marked advantages of potassium nitrate under water ... · marked advantages of potassium nitrate...

Oded Achilea,

Marked advantages of

POTASSIUM NITRATE

under water scarcity & salinity

Worldwide water scarcity –

supply aspect

Source: “Catastrophic Fall in 2009 Global

Food Production”by Eric deCarbonnel , 2009

University of Oklahoma, Health Sciences Center (2005)

Worldwide water scarcity –

demand aspect

Since 1950

* World population

increased by 100%

* Water consumption

increased by 600%

Irrigation must be made more efficient and

more sustainable

Nutrition techniques must be harnessed to

increase WUE

Two cardinal conclusions

Worldwide water scarcity –

Let’s join efforts

Water

use

efficiency

Water Use Efficiency

Two independent plant functions are involved:

Dry (or fresh) matter produced

Water transpired=

Water management

Biomass production

The Roles of Potassium

Water Use Efficiency

Potassium is a pre-requisite for normal building

process of plant structure

K & Biomass management

Potassium is a pre-requisite for normal functioning of all plant

biochemical and physiological systems 60 enzymes!

K maintains turgor, thus reducing lodging

and enhancing harvesting efficiency

K & Biomass management

Conclusion:

Under normal growing conditions –

The higher the K, the higher biomass production

K & Biomass management

Potassium status of the plant determines the recovery

rate from a drought stress

Skogley, 1976

Severe K deficiency

Moderate K deficiency

Duration of exposure to hot wind (minutes)

K & Water management

0

0.5

1

1.5

2

2.5

3

0 2 4 6 8 10 12 14 16 18 20

Low-K nourished

Normal-K nourished

Time of day

Arqero, Barranco & Benlloch (2006)

Potassium deficiencyincreases stomatal conductance in olive trees

* At a typical summer day during the experiment period (93d.);

Plants under drought regime; Cultivar: ‘Chemalali de Sfax’

Dawn Sunset

During one day

Potassium deficiency –

increases transpiration rate in olive trees

Benlloch-Gonzalez, Arqero, Fournier, Barranco

& Benlloch (2008)

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

0 10 20 30 40 50 60

Low-K nourished

Normal-K nourished

Cultivar: „Lechin de Granada’

Days from onset of dry period

During the season

Arqero, Barranco & Benlloch (2006)

0

2

4

6

8

Irrigated Drought

Low K Normal K

Water-use

efficiency*

(gDW/L)

* An integration of entire experiment period (93d.);

Cultivar: ‘Chemalali de Sfax’

a

ab

b

Potassium deficiency –reduces Water Use Efficiency in olive trees

Fournier, Roldan, Sanches, Alexandre & Benlloch (2005)

DW (g/plant) K in leaves (umol/g

FW)

WUE (gDW/l)

[K] =0.1 mM

[K] =2.5 mM

0.13

a

0.14

a

58.4

a

110.2

b

1.89

a

2.57

b

Plants were grown for 6 days in nutrient solution with 0.1 or 2.5 mM K+

Potassium deficiency –decrease Water Use Efficiency in sunflower plants

And other crops too:

Faba beans (Abdel-Wahab & Abd-Alla, 1995)

Sugar cane (Sudama & al., 1998)

Rice (Tiwari et al., 1998)

A similar pattern governs both crops

Olive trees (perennial, slow growing species) and in

Sunflower (annual, fast growing species)

Potassium deficiency decrease Water Use Efficiency

Benlloch-Gonzalez, Arqero, Fournier,

Barranco & Benlloch (2008)

Abscisic acid (ABA) has a special role in plant stress

management.

Increased ABA levels stimulate the release of K

from the guard cells, resulting in stomatal closure.

Ethylene is involved too.

PGR’s are involved too in potassium management

and stomatal functioning

Conclusion:

Under normal growing conditions –

The higher the K, the higher the WUE

The roles of Nitrate

Lips, Leidi, Silberbush, Soaresh & Lewis, 1990

Conclusion:Nitrate-nitrogen is markedly more efficient than

ammonium-nitrogen, regarding production of

dry matter, especially under K deficiency

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.1 1 5

Ammonium

Nitrate

Biomass

)gDM / plant)

K+ level in medium solution (mM)

Comparative effects of Nitrate and Ammonium on photosynthesis &

biomass production in wheat

2

4

6

8

10

0.1 1 5

Ammonium

Nitrate

Photosynthesis

)mg CO2 / shoot / h)

Nitrate & biomass management

K+ level in medium solution (mM)

Comparative effects of Nitrate and Ammonium

on transpiration rate of wheat

Lips, Leidi, Silberbush, Soaresh & Lewis, 1990

Nitrogen was applied as calcium-Nitrate or Ammonium-sulfate, @: 4 mM of N,

at various rates of K, as potassium sulfate. Wheat seedlings were grown for 21 days.

400

500

600

700

800

0 1 2 3 4 5

Ammonium

Nitrate

Transpiration

)ml water / gDM)

K+ level in medium solution (mM)

Nitrate & water management

Effects of Nitrate and Ammonium on WUE in wheat

Lips, Leidi, Silberbush, Soaresh & Lewis, 1990

Nitrogen was applied as calcium-Nitrate or Ammonium-sulfate, @: 4 mM of N,

at various rates of K, as potassium sulfate. Wheat seedlings were grown for 21 days.

0.1

0.3

0.5

0.7

0.9

0.1 1 5

Ammonium

Nitrate

WUE

)gDM / L water)

K+ level in medium solution (mM)

Nitrate & WUE

Conclusion:

Under normal growing conditions –

The higher the Nitrate, the higher the WUE

The effect of

POTASSIUM NITRATE

The effect of potassium nitrate on

size distribution of orange fruits

0% 0%2%

11%

23%

27%

12%

4%

0%0% 0% 0%

3%5%

35%

16%

1% 0%

20%

41%

-5%

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

50 55 60 65 70 75 80 85 90 95

Mean fruit diameter (mm)

Fru

it s

ize

sh

are

in

tre

atm

en

t

Control- 0 application Grower's practice

Bonus-npK Multi-K 3 X 5%

„Jaffa’ oranges, in Israel, 2002

Increasing Mango trees productivity by spraying

Potassium Nitrate, via the increase in WUE

1

1.5

2

2.5

3

3.5

4

4.5

Julie Graham Tomi Atkins

Control

PN 6% - May

PN 6% - June

WUE

)mM CO2 / MH2O)

Cultivars tested

Spraying treatments

a a a

b

b

b

a

ab

Shongwe & Roberts-Nkrumah, Trinidad, 1996

b

Kafkafi, Walerstein & Feigenbaum, 1971

WUE

mL water /

g fresh fruit

Yield

(g/plant)

N (g/plant)N form (%)

Amm.

Nitrate

Multi-K(NO3- : NH4

+)

23**2550*06.3100 : 0

28**1980*4.46.370 : 30

29**1200*8.76.363 : 37

34**1000*13.26.359 : 41

23**3430*012.6100 : 0

* Significance at 0.1% probability; ** At 1% probability

Increased of WUE by nutrigation of

Potassium Nitrate, in Tomatoes

Potassium Nitrateincreases WUE

Hence:Every m3 of water

can produce more if combined with

Potassium Nitrate

The problem of man-made salinization

Severely salinated fields in central California

Washington State University (2001)

Country Badly salinized as

% of irrigated area

India 37 – 60

Iraq 50

Egypt 30

Pakistan 25

U.S. 23

Australia 20

China 15

Pakistan 14

Israel 13

Irrigation-induced salinization

Most frequent ions involved in salinity situations are:

Anions: Cl- , SO4-2, B-

Cations: Na+

Elevated EC

Specific toxicity

The mechanism of salinity damage

A simplified model

Photosynthesis

The K+ shuttle facilitates NO3-

movement upwards, and malate-

downwards.

Proteins are produced.

Roots are well nourished

NO3-

HCO3-

Soil Solution

Malate

K+

NO3-

Proteins

N.R.

K+

NO3-

After Ben-Asher and Pacardo, 1997

Normal metabolism at

non-saline conditions

in soil

A simplified model of chloride

accumulationPhotosynthesis

The K+ shuttle moves Cl- upwards

and malate downwards.

Protein production is halted

NO3-

HCO3-

Soil Solution

Malate

K+

NO3-

K+Cl-

Cl- Toxicity

Cl-

Cl- suppresses NO3- uptake

After Ben-Asher and Pacardo, 1997

in leaf-tips at

excessive Cl- in soil

The effect of Nitratein reducing

Cl- absorption

Antagonistic effect of Nitrate on chloride

in AVOCADO

Bar, Kafkafi & Lahav, 1987

Relieving chloride toxicity in avocado by increasing nitrate

concentration in irrigation water containing 16 mM Cl

Avocado, („Schmidt‟ Mex. salinity-sensitive) rootstock, Israel

Bar, Kafkafi & Lahav, 1987

0

0.5

1

1.5

2

2 4 10

Chloride in irrigation water (meq./L)

Nitrate combats chloride in irrigation water

2

8

16

Nitrate in irrigation

water (meq./L)Cl- in

leaves

(% of D.M)

Antagonistic effect of Nitrate on chloride

in AVOCADO

Lewis, Leidi & Lips, 1989

10

15

20

25

30

35

40

45

0 30 50 80

Nitrate- fed (4mM N)

Ammonium- fed (4mM N)

Plant shoot

fresh mass

(g)

Chloride in irrigation water (mM)

aa

b

a

aa

b

Antagonistic effect of Nitrate on chloride in MAIZE

b

a

The importance of K / Naratio in plant metabolism

Na’s toxicity stems from its competition with K

for enzymatic binding sites (60 of them, remember?)

High K / Na ratio in the plant

is more important than maintaining

low Na concentration

The importance of K / Na

The effect of

Potassium Nitrate

in increasing biomass production

under salinity conditions

30

80

130

180

230

280

0 2 4 6 8 10 12 14

2 mM8 mM14 mM

Potassium nitrate

Treatments

Ear

Yie

ld (

F.

W.g

/pla

nt)

E. C. of salinized nutrient solution (dS/m)

Double

yield

Imas & Feigin, 1995. Israel

Effect of salinity and Potassium Nitrate on

yield of Sweet Corn (cv. Jubilee)

0

100

200

300

400

500

To

tal

yie

ld (

g/p

lan

t)

*Montecarlo *Pearson

Control Salinized Salinized + Multi-K

Satti et Al. 1994

a

b

a

b

cc

Potassium Nitrate reverses the adverse effects of

salinity on Greenhouse TOMATOES

Potassium Nitrate increases fresh yield in greenhouse

CHINESE CABBAGE (cv. Kazumi) under salinity

780

860

940

1020

1100

1180

Fresh

Yie

ld (

g/p

lan

t)

0 0 1 5 10

Feigin et Al., 1990, Israel

a

a

b

ab

Data collected at 55 D.A.T

PN rate (mM)

EC= 1.8 EC= 5.0

EC= 6.0

EC= 5.5

EC= 6.5

ab

320

350

380

410

440

470

Fre

sh Y

ield

(g/p

lan

t)

0 0 1 5 10

Feigin et Al., 1990, Israel

a

c

a

b

ab

Data collected at 63 D.A.T

EC= 1.8 EC= 5.0 EC= 6.0EC= 5.5 EC= 6.5

PN rate (mM)

Potassium Nitrate increases salinity resistance in

greenhouse LETTUCE (cv. Salinas) under salinity

Under normal growing conditions

a modest application of Potassium Nitrate,

enables 10-35% higher harvested produce

from a given water quota

Under salinity conditions

a modest application of Potassium Nitrate

enables maintaining harvested produce

in spite of elevated EC values