Embed Size (px)
DESCRIPTION
Nathan Howell's research project in collaboration with the University of Kentucky and Western Kentucky University on the potential of saving thousands of gallons of water per acre with the same effects as the current standard recommendations.
Citation preview
The Effects of Drip Irrigation Methods on Plasticulture
Tomato Yield and Quality in South-Central Kentucky
-
Disabilities accommodated with prior notification
Educational programs of the Kentucky Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability, or national origin.
Dr. Tim Coolong – University of Kentucky Department of HorticultureDr. Martin Stone – Western Kentucky University Department of Agriculture
Role of Water in Tomato Production
Production Cost - 1/3
Limited natural resource
‘How Much to Apply’? Just enough to be productive Not a drop extra
General Guidelines exist but dependent on Local conditions Seasonal variation
Experimental Details
Conducted at WKU farm
Bowling Green, Ky.
Summer 2010 -2011
Plasticulture• Black• Drip irrigation• Fertigation• Staked
‘Mountain Fresh Plus’
Experimental Design
Randomized Complete Block
4 replications
4 treatments
Statistical Analysis – SAS p < 0.05 Means separated by Duncan’s MRT if sig. F test
Treatments
ID 36 – University of Kentucky Recommendation
Acre Inch per Week
½ ID 36
Water Balance Method Pan Evaporation at Nolin Lake Dam, ACOE Crop Coefficient, Source: Tekinel and Çevik (1993) Computed Water needs Weekly =
• Water Balance Method
How Much to Apply?
UK recommendation for tomatoes ID 36 Extension Publication
• May overestimate water demands
• Original source of information unknown
Farmers apply 1 acre inch water/week Standard crop recommendation Based on ‘Farmer Knowledge’
Water Balance Method
Most efficient method based on Stage of crop growth
• Transplant vs. fruiting Environmental conditions
• Drives demand for water
Water Balance Method
Pan Evaporation Data Affect plant Transpiration Temperature, humidity, solar radiation and wind
Crop Coefficient Crop specific Model of Water use through crop growth stages Based on actual data
Determine weekly tomato water usage
Crop Coefficient Model
Tekinel and Çevik (1993)
Actual Crop Coefficients and Pan Evaporation
1 3 5 7 911 13
0
0.5
1
weekly pan
Weeks After Transplanting
Hypothesis
Standard recommendations overestimate water needs of tomatoes Over/under estimate needs through season
Reduction of water usage will not reduce yield and quality
Water Manipulation
Checked measured by water meters on each treatment
Metered by gallon
Three treatments were altered weekly for water supply ID 36 ½ ID 36 Water Balance Method
Confirmation by meters and
tensiometers
1 2 3 4 5 6 7 8 9 10 11 12 13 14
0
100
200
300
400
500
Weekly Water Distribution
ID 36
Acre Inch Week
1/2 ID 36
Water Balance
Weeks after Transplanting
Gal
lons over
over
under
100%
71%
54%
73%
Cumulative Water Usage
ID 36
Acre Inch Week
1/2 ID 36
Water Balance
Weeks After Transplanting
Tensiometers
Detect soil water potential related to soil water content “dummy root” Used to confirm accuracy of water applied
• Readings 0–10: Saturated soil• Readings 70 and higher: Stress range
Each treatment Opposite drip irrigation lines ½ way between plants 30 cm deep
Read weekly
19-M
ay
28-M
ay
6-Ju
n
15-Ju
n
24-Ju
n
3-Ju
l
12-Ju
l
21-Ju
l
30-Ju
l
8-Aug
17-A
ug
0
10
20
30
40
50
60
70
80
90
ID 36Acre-Inch Wk1/2 ID 36Water Balance
Weeks After Transplanting
Soil
Wat
er T
ensi
on (c
entib
ars)
WEEKLY TENSIOMETER READINGS
Wetter
Stress Range
Harvest
Weekly for 7 weeks - (7/12)
‘Breaker’ stage = harvest
Sorted by USDA grades Quality
• Marketable – Unmarketable (Cull) Size
• Small, medium, large, extra large Weighed - (lbs) Noted radial cracks
Table 1. The effects of four irrigation treatments on marketable yield and yields of small, medium, large, and extra-large fruit as well as percent of culls of Mt. Fresh Plus tomatoes grown in Bowling Green, Ky., in 2010. Treatments are ordered based on marketable yield (highest to lowest).1
Conclusion
Based upon one years data
we can produce as many quality marketable tomatoes with less irrigation ½ the high recommended volume irrigation significantly influences yield data suggest that water distribution may play just as important role as volume
• Ex: Treatments of Acre Inch Week and Water Balance Method
over
over
under
