vineyard water management - aggie horticulture...terroir and water management variety rootstock...

Vineyard Water Management

Pierre Helwi

Texas A&M AgriLife Extension Service

Grape CampNovember 7, 2016

Lady Bird Johnson Park Pioneer Pavilion, Fredericksburg, TX

Climate

Soil

Human factor

Genetic factor

Wine quality

Seguin 1986; Vaudour 2002; van Leeuwen et al., 2006

Terroir Concept

• Vineyard operations: water management…

• Winemaking

Temperature

Radiation

Precipitation

Climate

Composition and physical structure

Water-holding capacity

Pedoclimate

Nutrients

Soil Human factor

Viticulture practices- Irrigation- Floor management- …

Winemaking

Terroir and Water Management

Variety

Rootstock

Genetic factor

Soil evaporation

Vine transpiration

Vine Water Relations

Melotto et al., 2008


Water

Water vapor move out

Air (CO2) move in

OpenedStomata


Stomata open in sunlight for photosynthesis


Water


Stomata partially close in response to water stress reduction of

photosynthesis

ABA

ClosedStomata

Reduction in CO2 intake

Irrigation Management

1. When to start irrigation?

2. How much water to apply?

3. Should the irrigation strategy change during

the season?

Photo by Jeff Vanuga, USDA.

When to start irrigation?

Timing of irrigation determined by 3 techniques:

1. Physiological technique Visual symptoms


Photos by Michelle Moyer and Markus Keller, Washington State University

Grayish-green shoot tips Wilted leaves Curled and brown leaves Shriveled berries


2. Vine water status Pressure chamber (pressure bomb)

Stem water potential

Less than -1 MPa No stress

-1 to -1.2 MPa Mild stress

-1.2 to 1.4 MPa Moderate stress

-1.4 to -1.6 MPa High stress

Above -1.6 MPa Severe stress

Prichard et al. 2004Photos from UCCE Sonoma County

3. Soil water statusMoisture sensors

• Different types of sensors

• Critical values vary with sensor type

• Sensors determine if:

o Rainfall reaches root area

o Length of irrigation time

• Proper placement of sensors


Sensors

How much water to apply?


Evapotranspiration:

Loss of water from soil evaporation

and vine transpiration

Soil evaporation

Vine transpiration

Evapotranspiration = ET


ET0 calculated using:

• Air temperature

• Humidity

• Solar radiation

• Wind speed

Soil evaporation

Grass transpiration

Reference Evapotranspiration = ET0

http://texaset.tamu.edu/

http://texaset.tamu.edu/

Reference Evapotranspiration = ET0


Grapevine Evapotranspiration = ETc


ETcReference ET0 x Crop Coefficient (Kc) =

Kc increases during late-spring and early summer with canopy vigor

Crop Coefficient (Kc)


• For a particular vineyard block• At a specific time



KcPercentage shaded area

(PSA)x 0.017 =


Williams and Ayars 2005

PSA = Average width shaded area / Row width

Photos courtesy of Dr Ed Hellman




(PSA)x 0.017 =



Paso Panel




(PSA)x 0.017 =







KcPercentage shaded area(PSA)

x 0.017 =

Average width shaded area / Row width x 100

3 ft/ 10 ft x 100

= PSA

= 30%





KcPercentage shaded area(PSA)

x 0.017 =


Kc30% x 0.017 =

Kc0.51 =



ETcReference ET0 x Crop Coefficient (Kc) =

0.663 inches1.3 inches x 0.51 =

x 27,152gal/acre-inch

18,001 gal/acre

Replacing ALL water used by vine


Replacing PORTION of water used by vine

No deficit irrigation Deficit irrigation

Should the irrigation strategy change during the season?

Budbreak to bloom:

• Young bud hydration

• Shoot growth

• Canopy development

• Nutrient uptake from soil

Irrigation and Vine Developmental Stages

No deficit irrigation

Bloom to veraison:

• Canopy growth

• Cluster development

• Next season buds formation

• Cell division and expansion (berry size)


Deficit irrigation


Veraison to harvest:

• Excess water berry splitting and dilution of quality compounds

• Severe water stress high alcohol and astringency

Water deficit depending on strategy


A: Young vineyardB: Vineyard for aromatic whites

and fruity redsC: Vineyard for concentrated reds

Adapted from Ojeda et al. 2014


After harvest:

• Reserve for next season

• Signs of acclimation

• Root development

No deficit irrigation

Floor management

Water management by floor management

Cover crops:

• reduction of excessive vine vigor

Vigorous vines Balanced vinesPhotos courtesy of Dr Ed Hellman


Cover crops:

• adapted to high rainfall regions

Low rainfallHigh rainfall



Cover crops:

• Several options:

o Type of cover crops

o Cover crop width

o Mowing height and timingCover crop width

Alternate row cultivationMowing height and timing

Ph

oto

s cou

rtesy of D

rEd

Hellm

an


Cover crops:

• To be avoided in new planted vineyards


Grape Irrigation Decision Guide

What time of year is it?

Budbreak to bloom Bloom to veraison Veraison to harvest Harvest to dormant

Sufficient rainfall to replenish 100% of vine water loss?

Yes

No need to irrigation

No

Water to replace full ET

How severe are signs?

Signs of water stress?

SevereMild

Continue with current strategy. Adapt it with

conditionsIncrease irrigation

rates

YesNo

Want to practice deficit irrigation?

Yes No

Continue with current strategy

Slowly reduce irrigation rates

NoYes


Vigorous canopy?

NoYes

Reduce irrigation rates


NoYes

Rainfall or sufficient irrigation?

No need to irrigate

Irrigation

Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards



Budbreak to bloom


Yes


No





Budbreak to bloom Bloom to veraison


Yes


No




SevereMild



rates

YesNo


Yes No






Budbreak to bloom Bloom to veraison Veraison to harvest


Yes


No




SevereMild



rates

YesNo


Yes No



NoYes


Vigorous canopy?

NoYes






Budbreak to bloom Bloom to veraison Veraison to harvest Harvest to dormant


Yes


No




SevereMild



rates

YesNo


Yes No



NoYes


Vigorous canopy?

NoYes



NoYes

Rainfall or sufficient irrigation?

No need to irrigate

Irrigation


Conclusion

• Irrigation + floor management to manage soil moisture

• Understanding of vine environment

• There are no silver bullets!

• Grapevines are tolerant to water stress

THANK YOUFOR YOUR ATTENTION !

More literatures

• Burt 2012, Wine Grape Irrigation Management

• Hellman, Irrigation Scheduling of Grapevines with Evapotranspiration Data

• Washington State University Extension, Irrigation basics for eastern Washington vineyards

• Peters, Practical use of soil moisture sensors for irrigation scheduling

• Prichard et al. 2004, Deficit irrigation of quality winegrapes using micro-irrigation techniques

• Prichard, Winegrape irrigation scheduling using deficit irrigation techniques

• Westover and Beal 2014, Using Soil Moisture Sensors for Vineyard Irrigation Management

vineyard water management - aggie horticulture...terroir and water management variety rootstock...

Documents