Reducing Postharvest Losses by using SO 2 Applications on Fresh Fig Cultivars Crisosto et al., Initial Fumigation Use of SO 2 Pad

Cultivars Brown Turkey Kadota (720 fruit) (884 fruit)

Measurements Fruit Quality (%) Sound fruit (commercial fruit) Fruit with decay Fruit with off-color Fruit with bleaching (‘Brown Turkey’)

Use of SO 2 to Control Decay

Luvisi, D.A. H.H. Shorey J.L. Smilanick, J.F. Thompson, B.H. Gump and J. Knutson Sulfur dioxide fumigation of table grapes. University of California, Division of Agriculture and Natural Resources Bulletin 1932, 21 pp.

Concentration x Time  At least 100 CT ppm per hour ppm per 30 min ppm per 15 min Smilanick, J.L.and D.J. Henson Minimum Gaseous Sulphur Dioxide Concentrations and Exposure Periods To Control Botrytis-Cinerea. Crop Protection. 11(6): Palou, L., C.H. Crisosto, D. Garner, L.M. Basinal, J.L. Smilanick and J.P. Zoffoli Minimum constant sulfur dioxide emission rates to control Gray Mold of cold-stored table grapes. Am. J. Enol. Vitic. 53(2):

Treatments 0 CT = 0 ppm-hr SO 2 CONTROL 25 CT = 25 ppm-hr SO 2 50 CT = 50 ppm-hr SO CT = 100 ppm-hr SO 2

Timer Dosimeter Meter

Effect of SO 2 CT on ‘Brown Turkey’ Bleaching Measured after 6 days at 32 o F CT25 CT50 CT100 CT % Bleaching

Measured after 6 days at 32  F +3 days at 68  F (shelf life) Y Sound = Commercial fruit. Effect of SO 2 CT on Sound Fruit (%) Treatment‘Brown Turkey’‘Kadota’ (CT) 0 CT CT CT CT

Effect of SO 2 on % Sound Fruit ‘Kadota’ after 6 days at 32 o F + Shelf Life (68 o F) Days at 68 o F % Sound Fruit 0 CT 25 CT 50 CT 100 CT

Effect of SO 2 on % Off-color Days at 68 o F % Fruit with OFF-COLOR 0 CT 25 CT ‘Kadota’ after 13 days at 32 o F + Shelf Life (68 o F)

Off-Color “Off-color” blemish in ‘Kadota’ fig

SO 2 Generating Pads One and two phases

Table Grape Export Packaging Box Liner Absorbent pad Fruit Diaper SO 2 pad

Investigating using SO 2 Pads with Fresh Fig Cultivars SO 2 Pad = w/ SO 2 generating pad during cold storage; removed during shelf life evaluation CONTROL = w/o SO 2 pad SO 2 pad

‘Kadota’ SO 2 pad no SO 2 pad Picture taken after 21 days at 32 o F

Conclusions SO 2 treatments look very promising (especially <50CT (ppm-hr). After cold storage and during first 2 days of shelf life, 25 CT displayed the highest % sound fruit. After a simulated postharvest handling, the SO 2 pad treatment displayed higher % sound fruit for both cultivars.

Acknowledgments Louise Ferguson, Plant Sciences, UC Davis Ed Stover, Plant Scienes, UC Davis Maxwell Norton, UCCE Merced Dan Rivers, UCCE Merced Richard Matoian, CA Fig Advisory Board Andrew Waterhouse, Enology, UC Davis Industry Cooperators Ron Radoicich, Terrestre Nursery Inc. Kevin Herman, Madera Co. Farm Advisor/Specialty Crop Javier Gil, Specialty Crop Doug Mueller, Specialty Crop Brent Holtz, Madera Co. Farm Advisor KAC Crisosto PH Research Staff Gayle Crisosto David Garner Vanessa Bremer Stephanie Dollahite Michael Pitchford Cooperators