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Check digit technology is frequently used in commercial applications such as shipping labels and credit cards to flag errors in numbers as they are used. Most systems use modular arithmetic to calculate a check digit from the digits in the identification number. Check digits are little used in horticultural research because the guidelines for implementing them are neither well known nor readily accessible. The USDA-ARS stone fruit breeding program at Byron, Ga., plants thousands of trees annually, which are identified using a 2-digit year prefix followed by a sequential number that identifies the tree location in the rows. Various records are taken over the life of the tree including bloom and fruit characteristics. Selected trees are propagated and tested further. To improve the accuracy of our records we have implemented a system which uses a check number which is calculated from the identification number and then converted to a letter that is added onto the end of the identification number. The check letter is calculated by summing the products of each of the digits in the number multiplied by sequential integers, dividing this sum by 23, and converting the remainder into a letter. Adding a single letter suffix is a small change and does not add much complexity to existing data collection. The types of errors caught by this system are discussed, along with those caught by other common check digit systems. Check digit terminology and theory are also covered. [ABSTRACT FROM AUTHOR]

Roots of dormant peach trees can grow when soil temperatures are >7 °C, which commonly occurs in the southeastern U.S. during the winter. In our tests, root growth on 1-year-old nursery trees was minimal at 7 °C, and increased with temperature up to at least 16 °C, but rootstocks varied greatly in their regeneration at a given temperature. Trees on seedling rootstocks of 'Guardian™', 'Halford' and 'Lovell' regenerated roots more slowly than those on 'Nemaguard' at soil temperatures >7 °C. The regeneration rates mirrored the relative susceptibility of these rootstocks to peach tree short life syndrome in the southeastern U.S., which is associated with parasitism by ring nematode. [ABSTRACT FROM AUTHOR]

Prunus ferganensis (Kost. & Riab) Kov. & Kost, a close relative of cultivated peach (Prunus persica (L.) Batsch.), is native to arid regions of central Asia. A distinguishing feature of P. ferganensis is its prominent, elongated, unbranched pattern of leaf venation. To determine whether the long-vein trait could be used as a marker in breeding for drought tolerance, we investigated the association between this trait and the leaf morphological and physiological parameters related to drought response in P. ferganensis, P. persica and two interspecific hybrids, one with the long-vein trait (BY94P7585) and one without (BY94P7589). The four genotypes were grafted onto “Guardian” peach rootstock and half of the plants were assigned to a drought treatment in which irrigation was limited to 25–50% of the evapotranspiration (ET) rate measured in the remaining well-watered plants, which were irrigated to runoff daily. The drought treatment reduced photosynthesis and leaf conductance by 49–83% and reduced total leaf area per plant by 17–24%, but generally did not affect mid-morning leaf water potential. Leaf gas exchange did not differ among genotypes in either treatment. Sorbitol accumulated in mature leaves in response to drought, but neither its amount nor its metabolism varied systematically with climatic adaptation among genotypes. Accumulation of transport sugars was highest in P. ferganensis, indicating that growth reduction may represent an important strategy for coping with drought in this species. Prunus ferganensis and the hybrids had higher ET than P. persica, and seemed to use water opportunistically, maintaining high gas exchange rates and consequently high ET when water was available, and avoiding low water potentials through stomatal closure as soil water declined. Leaf size (cm2 leaf−1) and specific leaf area (cm2 g−1 dry mass) were lower in P. ferganensis and the hybrids than in P. persica. We conclude that the long-vein trait is not a reliable marker for drought tolerance, but leaf traits of P. ferganensis such as size and specific leaf area may be useful in P. persica breeding programs targeting drought tolerance. [ABSTRACT FROM PUBLISHER]

Individual peach [Prunus persica (L.) Batsch] trees were monitored prior to the development of peach tree short life (PTSL) to determine if nutrient deficiencies and/or imbalances were causative factors in PTSL development. Twig concentrations of Al, Ca, Fe, K, Mg, Mn, P, and Zn were determined in March and December of each year. In the final year of the study, elemental concentrations were also determined in April after visual symptoms of PTSL were evident. Elemental concentrations in healthy trees were compared to concentrations in trees which eventually died due to PTSL. Significant differences in P and K concentrations between PTSL and healthy trees were found in 1986 and 1987 but no consistent trends were apparent. The greatest differences between PTSL and healthy trees were found after visual symptoms of PTSL appeared. In most cases, elemental concentrations were greater in trees exhibiting PTSL symptoms than in healthy trees. The data indicate that differences were symptoms of the PTSL complex and not a cause in the development of the disease. [ABSTRACT FROM PUBLISHER]

The article provides information on the Scarletprince and Julyprince peach cultivars bred by the U.S. Agricultural Research Service in Byron, Georgia. Scarletprince resulted from the open-pollination of the seeds of Blazeprince while Julyprince resulted from a cross of L75-A50-20 and BY89P2787 varieties. The leaf glands of Scarletprince are reniform while its blossoms have large and showy pink petals. The trees of Julyprince require ≈850 hours of chilling below 7 ° Celsius to break the bud rest period in climates similar to Byron.

The article describes the Early Augustprince and Augustprince peach cultivars. They were bred at the Southeastern Fruit and Tree Nut Research Laboratory of the U.S. Agricultural Research Service in Byron, Georgia by horticulturist W. R. Okie in 1995. The leave glands of Early Augustprince are globose while its trees are moderately resistant to bacterial spot disease. The flowers of Augustprince have showy pink petals and self-fertile.

Profiles five U.S.-based stone-fruit breeders. Stanley Johnston; Catherine Bailey; Franklin Correll; John Weinberger; Ralph Sharpe.

Peach tree short life (PTSL) is associated with the presence of ring nematode, Mesocriconema xenoplax, and poor orchard management practices. Finding a noncommercial field site to evaluate rootstocks for PTSL resistance is increasingly difficult. The time needed to create a PTSL test site was investigated. In 1994, a site not planted in peaches for >80 years was identified in Byron, Ga. Analysis of preplant soil samples revealed that there were no M. xenoplax on the site. One-third of the land was planted to peach and infested with 1600 ring nematodes per tree in Spring 1994 (P2) and another one- third in Spring 1995 (P1). The remaining one-third of the land received no trees or ring nematode and served as the control (F2). In Fall 1995, trees were removed from P1 and P2 plots and all treatments were replanted to peach in 1996. In 1997, tree death resulting from PTSL occurred only in P2 (7%). By 2000, PTSL tree death reached 41% in P2,16% in P1, and 4% in F2 plots. Nematode populations were higher (P < 0.05) in P1 (649 ring nematode/ 100 cm³ soil) than in F2 (221 ring nematode/100 cm³ soil) plots, whereas populations in P2 (300 ring nematode/100 cm³ soil) plots did not differ from those in P1 or F2 plots. Establishing a PTSL screening site was possible 3 years after M. xenoplax introduction; PTSL development among treatments in the subsequent planting was dependent upon cumulative population exposure of trees to M. xenoplax. [ABSTRACT FROM AUTHOR]

The ubiquitous tripeptide glutathione (GSH) is a critical component of the endogenous antioxidant defense system. Tissue GSH concentrations and redox status (GSH/GSSG) are genetically controlled, but it is unclear whether interactions between genetic background and diet affect GSH homeostasis. The current study tested the hypothesis that a high-fat diet regulates GSH homeostasis in a manner dependent on genetic background. At 4 months of age, female mice representing 3 obesity-prone inbred strains-C57BL/6J (B6), DBA/2J (D2), and AKR/J (AKR)-were randomly assigned to consume a control (10% energy from fat) or high-fat (62% energy from fat) diet for 10 weeks (n=5/diet per strain). Tissue GSH levels, GSSG levels, and GSH/GSSG were quantified, and hepatic expression of GSH-related enzymes was evaluated by quantitative reverse transcription polymerase chain reaction. The high-fat diet caused a decrease in hepatic GSH/GSSG in D2 mice. In contrast, B6 mice exhibited a decrease in GSSG levels in the liver and kidney, as well as a resultant increase in renal GSH/GSSG. AKR mice also exhibited increased renal GSH/GSSG on a high-fat diet. Finally, the high-fat diet induced a unique gene expression response in D2 mice compared with B6 and AKR. The D2 response was characterized by up-regulation of glutamate-cysteine ligase modifier subunit and down-regulation of glutathione reductase, whereas the B6 and AKR responses were characterized by up-regulation of glutathione peroxidase 1. Two-way analysis of variance analyses confirmed several diet-strain interactions within the GSH system, and linear regression models highlighted relationships between body mass and GSH outcomes as well. Overall, our data indicate that dietary fat regulates the GSH system in a strain-dependent manner., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Anthocyanins are a class of phytochemicals that have generated considerable interest due to their reported health benefits. It has been proposed that commonly consumed anthocyanins, such as cyandin-3-O-β-glucoside (C3G), confer cellular protection by stimulating biosynthesis of glutathione (GSH), an endogenous antioxidant. Currently, it is unknown whether the health effects of dietary anthocyanins are genetically determined. We therefore tested the hypothesis that anthocyanin-induced alterations in GSH homeostasis vary by genetic background. Mice representing five genetically diverse inbred strains (A/J, 129S1/SvImJ, CAST/EiJ, C57BL/6J, and NOD/ShiLtJ) were assigned to a control or 100mg/kg C3G diet (n=5/diet/strain) for six weeks. GSH and GSSG levels were quantified in liver, kidney, heart, pancreas, and brain samples using HPLC. The C3G diet promoted an increase in renal GSH concentrations, hepatic GSH/GSSG, and cardiac GSH/GSSG in CAST/EiJ mice. C3G treatment also induced an increase in pancreatic GSH/GSSG in C57BL/6J mice. In contrast, C3G did not affect GSH homeostasis in NOD/ShiLtJ mice. Surprisingly, the C3G-diet caused a decrease in hepatic GSH/GSSG in A/J and 129S1/SvImJ mice compared to controls; C3G-treated 129S1/SvImJ mice also exhibited lower total glutathione in the heart. Overall, we discovered that C3G modulates the GSH system in a strain- and tissue-specific manner. To our knowledge, this study is the first to show that the redox effects of anthocyanins are determined by genetic background., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Host-parasite relationships of Criconemella xenoplax and C. ornata on Nemaguard peach and common bermudagrass were determined in the greenhouse. Criconemella xenoplax reproduced on peach and reduced root volume, height, and dry stem weight after 6 months, compared with the noninfested check. Numbers of C. ornata did not increase on peach or influence peach growth, but they did reduce dry top weight and root volume of common bermudagrass, compared with C. xenoplax. Criconemella xenoplax and C. ornata produced the enzyme beta-glucosidase and were capable of metabolizing prunasin, but only C. xenoplax produced beta-cyanoalanine synthase to detoxify the cyanide released from prunasin. The apparent inability of C. ornata to detoxify cyanide is one explanation why numbers of this species did not increase on peach. Criconemella xenoplax and C. ornata can be distinguished by using stylet length, vaginal configuration, and shape of the anterior head region.

Percentage of mortality, growth suppression, and changes in free amino acid and reducing sugar content in root and (or) stem tissue of Nemaguard peach seedlings were studied in the greenhouse in relation to time and eight different initial population densities (Pi) of Criconemella xenoplax. After 90 and 180 days, free amino acid content in root tissue significantly increased with increasing nematode numbers. Suppression of root volume, dry root and stem weight, height increase, plant survival, and content of reducing sugars in root tissue were detected at 180 and 270 days and following pruning. All criteria were negatively correlated with nematode Pi. Changes in growth, metabolic parameters, and survival percentage were attributed to Pi density of C. xenoplax, duration of the experiment, and nematode reproduction rate.