traits ( MartÃnez-GarcÃa et al., 2013 ). Breeders, including peach breeders, are seeking ways to increase the cost-effectiveness of their programs. Each breeding program is different, and thus the cost-effectiveness of DNA-informed breeding in apple
North Carolina peach breeding program, in which germplasm not related to Chinese Cling was often used to broaden the genetic base of the program. The previously described Highlighter gene may itself be relatively unique among peach cultivars. We have
This manuscript is dedicated to the late Wang Zu-Hua for his extraordinary contributions to peach breeding. I thank D.W. Rammng and Jin Zewan for their assistance in revising this manuscript.
Three ornamental peaches and one ornamental nectarine were released in 1992 from the Arkansas peach breeding program. `Tom Thumb' is a red-leaf dwarf peach with attractive foliage that is retained throughout summer. `Leprechaun' is a green-leaf dwarf nectarine with small but attractive, freestone fruits. `Crimson Cascade' and `Pink Cascade' are red-leaf peaches with trees of standard size that exhibit a weeping growth habit. `Crimson Cascade' produces double flowers that are dark red while `Pink Cascade' double flowers are pink. The attractive plants of these cultivars should be of value in home landscapes.
139 ORAL SESSION 40 (Abstr. 275–281) Fruits: Breeding and Genetics
Breeding to adapt temperate-zone fruit to subtropical production areas has been a formidable objective because so many different characteristics have to be changed, most of which are controlled by many genes. Recurrent selection is the only breeding method that can accomplish the required wholesale reorganization of the physiology of the plant. The principles of recurrent selection, developed and tested using short-generation organisms like fruit flies, rats, and maize, have been applied to the development of low-chill highbush blueberry (V. corymbosum L.) and peach [Prunus persica (L.) Batsch.] cultivars for northern and central Florida. These principles include using many parents per generation of crosses, minimizing the time between cycles of selection, and selecting simultaneously for all heritable traits that are important in the final product, with traits of highest economic importance and highest heritability being given the highest weight in selecting parents. Many characteristics changed during the breeding of low-latitude peach and highbush blueberry cultivars, including chill requirement, photoperiod response, resistance to various disease and insect pests, fruit chemistry, and growth patterns during a long growing season.
Promising white peach and nectarine selections, many with nonmelting flesh, from the Univ. of Arkansas breeding program were evaluated for fruit quality and flavor. About 20 kg of fruit, consisting of mature ripe and ripe stages, were harvested from 4- to 7-year-old trees in Arkansas and transported to Lane, Okla. Fruit were divided into two boxes per selection. One box was held at 5 °C for 8 days, then transferred to 20 °C for 4 days to induce chilling injury and was evaluated for storage quality. The other box was held at 20 °C for 4 days and fruit used for taste panels. Of the 14 nectarine and 12 white peach selections evaluated, one nectarine and four white peach selections had slight chilling injury. Flesh firmness of selections after storage ranged from 6 to 50 N. Taste panelist scores indicated that sweetness was associated with peach flavor in both nectarines and white peaches and that overall acceptability was dependent on sweetness, peach flavor, and low tartness. Ten of the white peach selections were equal to or better in overall acceptability compared to `Summer Pearl' and `Carolina Belle' cultivars included in the study. Panelists did not consider firm texture to be detrimental to overall acceptability. Results indicate that many of the breeding lines used in this study had fruit equal to or better than currently available cultivars in storage life, firmness, and sweetness.
Abstract
Stone fruit breeding programs by the USDA have been a major source of improved peach and nectarine cultivars. A nearly complete turnover has occurred in locations, personnel, and cultivars in the 23 years since Havis reviewed these programs (15). It is appropriate to review the changes and note the progress that has been made in the last 2 decades.
Abstract
A 10-year analysis of the high-density nursery (HDN) in the breeding of low-chilling peach and nectarine [Prunus persica (L.) Batsch] cultivars indicated selection was effective during the first cropping year for chilling requirement, fruit development period, size, color, shape and firmness but not for crop load, which needs to be evaluated at normal spacing over several years. The HDN system effectively has advanced the breeding program by promoting short generation time, reducing labor and space, and allowing for rating of some characters within 2 years from seed.
1 Current address: EMBRAPA/CPAMN, Cx. Postal 1, Teresina, PL, Brazil. This paper represents a portion of a PhD dissertation in plant breeding submitted by the senior author. The cost of publishing this paper was defrayed in part by the payment of