PrePre-Harvest Factors that
Affect Quality of Melons:
Calcium
SUMMARY
Overview General Information
UV Reflective Mulch
Fall 2003 Experience: Yuma
Jorge M. Fonseca
December 3, 2003
Calcium
UV Reflective Mulch
Western Vegetable Quality
MUSKMELON QUALITY
QUALITY AT HARVEST
Firms, well netted, well formed
USDA grade 1: 8% Sugar (10 Brix best)
~15 days shelf life at 36
- 41 oF.
4.4- 2.6 lbs
Strong orange for most muskmelon cv.
High levels of Vit. C and B carotene
QUALITY AT HARVEST
CALCIUM: BACKGROUND
Last two weeks are critical
Work of Gene Lester
Good leaf condition (no disease)
Four applications AA
- Cachelate or
Mannitol- Cacomplex
Good supply of Mg
No excessive irrigation or rainfall
Harvested at one- half to full slip
Honeydew: Fruit firmness increased,
same Brix
Cantaloupes: Same firmness and Brix.
Firmness was higher during storage
1
CALCIUM FACTOR
1st Study: Yuma-Fall 03
Essential in cell division and elongation
Fruit Growth!
Four applications after flowering
Primary building block for cell wall
Quality: At harvest, fresh cuts
Exchange balance of other nutrients
Gold
Express
Impac
Decrease permeability to Sodium
Effect of Calcium on Quality
Effect of Calcium Application on
Soluble Solids- - - Gold Express
Treatments
CaCl2: 0, 30, 60 mM
NaCl: 0, 50, 100 mM (solution)
Brix
13
o
(CaNo3)2: 0, 30,60 mM
14
12
11
10
9
1
Nutri-Cal
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18
CAN-17
Effect of Calcium Application on
Diameter and Resistance to
Penetration- -- cv. Gold Express
Effect of Calcium Application on
Yield--Gold Express
Yield---Gold
No differences*
140
Yield ( lbs)
130
120
110
100
90
80
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
2
Effect of Calcium Application on
Juice Leakage of Fresh Cuts, 5 d
after processing--Gold Express
processing---Gold
FUTURE WORK
Environment Effect
Ju i c e l e a k a g e ( m l / k g )
30
0% NaCl
25
Other Interactions:
20
Titanium
15
CAN 17
10
Humic Acid
5
0
1
2
Nutrical
3
4
5
6
7
8
9
CaCl 30
10
11
CaCl 60
12
13
14
15
CaNO3 30
UV REFLECTIVE MULCH
Effect of UV Reflective
Mulch on Number of Fruits
in Muskmelon Plants
No. Fruits / 10 plants
24
LSD = 0.998
22
16
17
CaNO3 60
18
More on Fresh Cuts and other melons
UV REFLECTIVE MULCH:
Effect on No. of Fruits
OTHER WORKS
Hymenopteran insects were found
more in reflective mulch (Pereira et
al., 2000).
20
Higher CO2 fixation (Ito et al., 1996)
18
16
Reflective
Control
100% increase in cantaloupe yield
(Stapleton and Summer, 2000).
3
UV REFLECTIVE MULCH
UV REFLECTIVE MULCH
The effect of Reflective Mulching on yield
The effect of Reflective Mulching on fruit
weight
LSD= 3.32
60
LSD= 0.15
50
Weight
(Lbs/10
plants)
2.8
2.7
40
2.6
30
Weight 2.5
(Lbs/fruit) 2.4
20
2.3
10
2.2
2.1
0
Mulch
Control
UV REFLECTIVE MULCH
Mulch
Control
FUTURE WORK
The effect of Jasmonic acid applied before
transplanting on early flowering
2.5
No. Flowers
after 9 d
transpl.
(in 10
plants)
2
Confirm 1st year results
Jasmonic
No-Jasmonic
1.5
Evaluate effect on shelf life
1
0.5
Evaluate water usage
0
Mulch
No-Mulch
Western Vegetable Quality
http://cals.arizona.edu/crops/vegetables/
WestVeg News: Electronic Newsletter
jfonseca@
jfonseca@ ag.arizona.edu
4