2. SEMINAR
ON
Crop weather modeling advantages and
modeling in
GROUND NUT
Presented by
P Ganesh
RAM/15-04
Submitted to
Dr .D. Srilatha madam
professor
3. why should we study crop weather modeling ..???
Weather is one of the important components influencing agricultural production and
productivity
As weather assumes significance in nearly every phase of agricultural activity from
the preparatory tillage to harvesting and storage and by interfering with routine
agricultural operation and plant protection measure, hence success or failure of
farming is intimately related to the prevailing weather conditions.
The extent of Influence of weather on crop growth mainly depends on the crop
growth stage.
The relationship between weather and crop production has been under stood through
crop weather modeling The understanding of the interactions between weather, soil,
management practices etc
4. Terms used in modeling
Model : A model is a schematic representation of a system or a set of equations, which
represents the behavior of a system
.
Simulation: Is the imitation of the operation of a real-world process or system over
time. It is also defined as “Reproducing the essence of a system without
reproducing the system itself”.
Calibration: the process of adjustments in model parameters to make the model to
behave as per the defined system.
Validation: the comparison of predicted values of model with the results from
experiments. There may be differences between experimental output and simulated
output due stresses which were not considered during simulation. Validation is used
as evaluation with emphasis on usefulness and relevance of the model.
5. Uses of crop weather models
Crop system management: to evaluate optimum management practice. viz., Fertilizer,
Irrigation: &Seed rate
Yield gap analysis
Yield prediction and forecasting.
Evaluation of climate change
Useful for solving various practical problems in agriculture.
Are resource conserving tools.
Can be used in precision farming studies.
Are very effective tool for predicting possible impacts of climatic change on crop growth and
yield.
Helps in adaptation strategies, by which the negative impacts due to climate change can be
minimized
6. Weather Parameters:
Solar radiation Temperature Rainfall & wind
Solar radiation
The visible part of solar radiation affects the growth and development of all plants
both directly or indirectly.
Therefore light of correct intensity, duration and quality is necessary to normal plant
development.
Light plays role in distribution of photosynthates among different organs of plants
Solar radiation is very much important during the critical stages of plant growth.
Solar radiations play a vital role in photosynthesis.
7. Temperature
Temperature is defined as the measure of kinetic energy of the molecules
There are many plant processes governed by the temperature.
(a) chemical solubility depends up on the temperature.
(b) All the physical, chemical and biological processes are regulated by the
temperature with in the plants.
(c) The enzymes and their functions are also regulated by the temperature.
(d) The diffusion of different gases present in atmosphere or soil is also
governed by the temperature.
Each crop is known to have its own optimum, maximum and minimum
temperature conditions called as cardinal temperatures.
8. Wind:
Horizontal movement of air is defined as wind, while in vertical direction, it is
known as current.
intake of carbon dioxide depends on its concentration in the atmosphere and its
delivery to the leaf
At higher and lower rates of wind speed photosynthesis decreases
Rainfall:
Solid or liquid form of atmospheric water is known as rain fall.
Cells contain 80-90 % water this only tells what water is ??
Being universal solvent, it increases the chemical activity of the compound in the plant.
Rain water increases soil moisture.
Both, scanty as well as excess rain fall is harmful for plants.
10. General Crop Growth Model contains …
Inputs Process Output
Weather (Temperature,
Rainfall, solar radiation)
Soil Parameters (Texture, depth,
soil moisture, soil fertility)
Crop Parameters (Phenology,
physiology, morphology)
Management (DOS, irrigation,
fertilizer)
Phenological
Development
CO2 Assimilation
Transpiration
Respiration
Partitioning
Dry matter Format
Biomass, LAI, Yield
Water Use
Nitrogen Uptake
11. The decision support system for agro technology transfer (DSSAT) has been in use for the last 15 years by researchers worldwide
12. Groundnut or Peanut or Monkeynut or Earth nut
Groundnut is an important oil and protein source to a large portion of the population in
Asia, Africa and the America.
It is a self -pollinated, annual, herbaceous legume.
Groundnut, king of vegetable oil seeds in India, occupies pre-eminent position in
national edible oil economy,
Climate:
Groundnut is predominantly a crop of the tropics.
The commercial production are between latitudes 400N and 400S and up to an attitude
of 1065 m
Rainfall
The crop can be grown successfully in places receiving a minimum of 500 mm and a
maximum of 1250 mm.
500 – 700 mm rainfall during crop period is ideal for groundnut production.
Rainfall should be adequate during flowering and pegging stages.
13. Temperature:
• Soil temperature <18°C delays emergence of seedlings. The embryo is
killed above 54°C
• G.nut performs well in dry temperature range b/n 24 & 33°C but it can
survive up to 45°C
• Ideal temperature for reproductive stage is b/n 24 – 27°C
• Rate of pod growth will be maximum b/n 30°C & 34°C .
Light :
• Groundnut is day neutral plant
• Flowering phase is more sensitive to reduced light intensities.
• In the absence of soil moisture stress, clear days have greatest potential to
get high yield
14. BAMnut modal
It was an improvement of the original PARCH-based model
The model was designed with functional relations derived from glasshouse and
growth room experiments
BAMnut simulates dry matter production and pod yield through numerical
integration
BAMnut needs daily weather data as an input.
The minimum inputs for BAMnut are solar radiation, minimum and maximum
temperatures, and rainfall.
Depending on the availability of the resources light and water, the production is
either light limited or water limited
Light limited growth (LLG) is calculated from incoming solar radiation and the
fraction of this solar radiation intercepted by green leaves.
Water limited growth (WLG) is calculated from potential water uptake rates and
the amount of available water in the rooting zone.
LLG and WLG are then compared, and actual growth taken as the minimum of
the two
15. water balance growth under water limited condition is represented in the left part of the fig.
the right part of the fig represent the potential growth of the shoot and pod L is the leaf area
index leaf w. pod w. Root w.& shoot W represent the dry weight of each
Groundnut
16. Modeling Yield Response of Groundnut to Deficit Irrigation at
Different Growth Stages by FAO CROPWAT
Agricultural Research Station,Tamil Nadu Agricultural University, G. Thiyagarajan et.al
17. Conclusions………..
These modals bring the knowledge of science in to a real object.
All these modals help to estimate yield and forecasting not exactly
the same but nearer to the observed values Research has to be
strengthen to get accurate systems that predict real world.
Farmer has to get benefit out of this predicted data then only it
bears fruits.
For this extension system has to be stretched
