of CROP PRODUCTION
Biotic Factors of CROP PRODUCTION

1. K.VANANGAMUDI
Formerly Dean (Agri.), TNAU
Dean, AdhiparasakthiAgricultural College, Kalavai
Professor & Head, Seed Science & Technology
Tamil Nadu Agricultural University,
Coimbatore, Tamil Nadu

3. •Resistancetolodging
•Tolerancetodrought,salinity,flood,pestsand
diseases
•Highyieldingcapacity
•Chemicalcompositionofgrains(Oilandprotein)
•Qualityofgrain(Fineness,coarseness)andstraw
(Sweetness,Juiciness)

4. Climaticfactors
•50%ofyieldisattributedbyclimaticfactors

5. 1. Precipitation
•Includesrainfall,snow,hail,foganddew.
•Inheavyandevenlydistributedrainfallareas–
Riceinplains
Tea,coffeeandrubberathigherelevation
•Inlowandunevendistributedareas,dryfarming
iscommon
•Droughtresistantcrops-Pearlmillet,sorghum,
minormilletsandpulses

6. 2. Temperature
•Measureofintensityofheat
•Cropsneedrangeoftemperature:15-40˚C

7. Temperature for different crops
Crops Minimum
temperature
(°C)
Optimum
temperature
(°C)
Maximum
temperature (°C)
Rice 10 32 36-37
Wheat 4-5 20 30-32
Maize 8-10 20 40-43
Sorghum 12-13 25 40
Tobacco 12-14 29 29-35

8. 3. Atmospheric humidity (RH)
•Invisiblewaterinair
•RH–Ratiobetweenamountofmoisturepresentin
airtosaturationcapacityofairatparticular
temperature.
•Measured by thermo hygrograph or Psychrometer
•OptimumRHformostofcrops:40-60%
•HighRH-Outbreakofpestsanddiseases.

9. 4. Solar radiation
•PAR–Photosyntheticactiveradiation:400-700
nanometers–Optimumforcropproduction
•Phototropism–Plantresponsetolightdirection
Eg.Sunflower
•Photointensive–Seasonbound

10. Photoperiodism
Plant response to day length

11. Photoperiodism
•Examples
•Shortday
Eg.Rice,sunflower,cotton
•Longday
Eg.Barley,oats,carrot,cabbage.
•Dayneutral
Eg.Tomato,maize

12. 5. Wind velocity
•Tocarrymoisture,precipitationandheat
•Suitablewindmovement:4-6km/hr

13. 6. Atmospheric gases
•CO
2–0.0407%
•O
2–21%(20.95)
•N
2–78.8%,Argon–0.93%andOthers–0.02%
•CO
2–EssentialforPhotosynthesis
•O
2–EssentialforRespiration
•Nitrogenfixation
Symbiotic(Rhizobium)
Nonsymbioticfreelivingbacteria(Cyanobacteria,Azotobacter)
•N-Alsosuppliedbylightningandrainfall
•SO
2,CO,CH
4,chlorofluorocarbons-Toxictoplants.

14. Q & A
Photosyntheticactiveradiationessentialforcarbohydrate
productionis
a.0.4-0.7µ b.0.2-0.3µ
c.0.3-0.5µ d.0.7-0.9µ
Oxygencontentinatmosphereisabout
a.20% b.20.95%
c.21% d.20.87%
Exampleofshortdayplantis
a.Rice b.Maize
c.Barley d.Oats
AssociativeSymbioticN-fixeris
a.Rhizobium b.Azospirillum
c.Azotobacter d.Mycorrhiza

15. 1.Soilmoisture(water)
•Helpsinchemicalandbiologicalactivitiesofsoil
includingmineralization.
•Moderatessoiltemperature
•Regulatesavailabilityandmobilityofnutrients.
•Moistureismoreinclaysoilthansandysoil.

16. 2.Soilair
•Riceneedslowlevelofoxygenduetowaterlogging
condition.
•HighO2-Potato,tobacco,cotton,linseed,tea,legumes
3.Soiltemperature
•Affectsphysicalandchemicalprocessofsoil
•Regulatesabsorptionofwaterandnutrients.

17. 4.Soilmineral
•SourcesofplantnutrientslikeCa,Mg,S,Mn,Fe,
K
5.Soilorganicmatter
•Suppliesmajorandmicronutrients.
•Improvessoiltexture.
•Increaseswaterholdingcapacity.
•Sourceoffoodformicroorganism

18. 6.Soilorganisms
•Helpsindecompositionofraworganicmatter
•N2fixationbymicrobes
7.SoilpH-Soilreaction
•LowpHsoilisinjurioustoplant,duetohighiron
andaluminiumtoxicity.

20. 1. Plants
•Competitionformoisture,nutrients,sunlight.
•Complementaryeffectorsynergisticeffect.
Eg.Cerealsandlegumes.
•Competitivecrops
Strigainsorghumandsugarcane
Orobrancheintobacco
Cuscuttainlucerne

21. 2.Animals
•Soilfauna:Protozoa,nematodes,snails,insects.
•Insectsandnematodescausescropdamage
•Honeybeesandwasphelpsinpollination
•Borrowingofearthwormshelps
Aeration
Drainage
Organicmatterdecomposition
•Largeanimalcausedamagetocrops.
•Eg.Animalgrazing

23. •Topography-natureofthesurfaceearth(Leveled
andslope)
•Increaseinlatitudedecreasesthetemperatureand
precipitation.
•Steepslope-Favoursrunoffandlossoftopsoil
(Nutrients)
•Slopeexposedtolowintensityoflightandstrong
windresultsinpooryield.

24. •Inclinationtowardsfarming
•Landholderschooseonlyfoodandfoddercrops
•Nonavailabilityofresistancevarietiesdrought,
pestanddisease
•Economicconditionoffarmers:Marginal,
mediumandsmallfarmersfindinabilityin
resourcemobilization.

25. Q & A
Synergisticeffectisobservedin
a.Cerealsandlegumes
b.Cerealsandweeds
c.SugarcaneandStriga
d.Bothbandc
Cropsrequiringhigheroxygencontentis
a.Sugarcane b.Cotton
c.Legumes d.Bothbandc
Lowandunevenrainfallisacommonin
a.Semiarid b.Drylandfarming
c.Wetlandfarming d.Gardenland