STEMEND SPLITTING OF APPLE FRUIT

1
STEM-END SPLITTING OF APPLE FRUIT

• Peggy Collier
• Deirdre Fahy
• Preston Andrews
• Robert Evans

2
RESEARCH HIGHLIGHTS

• Calcium sprays reduced splitting
• Most SES not associated with IRC
• Structurally SES due to
• Cell orientation
• Cell wall weakness
• Stem bowl more mature than equator
• SES simulation with razor nick test

3
CALCIUM SPRAY

• Imperial Gala/Mark trees
• Fruit ripe
• Calcium chloride (8 lbs/100 gal)
• Rainfall 2 days after spray
• Counts 6 days after spray

Split
1998
4
VANTAGE TREATMENTS

• Royal Gala/M.26 trees
• Non-replicated, grower applied treatments
• Alternate tree removal
• Packhard (2.5 gal/season) with Ca sprays
• Reduced irrigation
• Packinghouse records

Splitting
1997
5
STRUCTURAL VIEWPOINTS
TANGENTIAL
RADIAL
Bowl
Equator
6
ETHYLENE
Bowl / equator
Imperial Gala
Mean
Fruit No.
7
1999 OBJECTIVES

• 1. Anatomical comparison of Gala with
  non-splitting variety
• 2. Reduce maturity in stem bowl
• 3. Mechanical assay to quantify splitting
  potential ? wedge razor nick tests
• 4. Relationship between localized water, nutrient
  carbohydrate status

8
ACKNOWLEDGMENTS

• Funding from
• WTFRC
• Abbott Laboratories
• WSU
• Cooperators
• Auvil Fruit Company
• Doyle Tye Fleming

9
TANGENTIAL
RADIAL
Bowl
Equator