Issue link: https://read.dmtmag.com/i/622402
6 JANUARY 15, 2016 Good Fruit Grower www.goodfruit.com A Washington State University horticulture researcher has found a new use for a familiar compound. Spraying pear trees with glycinebetain (GB) four weeks prior to picking allowed farmers to leave fruit on trees longer and to significantly improve its firmness when it came out of storage. Dr. Amit Dhingra, a WSU horticulture department associate professor, had growers in Washington's Wenatchee Valley spray their pear trees with a com- pound normally used to control cracking in sweet cher- ries. Marketed as Bluestim, Greenstim and Verdera, it is an osmoregulator, used to control moisture loss in crops. "What it really does," Dhingra said, "is prevent the degradation of chlorophyll." Dhingra's quest began one day while he was standing in a Cashmere Valley orchard having a conversation with a grower. The grower asked if there was a way to keep pears greener. After giving the question some thought, he remem- bered working with GB earlier in his career. Initially, he was unaware of its labeled use; after he found out, how- ever, he quickly secured a patent for WSU for pre- and postharvest applications. Dhingra's growers sprayed the compound onto trees at 2.5, 5 and 10 pounds per acre two weeks prior to har- vest. Testing for fruit pressure and firmness at harvest, they saw no difference between treated and untreated d'Anjou and Bartlett pears. Improved freshness But when he and his team opened the controlled-at- mosphere (CA) storage rooms in January, they were con- fronted with "an amazing difference." Untreated pears showed a 34 percent decrease in firmness while treated pears showed only a 4 percent decrease. "In effect," he said, "ripening occurred under suspended animation. But when the fruit came out, it woke up." Firmer peARs 16 lbs 20 lbs 12 lbs 8 lbs 4 lbs Fruit pressure AUG SEP OCT NOV DEC JAN FEB Application August 17 Harvest september 20 CA room open JANuArY 7 Regular storage FebruArY 18 treAted* uNtreAted Firmness Compound improves *d'Anjou pears treated with glycinebetain (gb) at 10 pounds per acre source: WAshiNgtoN stAte uNiversitY A study found that d'Anjou pears sprayed with glycinebetain (GB) treated pears was initially lower on release from storage, it rose Once removed from storage, the treated pears were greener and firmer than the controls. The Brix level was 8° but rose to 12° within two weeks. The added firmness translates to longer shelf life, he says. Based on fruit pressure, he estimated it can be extended by at least two weeks. GB delivers other attributes consumers will find attrac- tive, too. One is good color after storage. "We noticed blush in a lot of the control fruit, and this product showed it can help in eliminating it," Dhingra said. "This may be useful for Granny Smith and Golden Delicious apples." David Sugar, now a retired Oregon State University- Medford fruit researcher, discovered another attribute. More research ahead for compound to improve pear firmness. by David Weinstock Postharvest For any questions please visit our website at hostetlerfarms.com or call us at (317) 539-4067. The knip-boom process takes time, so orders must be placed 2 years in advance. J F M A M J J A S O N D J F M A M J J A S O N D