Good Fruit Grower

September 2012

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GOOD TO KNOW A research report from Todd Einhorn, Steve Castagnoli, Janet Turner, and Richard Bell Pears A gem of a pear It can be eaten at harvest, like an Asian pear, but then ripens and softens after harvest. known as US 71655-014, has been extensively tested at Oregon State University's Mid- Columbia Agricultural Research and Extension Center in Hood River over the past ten years and may be of interest to pear growers looking for new varieties to plant. The USDA has filed an application for a joint cultivar release with Oregon State University, Michigan State University, and Clemson University. A decision is expected soon. The proposed name is Gem, though the pear cannot be referred to by its name until the official release. The selection, known as 014 for short, came from a cross of Sheldon and selection A US 62563-004. It is a European pear but can be consumed fresh at harvest. It has a crisp, juicy texture and sweet, but mild flavor more similar to an Asian pear than a European pear. Following cold storage and ripening at room temperature, however, the fruit softens to about three pounds firmness and develops typical pear flavors, though it is not a melting, dessert-type pear. It has a five- to six-month storage life under regular atmosphere storage. In OSU's field and lab tests, 014 has demonstrated several appealing attributes including: • early fruiting (precocity) • consistent high annual production • attractive fruit appearance • good storability • good consumer acceptance The selection has a red blush over a green background, and fruit finish has been rus- set free over several seasons of testing in Hood River. Following six months of regular- atmosphere storage, fruit remain scald free and maintain good internal quality. This pear has consistently high fruit set and, compared with d'Anjou, has significantly earlier yields and higher cumulative production. One potential drawback observed from initial testing is that 014 tends to have small fruit, weighing about 150 grams (135 fruit per 44-pound box). However, in these trials, 014 was unthinned. We, therefore, have examined two strategies to improve fruit size of 014: crop-load management and harvest timing. Table 1 Effect of crop load Effects of crop load on production and average fruit size of the new pear variety US 71655-014. Treatment Yield Projected yield Average Average fruit size crop load Heavy Moderate Light Commercial Figure 1 Distribution of US 71655-014 fruit size when thinned to four crop load levels. 10 15 20 25 30 35 40 45 0 5 FRUIT SIZE SOURCE: Todd Einhorn www.goodfruit.com Heavy crop Moderate crop Light crop Commercial (lb/tree) 120 88 54 65 (bins/acre) 40 29 18 22 fruit size (g) 150 170 208 203 (no. per 44-lb box) 135 120 100 100 "If you want to keep up with the Jones' stay close to Dave Wilson Nursery. We have experienced quality, honesty and integrity as a family tradition at Dave Wilson Nursery." - David Jackson & Family, Family Tree Farms Dave Wilson Nursery Hickman office (209) 874-1821 Reedley office (559) 638-6675 www.davewilson.com GOOD FRUIT GROWER SEPTEMBER 2012 25 new fireblight-resistant, European pear selection bred by Dr. Richard Bell at the U.S. Department of Agriculture's Appalachian Fruit Research Station in Kearneysville, West Virginia, is expected to be released soon. The selection, Crop load A two-year crop-load study was initiated on sixth-leaf trees trained to a central leader and budded to the Old Home x Farmingdale 97 rootstock. Fruit was thinned at 50 days after full bloom to four crop- load levels based on the number of fruit per square centimeter of trunk cross-sectional area: Level 1: 8-10 fruit per cm2 Level 2: 6-8 fruit per cm2 Level 3: 2-4 fruit per cm2 Level 4: Simulating commercially thinned Bartlett (3-5 fruit per cm2 after thinning) Fruit of 014 fruit mature five to ten days after Bartlett in Hood River. Average fruit weight at harvest was 150, 171, 208, and 203 grams respec- tively for levels 1 through 4, equivalent to box sizes 135, 120, 100, and 100. In addition to the marked improvement in average fruit weight, overall fruit-size distribution of the two heaviest thinned treatments was significantly improved. The projected yield for the sixth-leaf trees ranged from 30 to 15 bins per acre, going from the highest to lowest crop loads. The trees were planted at a density of 282 trees per acre, but canopy volume and trunk size of Level-3 and Level-4 trees indicated that they US 71655-014 has been tested in Hood River, Oregon, for ten years, and is expected to be released soon. PERCENT 70 80 90 100 110 120 135 Smaller than 135 n 135 Photo by Steve CaStagnoli

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