Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for...

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Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department of Crop and Soil Sciences North Carolina State University M.S. McGinnis North Carolina Department of Agriculture & Consumer Services-Agronomic Division 2017_AP19_Vann.pdf AP2017 - Document not peer-reviewed by CORESTA

Transcript of Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for...

Page 1: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Organic Fertilizer Programs for

Tobacco Seedling Production

M.C. Vann, L.R. Fisher, & R.W. Seagroves

Department of Crop and Soil Sciences

North Carolina State University

M.S. McGinnis

North Carolina Department of Agriculture & Consumer Services-Agronomic Division

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Page 2: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Presentation Outline

• Organic Seedling Production

• Production Concerns

• Methods & Materials

• Results & Discussion

• Conclusions

• Questions

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Page 3: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Organic Seedling Production

• Production occurs in a float system

– Nutrients are added directly to the water

– OMRI listed soilless media sources

• Common Nutrient Sources:

– Allganic Sodium Nitrate (16-0-0 or 15-0-2)

– Peruvian Seabird Guano

– Bat Guano

– Allganic Potassium Sulfate (0-0-52)

– Acetic acid for bicarbonate adjustments

– Micronutrient sources vary depending upon need

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Page 4: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Organic Seedling Production Concerns

• Variable N composition of nutrient sources

– Sodium Nitrate: 0% Urea, 0% NH4+, 100% NO3

-

– Seabird Guano: 69% Urea, 30% NH4+, 0.65% NO3

-

– 16-5-16: 0% Urea, 37.5% NH4+, 62.5% NO3

-

• Variable rate of N mineralization

– Aerobic vs. Anaerobic conditions • (field vs. float bed)

• Difficult to dissolve guano in solution

• High bicarbonate concentration – ≥2.0 meq HCO3

-/L (>200 mg/L) can stunt seedlings (2,4)

• High P concentration – “leggy”/“spindly” seedling characteristics (3)

• High Na concentration – <70 mg Na/L is recommended (4)

• High Urea and NH4+ concentration (5)

– Excessive NO2- is toxic to seedlings

– Low microbial populations for oxidation in media

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Page 5: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Objectives

1. Identify organic fertilizer programs best suited for seedling

production

2. Identify potential concerns associated with those programs

3. Further develop Extension recommendations

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Page 6: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Methods & Materials

Treatment List

1. Guano

2. Guano + Gypsum

3. Sodium Nitrate

4. Sodium Nitrate + Gypsum

5. Guano + Sodium Nitrate

6. Guano + Sodium Nitrate + Gypsum

7. 16-5-16 (conventional control)

Experimental Design

• Central Crops Research Station

– June-July 2016

– November 2016-January 2017

• RCBD, 3 replications per evaluation

• 6 trays per bed

– 100 designated cells/tray for data collection

– 12.7 cm float water depth

– Fertilizer added 9 and 21 DAS

• Variety: K326 (Rickard Seed Co.)

• Media: Carolina Choice All Natural Mix

• Data analyzed using PROC Mixed in SAS

ver. 9.4

• Figures created using Sigma Plot ver. 12

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Page 7: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Table 1. Organic fertilizer programs evaluated and the respective targeted nutritional content.

Fertilizer Programa,b,c Total N P2O5 K2O Ca

__________________________________________________mg L-1__________________________________________________

Guano 125 115 20 (SG) + 105 (0-0-52) --

Guano + Gypsum 125 115 20 (SG) + 105 (0-0-52) 50

Sodium Nitrate 125 0 125 (0-0-52) --

Sodium Nitrate + Gypsum 125 0 125 (0-0-52) 50

Guano + Sodium Nitrate 44 (SG) + 81 (SN) 40 7 (SG) + 118 (0-0-52) --

Guano + Sodium Nitrate + Gypsum 44 (SG) + 81 (SN) 40 7 (SG) + 118 (0-0-52) 50

16-5-16 125 40 125 --

a Guano (SG), Sunleaves 12-11-2 Peruvian Seabird Guano; Sodium Nitrate (SN), SQM Allganic 16-0-0; 16-5-16, SQM Ultrasol Premium; 0-0-52, SQM Allganic Potassium Sulfate b Fertilizer program applied twice per season, 9 and 21 days after seeding c Nutrient content calculated based upon manufacturers reported analysis

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Page 8: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Data Collection

• Dissolved Oxygen: – YSI DO Meter

– 5 day intervals prior to solution collection and water addition

• Solution Samples: – Source Water

– 5 day intervals

– 474 mL solution volume

– After beds filled to 12.7 cm depth

– Samples analyzed by NCDA&CS

• Media Samples: – 20 DAS and at conclusion of study

– 10 cells/tray/treatment • N=60/treatment/replication

– Samples analyzed by NCDA&CS

• Seedling Measurements: – Total plants, usable plants, stem

height, & stem diameter

– Conclusion of study

– 10 cells/tray/treatment • N=60/treatment/replication

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Page 10: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Table 2. Nutrient concentration, pH, and bicarbonate concentration of source water and soilless media

prior to seedinga. Measurements are expressed in mg L-1 unless otherwise noted.

Nutrient Environment One Environment Two

Solution Media Solution Media

Total Nmin 3.96 9.03 4.12 45.68

NH4+-N 0.55 3.30 0.51 1.20

NO3--N 3.41 5.73 3.61 44.50

Urea-N 0.54 0.25 0.16 0.00

P 0.09 0.13 0.09 0.10

K 1.92 23.35 2.11 74.73

Ca 3.50 60.93 4.11 88.98

pH 6.12 4.52 6.21 4.37

HCO3- (meq L-1) 0.30 -- 0.38 --

a Soilless media and source water solution samples analyzed by the North Carolina Department of Agriculture and Consumer Services-Agronomic Division, Raleigh, NC

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Page 11: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

5 10 15 20 25 30 35 40 45

DO

Con

cen

trati

on

(m

g D

O L

-1)

0

1

2

3

4

5

6

7

Guano

Guano + Gypsum

Sodium Nitrate

Sodium Nitrate + Gypsum

Guano + Sodium Nitrate

Guano + Sodium Nitrate + Gypsum

16-5-16

5 10 15 20 25 30 35 40 45 50 55 60 65

0

1

2

3

4

5

6

7

Days After Seeding

Environment One Environment Two

Figure 1. Dissolved oxygen (DO) concentration in float water solution as influenced by

seedling fertility program. Data are presented for each growing environment.

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5 10 15 20 25 30 35 40 45 50 55 60 65

0

25

50

75

100

125

150

175

200

225

250Guano

Guano + Gypsum

Sodium Nitrate

Sodium Nitrate + Gypsum

Guano + Sodium Nitrate

Guano + Sodium Nitrate + Gypsum

16-5-16

5 10 15 20 25 30 35 40 45

Am

mon

ium

-N C

on

cen

trati

on

(m

g N

H4

+ L

-1)

0

25

50

75

100

125

150

175

200

225

250

Days After Seeding

Environment One Environment Two

Figure 2. Ammonium-nitrogen concentration in float water solution as influenced by seedling

fertility program. Data are presented for each growing environment.

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Page 13: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

5 10 15 20 25 30 35 40 45

Nit

rate

-N C

on

cen

trati

on

(N

O3

- L-1

)

0

25

50

75

100

125

150

175

200

225

250Guano

Guano + Gypsum

Sodium Nitrate

Sodium Nitrate + Gypsum

Guano + Sodium Nitrate

Guano + Sodium Nitrate + Gypsum

16-5-16

5 10 15 20 25 30 35 40 45 50 55 60 65

0

25

50

75

100

125

150

175

200

225

250

Days After Seeding

Environment One Environment Two

Figure 3. Nitrate-nitrogen concentration in float water solution as influenced by seedling

fertility program. Data are presented for each growing environment.

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5 10 15 20 25 30 35 40 45

pH

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

Guano

Guano + Gypsum

Sodium Nitrate

Sodium Nitrate + Gypsum

Guano + Sodium Nitrate

Guano + Sodium Nitrate + Gypsum

16-5-16

Days After Seeding

Environment One Environment Two

Figure 4. Float water solution pH as influenced by seedling fertility program. Data are

presented for each growing environment.

5 10 15 20 25 30 35 40 45 50 55 60 65

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

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5 10 15 20 25 30 35 40 45

Bic

arb

on

ate

Con

cen

trati

on

(m

eq H

CO

3

- L-1

)

0

2

4

6

8

10

12

14

16Guano

Guano + Gypsum

Sodium Nitrate

Sodium Nitrate + Gypsum

Guano + Sodium Nitrate

Guano + Sodium Nitrate + Gypsum

16-5-16

5 10 15 20 25 30 35 40 45 50 55 60 65

0

2

4

6

8

10

12

14

16

Days After Seeding

Environment One Environment Two

Figure 5. Bicarbonate concentration in float water solution as influenced by seedling fertility

program. Data are presented for each growing environment. Dashed line represents 2.0 meq

threshold.

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5 10 15 20 25 30 35 40 45

NH

4

+ o

r N

O3

- Con

cen

trati

on

(m

g L

-1)

0

50

100

150

200

250

pH

6.0

6.5

7.0

7.5

8.0

NH4

+-N

NO3

--N

pH

Days After Seeding

Figure 6. Ammonium, nitrate, and float water pH as influenced by guano application. Data are

presented for each growing environment.

5 10 15 20 25 30 35 40 45 50 55 60 65

NH

4

+ o

r N

O3

- Concentr

ati

on (

mg L

-1)

0

50

100

150

200

250

pH

6.0

6.5

7.0

7.5

8.0 2017

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Page 17: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Additional Solution Observations

• Urea-N concentration:

– Guano > Guano + Sodium Nitrate > Sodium Nitrate ≥ 16-5-16

– Maximum of 20-25 mg/L, decreased over time

• P concentration:

– Guano > 16-5-16 > Guano + Sodium Nitrate > Sodium Nitrate

– Maximum of 40-50 mg/L in Guano only treatment

– <1.0 mg/L observed in Sodium Nitrate only treatment

• Na concentration:

– Sodium Nitrate > Guano + Sodium Nitrate > Guano > 16-5-16

– >350 mg/L observed in Sodium Nitrate only treatment

– High Na did not impact seedling growth, Coggins (4) did not observe injury at 580 mg/L

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Page 18: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Soilless Media Nutrition

• Similar trends to nutrient concentration in float water solution

– Guano based treatments had highest NH4+ concentration

– High NO3- concentration where sodium nitrate was exclusive N source

– NO3- concentration increased from the 20 DAS sampling to the conclusion of the study

• NH4+ concentration decreased

– Low P (<1.0 mg/kg) concentration when Sodium Nitrate was the only N source

• Soluble salts (SS) concentration highest when Sodium Nitrate was included in

fertility program.

– SS injury was not observed in either environment

– Delayed and split fertilizer application was likely beneficial

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Page 19: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Table 3. Total transplants, usable transplants, transplant height, and transplant diameter reported by corresponding treatment as affected by

fertility programsa,b.

Treatment Listc Total Plants Usable Plants Stem Diameter Stem Height

---------------%--------------- mm plant-1 cm plant-1

Guano 90 a 78 c 2.76 b 5.62 b

Guano + Gypsum 91 a 79 bc 2.84 b 6.08 ab

Sodium Nitrate -- -- -- --

Sodium Nitrate + Gypsum -- -- -- --

Guano + Sodium Nitrate 91 a 85 ab 3.48 a 6.27 ab

Guano + Sodium Nitrate + Gypsum 93 a 86 a 3.43 a 6.47 ab

16-5-16 88 a 79 bc 3.30 a 6.62 a aTreatment means followed by the same letter within the same column are not significant at the α=0.05 level. Data are pooled across two environments.

bTreatments comprised of Sodium Nitrate only removed from analysis

c Guano, Sunleaves 12-11-2 Peruvian Seabird Guano; Sodium Nitrate, SQM Allganic 16-0-0; 16-5-16, SQM Ultrasol Premium

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16-5-16

SG + 0-0-52

16-0-0 + 0-0-52

SG + 16-0-0 + 0-0-52

16-0-0 + 0-0-52 + Gypsum SG+ 0-0-52 + Gypsum

SG + 16-0-0 + 0-0-52 + Gypsum

SG, Seabird Guano

16-0-0, Sodium Nitrate

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Page 21: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Guano + 16-0-0 + 0-0-52

16-5-16 Guano + 0-0-52 + Gypsum

Guano + 0-0-52

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Page 22: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Conclusions • 5 of 7 treatments produced acceptable transplants

– Treatments absent of P did not produce usable transplants (Sodium Nitrate only)

– Supplemental P is required, not enough in source water or media

• Organic “blend” treatment was best treatment. – Guano + Sodium Nitrate + 0-0-52 (+ Gypsum)

– Produced highest number of usable transplants

– Balanced ammonium:nitrate ratio (1:2 or 1:3)

– HCO3- concentration is more favorable for seedling growth

• Identified Guano as a source of HCO3-

– Delayed/split fertilizer application may reduce HCO3- stunting

– Low media pH buffers against significant pH increase from HCO3-

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Page 23: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Grower Recommendations

Fertilizer Programs

• Program One:

• Seabird Guano (13.9 oz./100 gal) – 104 g 12-11-2/100 L H2O

• 0-0-52 (2.7-3.2 oz./100 gal) – 20-24 g/100 L H2O

• Program Two:

• Seabird Guano (4.9 oz/100 gal) – 37 g 12-11-2/100 L H2O

• Sodium Nitrate (6.8 oz/100 gal) – 51 g 16-0-0/100 L H2O

• 0-0-52 (3.0 oz/100 gal) – 20-24 g/100 L H2O

Considerations

• Reduce guano particle size

• Soak guano in hot water for 24 hours

• Fertilize in split applications

– 9 and 21 DAS

• Target 125 mg N/L

• Target 40 mg P/L

• Target 125 mg K/L

• Apply Ca, Mg, S, and B as needed

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Page 24: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

References

1. USDA-NASS. 2016. Certified Organic Survey-2015 Summary. Accessed September 25,

2017. http://usda.mannlib.cornell.edu/usda/nass/OrganicProduction//2010s/2016/

OrganicProduction-09-15-2016.pdf

2. NCDA&CS. 2013. Solution Analysis for Tobacco Transplant Float Beds. Accessed

September 25, 2017. http://www.ncagr.gov/agronomi/pdffiles/floatbed.pdf

3. Fisher, LR and MC Vann. 2017. Producing Healthy Transplants in a Float System. In: LR

Fisher, editor, 2017 North Carolina State University Flue-Cured Tobacco Production Guide

(AG-187 (Revised)). Raleigh, NC: North Carolina Cooperative Extension Service. p. 44-57.

4. Coggins, TE. 1993. Effect of Sodium and Bicarbonate on Tobacco Seedling Production in

the Greenhouse Float System [thesis]. Raleigh, NC: North Carolina State University. p. 129.

5. Pearce, RC, Y Zhan, and MS Coyne. 1998. Nitrogen Transformations in the Tobacco Float

System. Tobacco Science 42(4):82-88.

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Page 25: Organic Fertilizer Programs for Tobacco Seedling Production€¦ · Organic Fertilizer Programs for Tobacco Seedling Production M.C. Vann, L.R. Fisher, & R.W. Seagroves Department

Acknowledgements

• Technical Assistance

– Rick Seagroves

– Scott Whitley

– Hunter Mason

– Michelle McGinnis

– NCDA&CS

• Material Donation

– SQM

– Carolina Soil Company

– Rickard Seed Company

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Questions??

Matthew C. Vann: [email protected]

Website: tobacco.ces.ncsu.edu

North Carolina Tobacco Information

@NCSUtobacco

@ncsu_tobacco

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