optimizing the capillary irrigation system for better yield and quality of hot pepper
Post on 06-Jan-2016
24 Views
Preview:
DESCRIPTION
TRANSCRIPT
V. Nalliah,R. Sri Ranjan Ph.D., P.Eng.
DEPT. OF BIOSYSTEMS ENGINEERING
UNIVERSITY OF MANITOBA
WINNIPEG
CANADA
CSBE/SCGAB 2008 50th Annual Conference
Vancouver, British ColumbiaJuly 13 - 16, 2008
Water conservation is important in irrigated agriculture limited water resources losses during irrigation competition for water among the different users
Improving the sustainability of water resources A potential solution is micro irrigation
frequent water application in small flow rates either on or below the soil surface
Drip, bubbler, spray jet, and subsurface irrigation systems
Types of irrigation in Canada 49.8% sprinkler irrigation
23.2% travelling gun
13.1% drip system and
13.8% other irrigation systems such as flooding and subsurface irrigation
Lower risk of evaporation, runoff losses from the soil surface
Greater savings of water, nutrient, and labor
Fewer chances for foliage diseases
More uniform plant growth
Very adaptable to different soil conditions
Gives a better chance to optimize the use of fertilizer and other chemical applications, and
lower rate of weed growth
Emitter
Plant pot
Water source
Schematic representation of the capillary irrigation system for container grown plants
H
•No pumping needed
•Low installation cost
•Undemanding operator expertise and system maintenance
Livingston (1908) introduced the negative pressure concept with porous clay cups
Richards and Loomis (1942) studied the performance of improved double-walled irrigator pots suitable for low flow rates and tension
Kato and Tejima (1982) performed a theoretical analysis in subsurface irrigation on the basis of different negative pressures
Lipiec et al. (1988) proposed a porous tube negative pressure water circulation technique suitable for measuring plant water uptake continuously under laboratory conditions
A study on the efficiency of subsurface irrigation under various elevation differences by Jiang et al. (2004) tested various pressures ranging from 0.5 m positive
pressure to 4.0 m negative pressure water infiltration into soil was observed up to 2.0 m soil
depth without applying any pressure to the system A soil-cooling and auto-irrigating system by Liu et
al. (2006) simultaneously irrigating and cooling the soil used porous ceramic pipes electric pump was used to maintain the pressure
To compare the yield and quality of hot pepper using capillary irrigation systems under different negative pressures.
To optimize the pressure of the system for producing pepper under controlled environment.
Perforated acrylic discs
PES
mem
bra
ne o
n
the d
isc
Plexiglass tube connected to the
cup
As growth progressed...
Initial setup
Jalapeno hot pepper (Capsicum annuum) was grown in a controlled-environment
-0.20, -0.40, -0.60 m negative pressure irrigation, and hand-watered treatments
A Completely Randomized Design (four treatments replicated seven times)
The four irrigation treatments received the same experimental conditions (light, temperature, RH)
Measurements taken were: Plant height, number of leaves, leaf area, water
consumption, and plant and fruit biomass
Hotness of pepper fruits was quantified using HPLC
Capsaicinoids are responsible for hotness of pepper
Capsaicinoids – Capsaicin & Dihydrocapsaicin The ground oven-dried fruits were used to extract the
capsaicinoid using acetonitrile by heating at 800C for 4h
An Agilent-1100 series HPLC system with 4.6x250 mm Eclipse XDB-C18 column was used
Standards of capsaicin and dihydrocapsaicin were used to identify and quantify the concentration of capsaicinoid in samples
PLANT HEIGHT LEAF NUMBER
LEAF AREA
Irrigation treatments
Irrigation water use
(kg)
Means and SE of the four treatments [a] Fresh shoot Dry shoot Fresh root Dry root WUE
(g) (g) (g) (g) (g/kg)Hand water 6.770 44.73a ±1.63 6.20ab ±0.19 2.18a ±0.17 1.50a ±0.19 1.14a ± 0.05-0.2 m pressure 4.437 45.16a±1.55 6.67a ±0.49 1.94a ±0.21 1.20ab ± 0.13 1.78b ± 0.14
-0.4 m pressure 2.335 32.51b ±1.73 5.39b ±0.22 1.41b ±0.18 0.98b ±0.11 2.73c ± 0.09
-0.6 m pressure 1.802 24.93c ±2.13 4.44b ±0.35 1.20b ±0.13 0.80b ±0.11 2.93c ± 0.30
Total water consumption, biomass yields, and WUE of hot pepper plant
[a] Means in the same column followed by different letters are significantly different using LSD at P < 0.05.
Irrigation treatments
Jalapeno hot pepper fruit biomass and size[a]
WUE Total
fresh fruit Total dry fruit
Fruit length
Fruit diameter
(g) (g) (mm) (mm) (g/kg)
Hand watering 42.48 a 3.69 a 44.5 a 18.9 a 6.27 b
-0.2 m pressure 41.40 a 3.59 a 44.3a 18.1 a 9.33 a
[a] Means followed by the same letter in the same column are not significantly different using LSD at P < 0.05.
Effect of two irrigation treatments on fruit biomass, fruit size, and water use efficiency (WUE)
Jalapeno hot pepper was able to grow well under capillary irrigation systems
Continuous water supply in the system eliminated the need for larger soil depth to store water
The plant height, leaf number, leaf area, and plant biomass were significantly higher in the -0.2 m and the control irrigation treatments compared to the -0.4 and -0.6 m treatments
The vegetative growth parameters were not statistically different between -0.2 m and the control irrigation treatments
The reproductive growth parameters (fruit length, diameter, and fruit biomass) in the -0.2 m capillary irrigation treatment were also comparable to the control treatment
The hotness of fruits in water starved plants were greater than in the plants under sufficient water
The -0.2 m negative pressure irrigation had better performance in terms of growth and yield parameters when compared to the manual irrigation while saving a considerable amount of water
The system is simple, inexpensive, water saving, and reproducible with minimum labor requirements for container grown plants
Manitoba Agri-Food Research & Development Initiative (ARDI)
Dr. Aluko Rotimi (Dept. of Human Ecology, University of Manitoba)
Ms. Amarbeer Bandari (Richardson Centre for Functional Foods and Nutraceuticals, University of Manitoba)
Dr. R. Zakaluk (Civil Engineering & Technology Department, Red River College, Winnipeg, Canada)
Questions?
top related