European plum ( Prunus domestica L.) is an economically important temperate fruit species and was one of the first crops that attracted human interest ( Faust and Surányi, 1999 ). Its fruits are very popular because it can be used for several
Noémi Makovics-Zsohár, Magdolna Tóth, Dezső Surányi, Szilvia Kovács, Attila Hegedűs, and Júlia Halász
Sima Panahirad, Rahim Naghshiband-Hassani, Babak Ghanbarzadeh, Fariborz Zaare-Nahandi, and Nasser Mahna
Plums ( Prunus domestica L.) are a good source of antioxidants, anthocyanin, phenolic compounds, nutritional elements, and some vitamins ( Cevallos-Casals et al., 2006 ) that may benefit human health ( Gil et al., 2002 ; Wargovich, 2000 ), but
Jean-Michel Hily, Michel Ravelonandro, Vern Damsteegt, Carole Bassett, Cesar Petri, Zongrang Liu, and Ralph Scorza
chain reaction (PCR) analysis, using primers specific to the PPV-CP gene, of a subset of seedlings surviving under kan selection (17 plants) indicated a selection efficiency of 94%. Prunus domestica transformation using seeds of ‘Stanley’ followed
Ralph Scorza, Michel Ravelonandro, Ann Callahan, Ioan Zagrai, Jaroslav Polak, Tadeuz Malinowski, Mariano Cambra, Laurene Levy, Vern Damsteegt, Boris Krška, John Cordts, Dennis Gonsalves, and Chris Dardick
Prunus persica (GF305 peach seedlings), Prunus domestica (European plum seedlings), Prunus myrobalan , and GF 8-1 ( Prunus cerasifera × P. munsoniana ). An overview of the development of ‘HoneySweet’ plum and molecular characterization can be found
Carolyn J. DeBuse, Douglas V. Shaw, and Theodore M. DeJong
Controlled pollinations were made using 20 elite selections from the University of California, Davis, Prunus domestica (european plum) breeding program as parents. These parents were used to generate 11 self-pollinated progenies with an inbreeding coefficient (F) of 0.5, 10 full-sibling progenies (F = 0.25), and 11 progenies from among nonrelated parents (F = 0). Seven additional progenies were chosen as a random-mating control set within the parental group; progenies in the control set had accumulated a range of current inbreeding coefficients (average F = 0.23) over two to five generations with intervening cycles of selection. Survival percentages were 85, 82, and 74 for the full-sib progeny, control set progeny, and selfed progeny, respectively, relative to nonrelated progeny. Two months after germination the percent decrease in the growth trait means for the selfed progeny compared to the nonrelated progeny ranged from 14% to 30% whereas growth trait means for full-sib progeny decreased from 1% to 9% compared to nonrelated progeny. The percent decrease for growth trait means of the selfed progeny after completing one season of growth in the field (10 months) was similar to that observed after 2 months, ranging from 14% to 28% compared to nonrelated progeny, whereas the decrease in full-sib progeny trait means was somewhat greater, ranging from 6% to 20%. Regression analysis of all growth traits on current-generation rates of inbreeding indicated a significant negative linear relationship (P = 0.0011 to 0.0232). No significant relationships were found between accumulated Fs and growth trait means of the control set progenies and the nonrelated progenies after 2 months in the greenhouse or one season growing in the field, suggesting that selection between breeding cycles decreased inbreeding depression.
Dineshkumar Selvaraj, Sherif Sherif, Mohd Sabri Pak Dek, Gopinadhan Paliyath, Islam El-Sharkawy, and Jayasankar Subramanian
) Flowers collected from five lines of transgenic plants expressing Prunus domestica chalcone synthase (Pd-CHS), P. domestica dihydroflavonol reductase (Pd-DFR), P. domestica anthocyanin synthase (Pd-ANS), and P. domestica UDP-glucose flavanoid 3-O
Ann M. Callahan, Chris Dardick, and Ralph Scorza
-Fernandez, R. Matilla, A.J. Roriguez-Gacio, M.C. Fernandez-Otero, C. de la Torre, F. 2007 The polygalacturonase gene PdPG1 is developmentally regulated in reproductive organs of Prunus domestica L. subsp. insititia
Moritz Knoche, Eckhard Grimm, Andreas Winkler, Merianne Alkio, and Jürgen Lorenz
peel disorder in sweet cherry: Mechanism and triggers Postharvest Biol. Technol. 137 119 128 Stösser, R. Neubeller, J. 1985 Histologische und chemische Untersuchung der “Halswelke” bei der Hauszwetsche ( Prunus domestica L.) Gartenbauwissenschaft 50 97
Jean-Michel Hily, Ralph Scorza*, and Michel Ravelonandro
We have shown that high-level resistance to plum pox virus (PPV) in transgenic plum clone C5 is based on post-transcriptional gene silencing (PTGS), otherwise termed RNA silencing (Scorza et al. Transgenic Res. 10:201-209, 2001). In order to more fully characterize RNA silencing in woody perennial crops, we investigated the production of short interfering RNA (siRNA) in transgenic plum clones C3 and C5, both of which harbor the capsid protein (CP) gene of PPV. We used as a control, plum PT-23, a clone only transformed with the two marker genes, NPTII and GUS. We show in the current report that C5 constitutively produces two classes of siRNA, the short (21-22 nucleotides) and long (≈27 nucleotides) species in the absence of PPV inoculation. Transgenic susceptible clone C3 and the control clone PT-23, when healthy, produce no siRNA. Upon infection, these clones produce only the short siRNA (21-22 nt). This siRNA production suggests that plum trees naturally respond to virus infection by initiating PTGS or PTGS-like mechanisms. This study also suggests that high-level virus resistance in woody perennials may require the production of both the short and long size classes of siRNA, as are produced by the resistant C5 plum clone.
S.M. Southwick, W. Olson, and J. Yeager
Soil applied potassium (K) may not alleviate K deficiency in fine textured California soils when high numbers of prunes per tree are produced leading to leaf necrosis and limb death. Because K demand is increased by fruit, K nitrate (KN) sprays appear to be a corrective option for growers in this situation. Our objectives were to determine best seasonal KN spray liming strategies to minimize K deficiency, quantify K uptake into leaves after spray and to evaluate spray effects on productivity. Results indicated that regardless of spray timing leaf K was increased by approximately 0.3% and three weeks later decreased 0.2%. Average leaf K in sprayed trees was 0.7% higher than untreated trees at harvest. Fruit fresh to dry weight ratios were lower (better) from summer sprayed trees than spring. Summer KN sprayed trees had yield efficiencies equal to those having soil applied K. Fruit size was similar regardless of K application method. Foliar KN sprays may be a viable K augmentation to soil application in heavy crop years on fine textured soils.