After completing this Lesson, you have learned to answer:

1
Module 7 Interpretation of weather for farm
operations.
Virtual Academy for the Semi Arid Tropics
Modules

After completing this Lesson, you have learned to
answer What are the optimum
conditions of temperature, soil
moisture in terms of previous rainfall receipt,
present rainfall, and wind for different farm
operations like land
preparation, sowing, transplanting, fertili
zer application, irrigation, spraying and
dusting, harvesting?
Course on Crop-Weather Relationships
2
Farm operation Temperature Soil moisture
Rainfall Wind Land preparation gt 0OC (soil)
80 of FC lt 1 mm 45 kmph Sowing
gt 4.5OC (soil) 40-80 of FC lt 1mm
30 kmph Transplanting gt10OC (soil)
60-90 of FC - 25 kmph
FC Field Capacity (Field capacity refers to the
moisture content in the soil when
the soil is fully saturated with moisture and
the downward movement water has
virtually ceased.)
3
Farm operation Temperature Soil moisture
Rainfall Wind Fertilizer application
gt10OC (soil) 30-80 of FC lt 1 mm 30 kmph
Irrigation -
lt 50 of FC No rain 25
kmph Spraying and dusting - lt 90 of FC
No rain lt25 kmph Harvesting - lt
90 of FC No rain - FC Field
Capacity
4
Thresholds for
spraying Wind speed lt 8 kmph Ideal Wind speed
8 - 15 kmph Good Wind speed 16 - 22
kmph Fair Wind speed 23 - 28 kmph Marginal
5

• Air temperature between 5oC and 27oC is
  ideal for application of insecticides,
  fungicides, herbicides, and fertilizer. At
  higher temperatures there could be
  evaporation losses.
• Any rainfall before 6 hours of spraying
  or soil application may result in dilution
  or washing away of insecticides,
  fungicides, herbicides, and fertilizers.

6
Module 7 Interpretation of weather for farm
operations.
Virtual Academy for the Semi Arid Tropics
Exercise
Modules

This concludes the Lesson on Interpretation of
weather for farm operations - in this Module.
If you would like to check your understanding
about Interpretation of weather for farm
operations, click Exercise button.
Course on Crop-Weather Relationships
7
Module 7 Interpretation of weather for farm
operations.
Virtual Academy for the Semi Arid Tropics
Modules

With this Module, the Course on Crop-Weather
Relationships concludes. To learn more about
this subject, you may review the internet links
given in the next screens. To review this
Course, click on Modules button and select the
Module to review.
Course on Crop-Weather Relationships
8
Module 7 Interpretation of weather for farm
operations.
Virtual Academy for the Semi Arid Tropics
Modules

You may click on the following internet sites to
learn more about weather and its relationship
with crop production. http//www.crseo.ucsb.edu/e
srg/IOM2/Monsoon_def.html http//www.crseo.ucsb.e
du/esrg/IOM2/Mechanisms.html http//science.howst
uffworks.com/sweat.htm http//atmos.es.mq.edu.au/
aws2/hardware/YWinSenS.html
Course on Crop-Weather Relationships
9
You may click on the following internet sites to
learn more about weather and its relationship
with crop production. http//www.millville.org/Wo
rkshops_f/Rowe_Science/clouds_f/cldtext/clouds1.ht
ml http//www.agrometeorology.org/operational/ins
truments.html http//www.krishiworld.com/ http
//extension.oregonstate.edu/mg/botany/env_factors.
html
10
You may click on the following internet sites to
learn more about weather and its relationship
with crop production. http//www.agroecommerce.co
m/Agroecommerce/BriefInfo/Crops/RiceInfo.asp http
//ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/home.rxml
http//www.usatoday.com/weather/tg/whighlow/whig
hlow.htm http//kids.earth.nasa.gov/archive/air_p
ressure/index.html
11
Module 7 Interpretation of weather for farm
operations.
Virtual Academy for the Semi Arid Tropics
Modules

You may click on the following internet sites to
learn more about weather and its relationship
with crop production. http//www.imd.ernet.in/ h
ttp//www.ncmrwf.gov.in/ http//www.cln.org/theme
s/clouds.html
EXIT
Course on Crop-Weather Relationships