Vineyard Water Management

Transcription

1 Vineyard Water Management Pierre Helwi Texas A&M AgriLife Extension Service Grape Camp November 7, 2016 Lady Bird Johnson Park Pioneer Pavilion, Fredericksburg, TX

2 Terroir Concept Climate Human factor Vineyard operations: water management Winemaking Wine quality Soil Genetic factor Seguin 1986; Vaudour 2002; van Leeuwen et al., 2006

3 Terroir and Water Management Climate Temperature Radiation Precipitation Genetic factor Variety Rootstock Soil Composition and physical structure Water-holding capacity Pedoclimate Nutrients Human factor Viticulture practices - Irrigation - Floor management - Winemaking

4 Vine Water Relations Vine transpiration Soil evaporation Melotto et al., 2008

5 Vine Water Relations Air (CO 2 ) move in Water vapor move out Water Stomata open in sunlight for photosynthesis Opened Stomata Melotto et al., 2008

6 Vine Water Relations Reduction in CO 2 intake Water ABA Closed Stomata Stomata partially close in response to water stress reduction of photosynthesis Melotto et al., 2008

7 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.

8 When to start irrigation?

9 When to start irrigation? Timing of irrigation determined by 3 techniques: 1. Physiological technique Visual symptoms Grayish-green shoot tips Wilted leaves Curled and brown leaves Shriveled berries Photos by Michelle Moyer and Markus Keller, Washington State University

10 When to start irrigation? 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 Photos from UCCE Sonoma County

11 When to start irrigation? 3. Soil water status Moisture sensors 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

12 How much water to apply?

13 How much water to apply? Evapotranspiration = ET Vine transpiration Soil evaporation Evapotranspiration: Loss of water from soil evaporation and vine transpiration

14 How much water to apply? Reference Evapotranspiration = ET 0 Grass transpiration Soil evaporation ET 0 calculated using: Air temperature Humidity Solar radiation Wind speed

15 How much water to apply? Reference Evapotranspiration = ET 0

16 How much water to apply? Grapevine Evapotranspiration = ET c Reference ET 0 x Crop Coefficient (K c ) = ET c K c increases during late-spring and early summer with canopy vigor

17 How much water to apply? Crop Coefficient (K c ) For a particular vineyard block At a specific time

18 How much water to apply? Crop Coefficient (K c ) For a particular vineyard block At a specific time Percentage shaded area (PSA) x = K c PSA = Average width shaded area / Row width Williams and Ayars 2005 Photos courtesy of Dr Ed Hellman

19 How much water to apply? Crop Coefficient (K c ) For a particular vineyard block At a specific time Percentage shaded area (PSA) x = K c PSA = Average width shaded area / Row width Paso Panel

20 How much water to apply? Crop Coefficient (K c ) For a particular vineyard block At a specific time Percentage shaded area (PSA) x = K c PSA = Average width shaded area / Row width Williams and Ayars 2005 Photos courtesy of Dr Ed Hellman

21 How much water to apply? Crop Coefficient (K c ) Percentage shaded area (PSA) x = K c Average width shaded area / Row width x 100 = PSA 3 ft / 10 ft x 100 = 30% Williams and Ayars 2005 Photos courtesy of Dr Ed Hellman

22 How much water to apply? Crop Coefficient (K c ) Percentage shaded area (PSA) x = K c 30% x = K c 0.51 = K c Williams and Ayars 2005

23 How much water to apply? Grapevine Evapotranspiration = ET c Reference ET 0 x Crop Coefficient (K c ) = ET c 1.3 inches x 0.51 = inches x 27,152 gal/acre-inch 18,001 gal/acre

24 How much water to apply? Grapevine Evapotranspiration = ET c

25 How much water to apply? Replacing ALL water used by vine Replacing PORTION of water used by vine No deficit irrigation Deficit irrigation

26 Should the irrigation strategy change during the season?

27 Irrigation and Vine Developmental Stages Budbreak to bloom: Young bud hydration Shoot growth Canopy development Nutrient uptake from soil No deficit irrigation

28 Irrigation and Vine Developmental Stages Bloom to veraison: Canopy growth Cluster development Next season buds formation Cell division and expansion (berry size) Deficit irrigation

29 Irrigation and Vine Developmental Stages Veraison to harvest: Excess water berry splitting and dilution of quality compounds Severe water stress high alcohol and astringency Water deficit depending on strategy

30 Irrigation and Vine Developmental Stages A: Young vineyard B: Vineyard for aromatic whites and fruity reds C: Vineyard for concentrated reds Adapted from Ojeda et al. 2014

31 Irrigation and Vine Developmental Stages After harvest: Reserve for next season Signs of acclimation Root development No deficit irrigation

32 Floor management

33 Water management by floor management Cover crops: reduction of excessive vine vigor Vigorous vines Balanced vines Photos courtesy of Dr Ed Hellman

34 Water management by floor management Cover crops: adapted to high rainfall regions High rainfall Low rainfall Photos courtesy of Dr Ed Hellman

35 Water management by floor management Cover crops: Several options: o Type of cover crops o Cover crop width o Mowing height and timing Cover crop width Mowing height and timing Alternate row cultivation Photos courtesy of Dr Ed Hellman

36 Water management by floor management Cover crops: To be avoided in new planted vineyards Photos courtesy of Dr Ed Hellman

37 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 Signs of water stress? No Mild Yes How severe are signs? Severe Signs of water stress? Yes No Vigorous canopy? Rainfall or sufficient irrigation? Yes No need to irrigate No Irrigation Yes Slowly reduce irrigation rates Want to practice deficit irrigation? No Continue with current strategy Continue with current strategy. Adapt it with conditions Increase irrigation rates Yes Reduce irrigation rates No Slowly reduce irrigation rates Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards

38 Grape Irrigation Decision Guide What time of year is it? Budbreak to bloom Sufficient rainfall to replenish 100% of vine water loss? Yes No No need to irrigation Water to replace full ET Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards

39 Grape Irrigation Decision Guide What time of year is it? Budbreak to bloom Sufficient rainfall to replenish 100% of vine water loss? Yes No Bloom to veraison Signs of water stress? No Yes No need to irrigation Water to replace full ET Mild How severe are signs? Severe Yes Want to practice deficit irrigation? No Continue with current strategy. Adapt it with conditions Increase irrigation rates Slowly reduce irrigation rates Continue with current strategy Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards

40 Grape Irrigation Decision Guide What time of year is it? Budbreak to bloom Bloom to veraison Veraison to harvest Sufficient rainfall to replenish 100% of vine water loss? Yes No Signs of water stress? No Yes Signs of water stress? Yes No No need to irrigation Water to replace full ET How severe are signs? Vigorous canopy? Mild Severe Yes Slowly reduce irrigation rates Want to practice deficit irrigation? No Continue with current strategy Continue with current strategy. Adapt it with conditions Increase irrigation rates Yes Reduce irrigation rates No Slowly reduce irrigation rates Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards

41 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 Signs of water stress? No Mild Yes How severe are signs? Severe Signs of water stress? Yes No Vigorous canopy? Rainfall or sufficient irrigation? Yes No need to irrigate No Irrigation Yes Slowly reduce irrigation rates Want to practice deficit irrigation? No Continue with current strategy Continue with current strategy. Adapt it with conditions Increase irrigation rates Yes Reduce irrigation rates No Slowly reduce irrigation rates Adapted from Washington State University Extension, Irrigation basics for eastern Washington vineyards

42 Conclusion Irrigation + floor management to manage soil moisture Understanding of vine environment There are no silver bullets! Grapevines are tolerant to water stress

43 THANK YOU FOR YOUR ATTENTION!

44 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