`Shenandoah': A New Fire Blight-resistant Pear Cultivar

`Shenandoah' is a new European pear (Pyrus communis L.) cultivar which combines resistance to fire blight with fruit of excellent quality. The original seedling tree was selected in 1985 from a cross of `Max Red Bartlett'× US 56112-146, and was tested under the original seedling number, US 78304-057. The fruit of `Shenandoah' is pyriform in shape, and moderately large in size, averaging 72 mm in diameter and 92 mm in height. Skin color at harvest is light green, turning yellow-green when ripe. The skin finish is glossy, and 10% to 20% of the fruit surface is blushed red. There is light tan russet at the calyx. Lenticles are slightly conspicuous, and are surrounded by small, light brown russet. The stem is medium to long (≈25 mm), of medium thickness, and slightly curved. Harvest maturity occurs about four weeks after `Bartlett', and the fruit will store in refrigerated (-1 °C) air storage for at least four months without core breakdown or superficial scald. The flesh texture is moderately fine, juicy, and buttery. Grit cells are moderately small and occur primarily around the core and in a thin layer under the skin. The flavor is aromatic, similar to `Bartlett', and is moderately acidic during the first two months of storage, becoming subacid after longer storage. The tree is moderate in vigor on `Bartlett' seedling and `OHxF 97' rootstocks, and upright-spreading in habit. Shenandoah' blooms in mid-season, similar to `Bartlett'. Yield has been moderately high and precocious, and with no pronounced biennial pattern. Fire blight resistance is similar to `Seckel', with infections extending no further than 1-year-old branches. Artificial blossom inoculations indicate a moderate degree of blossom resistance to fire blight infection.

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060 `Blake's Pride' Fire Blight-resistant Pear Cultivar

HortScience ◽

10.21273/hortsci.34.3.451d ◽

1999 ◽

Vol 34 (3) ◽

pp. 451D-451

Author(s):

Richard L. Bell ◽

T. van der Zwet ◽

R.C. Blake

Keyword(s):

Thin Layer ◽

Fire Blight ◽

Agricultural Research ◽

Moderate Degree ◽

The Core ◽

Infection Resistance ◽

Agricultural Research And Development ◽

Harvest Maturity ◽

Development Center ◽

Fruit Surface

`Blake's Pride' has been released jointly by USDA and The Ohio State Univ. as a new fire blight-resistant cultivar. The original seedling tree was selected in 1977 at the Ohio Agricultural Research and Development Center in Wooster by R.C. Blake and T. van der Zwet from a cross of US 446 × US 505, performed in 1965 by H.J. Brooks, and was tested under the original seedling number, OHUS 66131-021. The fruit of `Blake's Pride' is pyriform to round-pyriform in shape, and is moderate in size, averaging ≈2.75″ to 3″ in diameter, and 3.25″ in height. The stem is short, medium in thickness, and upright. Skin undercolor is yellow, the finish is glossy, and 20% to 30% of the fruit surface is covered with a smooth, light tan russet. Harvest maturity occurs about 3 weeks after `Bartlett', and the fruit will store in air storage for at least 3 months without core breakdown or superficial scald. The flesh texture is moderately fine, juicy, and buttery. Grit cells are moderately small and occur primarily around the core and in a thin layer under the skin, similar to `Bartlett'. The flavor is subacid and aromatic. The tree is moderate in vigor on `Bartlett' seedling rootstock, and upright-spreading in habit. Yield has been moderate to moderately high. Fire blight infections are rare, and extend no further than 1-year-old growth. Artificial blossom inoculations indicate a moderate degree of resistance of blossoms to fire blight infection. Resistance of `Blake's Pride' to both shoot and blossom infection is much greater than that of `Bartlett'.

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515 PB 447 `POTOMAC': A NEW FIRE BLIGHT-RESISTANT PEAR CULTIVAR

HortScience ◽

10.21273/hortsci.29.5.505c ◽

1994 ◽

Vol 29 (5) ◽

pp. 505c-505

Author(s):

Richard L. Bell ◽

T. van der Zwet ◽

C.K. Chandler ◽

J.C. Scheerens

Keyword(s):

Thin Layer ◽

Skin Color ◽

Fire Blight ◽

Blight Resistance ◽

Pear Cultivar ◽

Commercial Trial ◽

High Level ◽

Harvest Maturity ◽

High Degree ◽

Light Green

`Potomac' has been released as a new pear cultivar which combines a high level of resistance to fire blight with excellent fruit quality. Selected from a cross of `Moonglow' × `Beurre d'Anjou', it was tested under the seedling number, US 62537-048. Fruit are ovate-pyriform in shape, and average 73mm in diameter. Skin color is light green and the finish is glossy at harvest maturity, which occurs about 2 weeks after `Bartlett'. Flesh texture is moderately fine, buttery, and juicy; grit cells are small and limited to a thin layer under the skin. Flavor is subacid, with mild aroma, and similar in character to `Beurre d'Anjou'. Fruit may be ripened after harvest without cold storage, but `Potomac' is more susceptible to superficial scald than Beurre d'Anjou if stored for more than eight weeks. The tree is moderately vigorous. Yield and precocity are moderate. Fire blight resistance is greater than that of `Seckel', with a high degree of resistance in both shoots and blossoms. The cultivar is recommended for home orchards and limited commercial trial.

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BREEDING OF NEW PEAR WINTER CULTIVAR 'PANDORA'

Romanian journal of Horticulture ◽

10.51258/rjh.2020.06 ◽

2020 ◽

Vol 1 (1) ◽

pp. 45-50

Author(s):

Nicolae Braniște ◽

Madalina Militaru

Keyword(s):

Fruit Quality ◽

Skin Color ◽

Fire Blight ◽

Blight Resistance ◽

Color Changes ◽

Biennial Bearing ◽

Pear Psylla ◽

Fruit Growing ◽

Good Potential ◽

Yellowish White

Psylla and fire blight resistance combined with fruit quality are still pearbreeding aims at Research Institute for Fruit Growing (RIFG) Pitești, Romania. The new pear cultivar 'Pandora' was registered in 2019, being released by interspecific hybridization between 'Euras' cv. [(PyrusserotinaxOlivier de Serres) x Doyenne d'hiver] and 'Tse Li' cv. (P.ussuriensis). The trees are medium vigor, weak branching and semi-upright habit being productive and with low tendency to biennial bearing. The fruit ripens 10-15 days earlier than 'Euras', at end of September.Fruit weight is about 250g, flesh is yellowish white, fine, crisp, juicy, sweetand flavored. The skin color changes from green to yellow upon maturity. It is highly resistant to fire blight and pear psylla under the standard spraying program. Therefore, this new cultivar shows a good potential for commercial fruit growing.

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Late Harvest and Delayed Cooling Induce Internal Browning of `Ya Li' and `Seuri' Chinese Pears

HortScience ◽

10.21273/hortsci.29.6.667 ◽

1994 ◽

Vol 29 (6) ◽

pp. 667-670 ◽

Cited By ~ 18

Author(s):

Carlos H. Crisosto ◽

David Garner ◽

Gayle M. Crisosto ◽

Steve Sibbett ◽

Kevin R. Day

Keyword(s):

Skin Color ◽

Harvest Date ◽

Full Bloom ◽

The Core ◽

Date Fruit ◽

Brown Discoloration ◽

Subsequent Storage ◽

Internal Browning ◽

Light Green ◽

Storage Temperatures

Brown discoloration of the core, carpels, and flesh areas of `Ya Li' and `Seuri' Chinese pears [Pyrus bretschmeideri (Rehd.)] depended on harvest date. Fruit harvested no later than 180 days after full bloom (3000 degree days) did not develop the disorder. Browning of the core and flesh tissues increased when cooling was delayed, but was not influenced by subsequent storage temperatures of 0,10, or 20C. In both cultivars, the onset of internal browning was evident after storage in fruit that had been harvested when skin color had changed from green to light green-yellow. Thus, skin color can be used to determine harvest date to avoid internal browninincidence during storage of `Ya Li' and `Seuri' Chinese pears.

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Evaluation of pear (Pyrus communis L.) hybrid combinations for the transmission of fire blight resistance and fruit characteristics

Czech Journal of Genetics and Plant Breeding ◽

10.17221/17/2017-cjgpb ◽

2018 ◽

Vol 54 (No. 2) ◽

pp. 78-85 ◽

Cited By ~ 5

Author(s):

Y. Evrenosoğlu ◽

K. Mertoğlu

Keyword(s):

Fire Blight ◽

Animal Health ◽

Blight Resistance ◽

Fruit Characteristics ◽

Breeding Programs ◽

Pyrus Communis L ◽

Management Method ◽

Resistant Rootstock ◽

Santa Maria ◽

Harmful Effects

Fire blight is one of the most destructive diseases of pome fruits, especially pears. In current conditions when the demand for organic products is increasing, improvement of resistant rootstock and varieties is becoming important due to the lack of an effective disease management method against fire blight caused by Erwinia amy-lovora as well as the harmful effects of chemicals on environment, human and animal health. The findings of the researchers as to which variety performs well in terms of the transmission of fire blight resistance are quite important for new breeding programs. In the study, three varieties with high commercial value (Magness, Santa Maria and Williams) were identified as the maternal parents and 21 hybridization combinations were made with seven varieties (Akça, Ankara, Conference, Güz, Kaiser Alexandre, Kieffer and Taş) as pollinators. The Magness maternal parent was found superior when compared with the other maternal parents for the variety susceptibility level to fire blight. Apart from the differences in the susceptibility level of 21 different combinations of hybrids to fire blight, the commercially superior ten hybrids (I-15-24, II-13-1, II-13-19, II-13-34, II-13-73, II-27-21, II-27-55, II -32-44, III-22-638, III-27-590) have been determined via the weighted ranking method from the parameters of disease resistance and different fruit characteristics measuring the commercial preference of the fruits such as fruit quality, attractiveness, size, firmness and rustiness

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