Transcript Module V: Sorghum Plant Nutrition Virtual Academy for the Semi Arid Tropics Lesson 2.

Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
After successful completion of 3 Units in this
Lesson, you will be able to answer:
1. What is the role of nitrogen, phosphorus, and
potassium in plant nutrition in general, and in
sorghum crop in particular?
2. What is the recommended rate and method of
nitrogen application to sorghum?
3. What is the recommended rate and method of
phosphorus application to sorghum?
4. How do you decide whether to apply potassium
or not?
5. What is the recommended rate and method of
application of potassium to sorghum?
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
The 3 Units in this Lesson are:
Unit 1: Nitrogen Nutrition
Unit 2: Phosphorus Nutrition
Unit 3: Potassium Nutrition
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
After successful completion of this Unit, you
will be able to answer:
1. What is the role of potassium in plants?
2. How do you decide whether to apply potassium
or not?
3. What is the recommended rate of potassium
application to sorghum crop?
4. What is the method of potassium application to
sorghum?
5. Under what conditions potassium is applied as
top dressing?
6. Which potassic fertilizer is useful to sorghum
crop and why?
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
Though potassium application is not
regularly practiced, it plays equally
important role as nitrogen and
phosphorus in plants for their growth
and development.
Potassium is involved in the plants to:
• provide resistance to insect
pests, diseases, and water
stress;
• use the water economically;
• improve the quality of the crop
produce.
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
Potassium is to a plant what breaks are to
a car.
Good brakes are a must for safe journey to
reach the destination and so is potassium
for good quality crop produce.
Usually it is considered that most of the
Indian soils are rich in potassium.
Is this true in case of the soil in your field?
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
Make sure that the soil will meet the
potassium needs of the sorghum crop in
your field through soil testing.
If the soil test reveals that the available
potassium is less than 150 kg of K2O/ha,
then there is a need to apply potassium in
that field.
Normally, about 30 to 50 kg K2O/ha will be
adequate for sorghum sown in soils deficient
in potassium.
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
Potassium uptake is greater in the early part
of sorghum growth than that of nitrogen and
phosphorus.
So, potassium fertilizers are usually applied
in one dose at the time of sowing.
However, in light soils, to minimize the loss
of potassium due to leaching under heavy
rainfall conditions, apply potassium in two
splits doses.
In such cases, the top dressing is to be done
30 to 40 days of sowing.
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
Unit 3: Potassium Nutrition
Potassium fertilizers are placed along with
nitrogen and phosphorus either in the seed
furrows or side dressed before sowing.
Potassium is top dressed along with
nitrogen application, if any. The fertilizers
are applied near the rows of the sorghum
plants and incorporated either by
intercultivation or by manual weeding.
There should be sufficient moisture in the
soil at the time of this top dressing of
fertilizers.
Course on Sorghum Production Practices
Module V: Sorghum Plant Nutrition
Virtual Academy for the Semi Arid Tropics
Lesson 2. Importance of Primary Nutrients
With this, the Unit 3 on Potassium
Nutrition, and this Lesson 2 on the
Importance of Primary Nutrients
concludes.
The next Lesson is about the
importance of other plant nutrients
for sorghum.
The last lesson is about application
of manures and fertilizers in
sorghum.
Select Lesson 3 from Module V contents
Course on Sorghum Production Practices