Improving Drip Fumigation for Strawberry Production in California

Transcription

1 Improving Drip Fumigation for Strawberry Production in California Ruijun Qin, Oleg Daugovish, Suduan Gao, James Gerik, Tom Gordon, Husein Ajwa & Brad Hanson

2 Major issues on drip fumigation practice High emissions occur in PE tarped field Air quality issues. Field trial in Oxnard 2006: Drip fumigation (1,3-D & CP) at lbs/ac Inline (61% 1,3-D, 33% CP).

3 Major issues on drip fumigation practice High emissions occur in PE tarped field Air quality issues. Unsatisfactory pest control. Increasing number of pathogen-infested fields. Difficulty in controlling pests at bed-center or shoulder, especially at deeper depth. Weed problem.

4 New plastic films Low permeability film (LPF): Virtually Impermeable Film (VIF) Totally Impermeable Film (TIF) VIF TIF Field trial in Oxnard 2009

5 Proposed solutions Low permeability film (LPF) covering: Increasing drip line number: Traditional way PE film with 2 drip lines New strategies LPF with 4 drip lines

6 2013 Camarillo Trial Bed configuration: 45 (width), 16 (height). Traditional drip-line depths: 2. Parallel 4 dripping line (2 deep) Two shallow (2 ) plus 2 deep (7 ) dripping lines. Fumigant rate: full rate vs. half rate. Film type: PE vs LPF. Soil type: sandy loam Oxnard Trial 2015 Oxnard Trial

7 Installing drip tapes: 2 outer drip tapes for fumigation 4 parallel drip tapes 2 shallow + 2 deep drip tapes

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9 Results Fumigant emissions Fumigant distribution Pest control Strawberry production

10 Emissions from tarped beds (2015 Oxnard trial) TIF tarping << PE tarping. Drip tape layout did not impact emission. Tri-Clor Fumigant 200 lbs/ac

11 Emissions from tarped beds (2014 Oxnard trial) VIF tarping << PE tarping. Drip tape layout did not impact emission. Tri-Clor Fumigant 224 lbs/ac

12 Emissions from TIF tarped bed (2013 Camarillo trial) Deep-application had much less emission than shallow-application. High emission from TIF was due to flaw during manufacture. Pic-Clor 60 EC (a mixture of 57% CP, 37% 1,3-D) Full rate: 300 lbs/ac

13 Emissions from uncovered furrow Trace level regardless of treatments: Long distance from drip tape to furrow Soil compaction at furrow Mostly covered by extended film

14 Results Fumigant emissions Fumigant distribution Pest control Strawberry production

15 Fumigant distribution in soil profile In soil profile Bed center: 4 18 Bed edge: 4 18 Concentration-time index (CT) ( g cm -3 h) - An indicator for pest control result. - Higher CT means better pest control.

16 Critical CT value of chloropicrin for pest control Weeds/Pathogens/Nematodes CT ( g cm -3 h) Knotweed (Polygonum arenastrum) 74 Chickweed (Stellaria media) 208 Purslane (Portulaca oleracea) 208 Little Mallow (Malva parviflora) Redstem Filaree (Erodium cicutarium) Pythium ultimum 6 NA NA Verticillium dahliae 348 Phytophthora cactorum 142 Fusarium oxysporum 142 Citrus nematode (Tylenchulus semipenetrans Cobb) 10 Rootknot nematode (Meloidogyne spp. Chitwood) 10 * The values for weeds and pathogens were calculated based on the data in Klose et al. (2007) with the fumigants as the mixture of 1,3-D and CP. The values for nematode was cited from Schneider et al. (2008) with the fumigant as CP. Schneider et al., HORTSCIENCE 43: ; Klose et al., Crop Protection 26:

17 0 2L/full/TIF 0 4L/full/TIF CT in 2015 Oxnard trial with Tri-Clor EC: full rate: 200 lbs/ac half rate: 100 lbs/ac Soil depth (cm) Soil depth (cm) Bed width (cm) 2L/full/PE Soil depth (cm) Soil depth (cm) Bed width (cm) 4L/half/TIF Bed width (cm) Bed width (cm)

18 0 4L/full/VIF 0 2L/full/VIF CT value of 2014 Oxnard trial with Tri-Clor EC Full rate: 224 lbs/ac Soil depth (cm) Bed width (cm) Bed width (cm) 0 2L/full/PE 0 4L/half/VIF 0 2L/half/VIF Soil depth (cm) CT value is accumulated (fumigant concentration * fumigation time) Bed width (cm) Bed width (cm) Bed width (cm)

19 0 CT value of CP in TIF/deep/full 0 CT value of CP in TIF/deep/half CT value of 2013 Camarillo trial with Pic-Clor 60 EC (a mixture of 57% CP, 37% 1,3-D) Full rate: 300 lbs/ac Soil depth (cm) CT value of CP in TIF/shallow/full Soil depth (cm) CT value for CP in TIF/shallow/half Soil depth (cm) Bed width (cm) Soil depth (cm) Bed width (cm)

20 Results Fumigant emissions Fumigant distribution Pest control Strawberry production

21 Four drip tapes: Fusarium survivorship (2015 trial) two shallow (2.5 ) + two deep (7 ) 6 depth Spores per gram of soil 12 depth Not detectable Location in bed

22 Fusarium survivorship (2015 trial)

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24 Pest control (2014 Oxnard trial) Pre-buried nutsedge tubers. The occurrence of weeds at the holes where strawberry plants grow.

25 Pathogen disease occurred in control plots (2014 Oxnard trial)

26 Pest control in TIF treatments (2013 trial) Pre-buried Fusarium oxysporum: Detected in non-fumigated beds, especially at the bed-center. All the fumigation treatments provided 100% control, both at bed-center or near bed edge. Pythium ox. in soil (near bed edge from 0-30 cm: Detected in non-fumigated beds. All fumigation treatments provided 100% control.

27 Results Fumigant emissions Fumigant distribution Pest control Strawberry production

28 Marketable fruit yield: Jan-April 2015 trial

29 Strawberry yield (2014 Oxnard trial) VIF treatments showed a better yield during early season (December March). * The measurement was on 20 plants per beds.

30 Strawberry yield (2013 Camarillo trial) Marketable berry yields during early season were generally no difference. * The measurement was on 20 plants per beds.

31 Summary on drip fumigation studies LPF covering and deep application can reduce fumigant emissions from tarped beds dramatically. Emission from furrow was not a concern in raised-beds systems. Higher emissions and poor pest control occurs in PE covered beds. Increasing drip line numbers, deep application, and LPF covering will be the optimized fumigation technology in raised-bed systems.

32 Acknowledgment Grant from the California Department of Food and Agriculture Specialty Crop Block Grant Program and from the Walmart Foundation and administered by the University of Arkansas System Division of Agriculture Center for Agricultural and Rural Sustainability. Cooperating growers, Steve Imoto, Glen Imoto, Henry Ito, and their field crew providing the tested field, field equipment, and field preparation. Crop Production Service (CPS), TriCal, Inc. provided fumigation service. Technical assistance was provided by Water Management Research Unit, USDA-ARS, Parlier, CA and the Department of Plant Sciences, UC Davis.

33 Ruijun (Ray) QIN University of California-Davis/ USDA-ARS 9611 S. Riverbend Ave., Parlier, CA Tel: Cell: