Good to Know: A gem of a pear

US 71655-014 has been tested in Hood River, Oregon, for ten years, and is expected to be released soon.

A 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, 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 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 russet 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.
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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 respectively 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 could easily be managed in plantings at twice the density, thus roughly doubling our trial yields. Return bloom and production in the following year were not significantly reduced by crop load.

Delayed harvest

In 2011, we examined the effects of delayed harvest timing on fruit size and quality, both at harvest and following extended cold storage. Fruit were harvested on four dates at weekly intervals from a high-density, trellised hedgerow planting with 906 trees per acre. The initial harvest occurred when fruit reached 12 pounds flesh firmness, which was previously determined to coincide with maximum storability. Fruit were stored in regular-atmosphere storage at 30°F and evaluated at monthly intervals for seven months. Fruit quality attributes (fruit firmness, soluble solids, total acids, extractable juice, and fruit weight) were assessed upon removal from cold storage and after seven days of ripening at room temperature.

Fruit weight increased from 205 grams (box size 100) at the first harvest to 242 grams (box size 80) at the fourth harvest. Fruit firmness decreased from 12.2 to 9.9 pounds over the three-week harvest period, but fruit of each harvest timing maintained good firmness throughout the six-month storage period. Sugars remained at 13 percent irrespective of harvest timing, and storage duration. Total acids declined in storage by roughly half, increasing the sugar-to-acid ratio. Fruit retained exceptional eating quality through six months of storage, but lost ripening capacity beyond six months. Internal breakdown was observed at the seven-month evaluation in the delayed harvested fruit.

Fruit size was markedly improved by both thinning and harvest delay, without compromising fruit quality. This pear has considerable versatility, satisfying consumers who prefer crisp, juicy pears, as well as those who prefer pears ripened to a softer texture. The five-year average full bloom date for 014 is 1.3 days before Bartlett flowering in Hood River, and it appears to be cross-compatible with d’Anjou and Bartlett.

We will establish a 0.6-acre plot of 014 in Hood River in 2014. The high-density planting will serve as a demonstration orchard for growers, horticulturists, and packers to visit, and will provide a volume of fruit for test marketing and sale.