INFLUENCE OF STORAGE AND SHELF-LIFE TIME ON ROTS OF PEACHES AND NECTARINES

In Italy, particularly in the Romagna area (South-East Po Valley), nectarines which ripen in the first three weeks of August are normally stored for 3-5 weeks in CA (1.5-1.8% O₂; 7- 8% CO₂; 0°C), while storage of peaches is fairly rare.
The main problem encountered is the high incidence of Monilinia laxa rot during post-storage distribution.
Our multi-annual trials have surveyed the influence of storage and shelf-life time on incidence of rots.
Regarding storage time (Table 1) the rot incidence was monitored on samples of 150 fruit (for each storage period) which were harvested at optimum ripeness, air precooled, stored at 0°C, and then after the storage periods held at 20°C for 3-5 days.
It emerged clearly that as the storage period is gradually prolonged, the incidence of rots also increases, although there is a great deal of difference from cultivar to cultivar.
With reference to the influence of shelf-life time at 22-25°C (Table 2) the incidence of rots was monitored daily (removing affected fruit to avoid nesting) for two consecutive years on 8 samples of 100 fruit from different packhouses in the Romagna area.
The fruit underwent the normal mechanical sizing and packaging operations.
It emerged that as post-storage shelf-life at 22-25°C is gradually extended, the incidence of rots increases; and also that all cultivars are susceptible to rots, though to a different extent.
In conclusion, the more storage times at 0°C and post-storage shelf-life at 22-25°C are prolonged, the greater the incidence of rots.

Table 1. Influence of storage (days) on rot incidence in peaches, nectarines and clingstone peaches.

Cultivar

Rots % (after storage plus 5 days at 20°C)

1

8

15

20

35

40

‘Rich Lady’ peach	15.3	15.0	25.1	47.6	90.6	/
‘Summer Lady’ peach	13.6	26.4	27.1	38.6	70.0	/
‘O’Henry’ peach	6.4	14.9	47.5	81.1	95.4	/
‘Maria Aurelia’ nectarine	2.3	6.7	/	21.8	48.8	64.5
‘Caldesi 2000’ nectarine	/	0.0	0.7	11.0	21.3	/
‘Sweet Red’ nectarine	/	1.8	4.3	11.9	16.3	/
‘Sweet Lady’ nectarine	/	4.8	6.3	9.6	11.3	/
‘Jungerman’ clingstone	/	51.7	/	71.2	85.4	93.6

Table 2. Rot incidence during shelf-life at 22–25°C (average of 2 annual trials in 8 packing houses)

Peaches

Rots at 22–25°C

Nectarines

% Rots at 22–25°C

	3 days		5 days		7 days		3 days		5 days		7 days
‘Spring Crest’	5.4		24.2		33.4	‘May Grand’	1.2		10.2		15
‘Springbelle’	12.9		34.2		37.6	‘Weinberger’	9.2		13.6		25.5
‘Flavor Crest’	1.75		13.9		20.7	‘Caldesi 2000’	3.6		8.8		15.9
‘Redhaven’	5.9		23.3		33.5	‘Spring Red’	3.5		10		21.3
‘Maria Bianca’	6.5		19.1		33.3	‘Independence’	2.9		10.9		26.5
‘Elegant Lady’	9.4		21.9		38.1	‘Stark Red Gold’	4.6		11.3		19.3
‘Suncrest’	8.2		21.4		38.1	‘Venus’	9.9		11.4		24.8
‘Fayette’	7.2		28.1		41.8	‘Caldesi 84’	4.8		8		19.8

Research supported by Finalized Project Fruit Culture, Italian Ministry of Agriculture and Forestry, Paper No.42

International Postharvest Science Conference Postharvest 96

G. Tonini, E. Tura

https://doi.org/10.17660/ActaHortic.1998.464.110