Harvest and cultivar effects on water vapour permeance in apples.
Maguire, K.; Banks, N.; Lang, S.;
Postharvest Horticulture Series - Department of Pomology, University of California Year: 1997 Issue: No. 16 Pages: 246-251 Ref: 17 ref.
1997
บทคัดย่อ
The large variation in estimates of skin water vapour permeance within populations of different horticultural crops masks treatment effects in experimental work and makes it difficult to develop strategies for controlling water loss. This study quantified contributions from various sources to total variation in estimates of water vapour permeance of Braeburn, Pacific Rose, Granny Smith and Cripps Pink apple fruits. Almost 30% of the total variation in water vapour permeance was associated with cultivar. The mean water vapour permeance for Braeburn fruits was 43.8 nmol s-1m-2Pa-1, for Pacific Rose 35.4 nmol s-1m-2Pa-1, for Granny Smith 17.3 nmol s-1m-2Pa-1 and for Cripps Pink 20.5 nmol s-1m-2Pa-1. Over 20% of the total variation was associated with harvest. This was the result of a large increase in water vapour permeance from 21.4 nmol s-1m-2Pa-1 at first harvest to 46.4 nmol s-1m-2Pa-1 at final harvest on average across all 4 cultivars. Fruit to fruit differences accounted for 25% of the total
variation in permeance values, indicating large fruit to fruit variation in water vapour permeance. An interaction effect of harvest and orchard explained >20% of the total variation, indicating that permeance of fruits from different cultivars increased by differing amounts with advancing harvest. Water vapour permeance in Pacific Rose and Braeburn increased substantially with later harvest but values for Granny Smith and Cripps Pink remained relatively constant. The data suggest that it may be worthwhile to implement more stringent measures to control weight loss in late harvested Braeburn and Pacific Rose fruits.