Economic Impacts of Termination Timing for Irrigation and Plant Bug Control

Juan Monge* Diana M. Danforth* Tina Gray Teague**

Mark J. Cochran* J. L. Lund**

T. J. Sangepogudavid**

*Department of Agricultural Economics and Agribusiness, University of Arkansas, Fayetteville

**Department of Entomology, University of Arkansas at Arkansas State University

Introduction

Problem Statement

Circumstances Pest pressure: Bugs – 535,326 cotton bales Constant draught: Worst in 20 years Rising energy prices Achieve appropriate earliness

Consequences Frequent irrigation and insecticide application Higher production costs

Objectives

Determining if longer periods of irrigation and insecticide control reward producers through: Higher yields Fiber attribute values Profits

Establishing economically profitable termination guidelines based on crop maturity

Data Sources and

Methods

Experimental Design

Yield and fiber quality data Three-year experiment at U of A Lon Mann

Cotton Research Station Designed as a split plot

Main plot: Irrigation termination (5 levels) Rainfall in 2005 and 2006

Sub plot: Insect control termination (4 levels)

Experimental Design

2004 2005 2006

Irrigation 14-Jul NAWF = 7.2 NAWF = 7.1 1 wk prior to flowering22-Jul NAWF = 5.6 NAWF = 5 NAWF = 7.330-Jul NAWF = 5+100 DD60s NAWF = 5+300 DD60s NAWF = 518-Aug NAWF = 5+360 DD60s NAWF = 5+166 DD60s31-Aug NAWF = 5+580 DD60s NAWF = 5+650 DD60s

Insecticide 16-Jul NAWF=7.2 NAWF=8.6 1 wk prior to flowering21-Jul NAWF=5.6 NAWF=7.1 NAWF = 7.38-Aug NAWF=5+240 DD60s NAWF=5+95 DD60s NAWF = 5+280 DD60s24-Aug NAWF=5+450 DD60s NAWF=5+413 DD60s NAWF = 5+650 DD60s

TreatmentDate of final application

Crop maturity status at final application

Experimental Design

Nodes Above White Flower (NAWF) Monitored using COTMAN

HVI fiber quality determinations International Textile Center at Texas Tech

University More technical information:

Teague et al. (2005) Danforth et al. (2006)

Lint Values

Market adjust the price of cotton 2004, 2005 and 2006 CCC loan schedules Micronaire, color/leaf grade, fiber length,

uniformity and strength Base loan rate:

52.00 cents per pound

Irrigation and insecticide costs

Irrigation costs Furrow irrigation $7.96 per acre per application

Insecticide costs Applied with a 60-foot John Deer Hi-Boy

$1.04 per acre Insecticide prices are constant

Irrigation and insecticide costs

Irrigation NAWF = 7.2 7.96NAWF = 5.6 15.92NAWF = 5+100 DD60s 31.84NAWF = 5+360 DD60s 55.72NAWF = 5+580 DD60s 71.64

Insecticide NAWF=7.2 37.19NAWF=5.6 85.88NAWF=5+240 DD60s 140.84NAWF=5+450 DD60s 171.16

Irrigation NAWF = 7.1 39.80NAWF = 5 55.72NAWF = 5+300 DD60s 71.64

Insecticide NAWF=8.6 15.53NAWF=7.1 36.45NAWF=5+95 DD60s 48.71NAWF=5+413 DD60s 54.87

Irrigation 1 wk prior to flowering 39.80NAWF = 7.3 47.76NAWF = 5 55.72NAWF = 5+166 DD60s 63.68NAWF = 5+650 DD60s 87.56

Insecticide 1 wk prior to flowering 5.58NAWF = 7.3 6.44NAWF = 5+280 DD60s 11.17NAWF = 5+650 DD60s 14.57

2005

2006

Treatment Crop maturity status at final application

2004

Cost per treatment ($/acre)

Statistical analysis

Variables analyzed using ANOVA for the different irrigation and insect control treatments Yields (lbs/acre) Lint values ($/lb) Profits ($/acre)

Mean separation – Fisher’s Least Significant Difference

Results

2004 experiment

TreatmentDate of final application

Crop maturity status at final application

Yields (lbs/acre)*Lint values

($/lb)*Profits ($/acre)*

Irrigation 14-Jul NAWF = 7.2 1,357.77 a 0.47 516.77 a

22-Jul NAWF = 5.6 1,353.56 a 0.46 481.55 b

30-Jul NAWF = 5+100 DD60s 1,437.60 a 0.46 522.02 a

18-Aug NAWF = 5+360 DD60s 1,642.79 b 0.48 627.64 c

31-Aug NAWF = 5+580 DD60s 1,679.44 b 0.46 597.21 d

LSD05 = 121.31 p>0.05 LSD05 = 25.80

Insecticide 16-Jul NAWF = 7.2 1,388.26 a 0.45 b 532.04

21-Jul NAWF = 5.6 1,391.34 a 0.45 b 506.56

8-Aug NAWF = 5+240 DD60s 1,561.65 b 0.48 a 577.87

24-Aug NAWF = 5+450 DD60s 1,635.68 b 0.48 a 583.06LSD05 = 153.78 LSD05 = 0.02 p>0.05

* Amounts with different letters are significantly different at the 5% significance level.

Yields, lint values and profits for each irrigation main plot and insecticide termination sub-plot effect in 2004 trial

Irrigation termination 2004

600

800

1,000

1,200

1,400

1,600

1,800

2,000

NAWF = 7.2 NAWF = 5.6 NAWF = 5+100DD60s

NAWF = 5+360DD60s

NAWF = 5+580DD60s

2004 crop maturity at final irrigation application

Yie

ld (

lbs/

ac)

150

250

350

450

550

650

Pro

fit

($/a

c)

Yield (lbs/ac)

Profits ($/ac)

Insect control termination 2004

600

800

1,000

1,200

1,400

1,600

1,800

2,000

NAWF=7.2 NAWF=5.6 NAWF=5+240DD60s

NAWF=5+450DD60s

2004 crop maturity at final insecticide application

Yie

ld (

lbs/

ac)

150

250

350

450

550

650

Pro

fit

($/a

c)

Yield (lbs/ac)

Profit ($/acre)

2005 experiment

TreatmentDate of final application

Crop maturity status at final application

Yields (lbs/acre)*Lint values

($/lb)*Profits ($/acre)*

Irrigation 14-Jul NAWF = 7.1 1,582.28 0.53 754.8322-Jul NAWF = 5 1,591.58 0.55 779.7830-Jul NAWF = 5+300 DD60s 1,691.93 0.55 814.80

Insecticide 16-Jul NAWF = 8.6 1,599.01 0.54 787.5621-Jul NAWF = 7.1 1,586.01 0.55 772.158-Aug NAWF = 5+95 DD60s 1,663.68 0.54 799.1424-Aug NAWF = 5+413 DD60s 1,639.03 0.54 773.69

* No significant differences were observed.

Yields, lint values and profits for each irrigation main plot and insecticide termination sub-plot effect in 2005 trial

2006 experiment

TreatmentDate of final application

Crop maturity status at final application

Irrigation 14-Jul 1 week prior to flowering 865.96 a 0.45 a 333.82 a

22-Jul NAWF = 7.3 944.01 ab 0.47 a 377.60 ab

30-Jul NAWF = 5 1,103.71 b 0.48 a 451.72 b

18-Aug NAWF = 5+166 DD60s 1,307.57 c 0.52 b 594.79 c

31-Aug NAWF = 5+650 DD60s 1,452.58 c 0.54 b 674.70 c

Insecticide 16-Jul 1 week prior to flowering 1,035.53 a 439.48 a

21-Jul NAWF = 7.3 1,042.62 a 442.12 a

8-Aug NAWF = 5+280 DD60s 1,238.71 b 542.25 b

24-Aug NAWF = 5+650 DD60s 1,222.19 b 522.24 b

* Amounts with different letters are significantly different at the 5% significance level.

Yields, lint values and profits for each irrigation main plot and insecticide termination sub-plot effect in 2006 trial

Profits ($/acre)*Lint values

($/lb)*Yields (lbs/acre)*

LSD05 = 105.21

LSD05 = 59.66

LSD05 = 0.03

p>0.05

LSD05 = 189.87

LSD05 = 116.13

0.48

0.48

0.50

0.50

Irrigation termination 2006

600

800

1,000

1,200

1,400

1,600

1,800

2,000

1 w k prior toflow ering

NAWF = 7.3 NAWF = 5 NAWF = 5+166DD60s

NAWF = 5+650DD60s

2006 crop maturity at final irrigation application*

Yie

ld (

lbs/

ac)

150

250

350

450

550

650

Pro

fit

($/a

c)

Yield (lbs/ac)

Profits ($/ac)

*Termination at NAWF=5 + 166 DD60s is equivalent to NAWF=5 + 366 DD60s because of rainfall.

Insect control termination 2006

600

800

1,000

1,200

1,400

1,600

1,800

2,000

1 w k prior toflow ering

NAWF = 7.3 NAWF = 5+280DD60s

NAWF = 5+650DD60s

2006 crop maturity at final insecticide application

Yie

ld (

lbs/

ac)

150

250

350

450

550

650

Pro

fit

($/a

c)

Yield (lbs/ac)

Profits ($/ac)

Conclusions

Problem Statement

Insect control termination NAWF = 5 + 280 DD60s Yield and profits did not increase beyond 280 DD60s COTMAN guideline (350 DD60s) can economically be

applied to tarnished plant bug

Irrigation termination NAWF = 5 + 360 DD60s Yield and profits did not increase beyond 360 DD60s Irrigation termination based on COTMAN monitoring

is feasible

Acknowledgments

Questions