Cereals 2024 Week 9 Lecture Nitrogen Nutrition Part 2 Handout

Question 1

Recovery of Applied N

2 things:

Answer 1

• Efficiency of fertiliser N uptake
• Efficiency of Organic N (slurry etc) uptake

Question 2

Crop nitrogen uptake for North Dublin site
- soil N and fertiliser N components
Slide 3 Explain what you see in graph

Answer 2

As the rate of N increased, the soil N uptake increased

-Soil N uptake= 95kg/ha

-Efficiency of fertiliser N recovery - 0.58 (58%)

Question 3

1- What is used in Ireland and Britain as the basis for fertiliser N
recommendations?

2- What is it based on? (3)

3- Whats the scape used for tillage crops and what does it mean?

Answer 3

1- Nitrogen Index System for Cereals

2- based on the N requirement of each tillage crop
taking into account
– the previous crop
– manuring history of the field
– soil type

3- the N index uses 1-4 scale for tillage crops

– Index 1 = small release of soil N
– Index 2 = medium release of soil N
– Index 3 = large release of soil N
– Index 4 = very large release of soil N

Question 4

if your soil is in index 1 what previous crops could of been sown? (3)

Answer 4

1-Cereals
2-Maize
3-Veg receiving less than 200kg/ha nitrogen

Question 5

if your soil is in index 2 what previous crops could of been sown? (10)

Answer 5

Sugar beet
Fodder beet
Potatoes
Mangels
Kale
Oilseed Rape
Peas
Beans
Leys (1-4 years) grazed or cut and
grazed.
Swedes removed

Question 6

If your soil is index 1…

Answer 6

The fifth tillage crop following permanent
pasture. For subsequent tillage crops
use the continuous tillage table

Question 7

If your soil is index 2…

Answer 7

The 3rd or 4th tillage crop following
permanent pasture. If original permanent
pasture was cut only, use index 1

Question 8

If your soil is index 3…

Answer 8

The 1st or 2nd tillage crop following
permanent pasture (see also index 4). If
original permanent pasture was cut only,
use index 2.

Question 9

If your soil is index 4…

Answer 9

The 1st or 2nd tillage crop following very
good permanent pasture which was
grazed only

Question 10

Fertiliser Recommendations follows what?

Answer 10

the
code of good agricultural practice

Question 11

What does the
code of good agricultural practice require?

Answer 11

this requires that nutrient supply be
matched to crop demand, both in terms of
the quantity applied and the time of
application relative to the crop yield, soil
and climatic conditions

Question 12

Fertiliser Nitrogen Recommendations (kg/ha) for
Winter Cereals on medium soil types
(where proof of higher Yield is not available)
Slide 9

Fertiliser Nitrogen Recommendations (kg/ha) for
Spring Cereals on medium soil types
(where proof of higher Yield is not available)
Slide 10

Learn both of them write it out

Question 13

Nitrogen Use in Malting Barley:

1- What will fertiliser do?

2- How much fert do you apply?

Answer 13

1- Fertiliser Nitrogen use will
increase yield

2- e.g. apply
120-135 kg/ha for a 7.5
t/ha grain yield

Question 14

What N% of grain does making beer need?

An extra what kg/ha can be
applied to avoid low grain
protein (if advised)

Answer 14

However moderate grain N%
is required for high quality
malt for making beer

20kg/ha

Question 15

Malting Barley :
Effect of +40 kg N on
Grain Protein % - Trends over 3 Years

Answer 15

Year 1-
Standard N yield= 9.5
+40 kg/N= 10.5

Year 2
Standard N yield= 10
+40 kg/N= 11

Year 3
Standard N yield= 9.1
+40 kg/N= 9.9

Question 16

Nitrogen Use in Milling Wheat: