Flat peach and flat nectarine (Prunus persica L. Batsch.) production in Spain started from local cultivars at marginal sites, mainly in the Ebro Valley and Murcia regions. At the end of the 1990s, the introduction of improved cultivars from France and Italy, with more red skin color coverage and better regular shape, fruit size, and stylar cavity closure, together with superior handling and transport conditions led the Spanish peach sector to develop this fruit type on a commercial scale. Currently, Spain is the largest European producer and exporter of flat peach and nectarine, offering a wide range of cultivars covering the producing period from May to September. In 2020, a total of 10.200 ha for flat peach and 481 ha for flat nectarine together produced 263.651 t (20% of the total peach production) (MAPAMA, 2022).
To guarantee adaptation to local growing conditions (Font i Forcada et al., 2021a), several national breeding programs started to develop new flat peach and flat nectarine cultivars. One of these breeding programs is the ASF-IRTA breeding program, which is located at Gimenells (Lleida) in the Ebro Valley (northeastern Spain), which is a major region of peach production in Spain (Batlle et al., 2012; Cantín et al., 2017). It was started in 2004, with the objective of developing new cultivars adapted to chilling between 1000 and 1500 chill units or between 42 and 75 chill portions and warm conditions similar to the Mediterranean area (32 °C mean daily summer temperature and 300–400 mm of annual rainfall). It aimed to produce high-quality fruits, both at harvest and after cold storage, with the ultimate goal of satisfying consumers (Font i Forcada et al., 2021a, 2021b). As a result of this collaborative effort, the ASF-IRTA scion peach breeding program has already released the SUBLOR (one flat yellow-fleshed peach), SUBLIM (six flat white-fleshed peach), and PERLA (two flat white-fleshed nectarine) series. These nine new flat peach and nectarine cultivars produce highly attractive yellow-fleshed or white-fleshed fruits with high coverage of red skin, a balanced or acid flavor, sweet taste, and good flesh firmness. The harvesting calendar of these series will be progressively completed with new future releases.
Origin
Regarding SUBLOR flat peaches, ‘SUBLOR 2601’ was a seedling from 01.29E.17 NbPl × open pollination. For SUBLIM flat peaches, ‘SUBLIM 2801’ was a seedling from ASF 01.10.64.02 PbPl × ASF 02.10.66.02 Nb, ‘SUBLIM 3001’ was from PBP 01.29E.44 × open pollination, ‘SUBLIM 3002’ was from ASF 01.24.88.01 PbPl × ASF 02.10.66.02 Nb, ‘SUBLIM 3101’ was from PBP 01.29E.33 × open pollination, ‘SUBLIM 3201’ was from PBP 01.29E.44 × open pollination, and ‘SUBLIM 3801’ was from PBP 01.29E.44 × open pollination. For PERLA flat nectarine series, ‘PERLA 2501’ and ‘PERLA 3501’ were from 03.24.43 PbPl × ASF 02.10.66.02 Nb.
Description
Tree vigor, tree habit, and flower density were described according to the International Union for the Protection of New Varieties and Plants (UPOV, 2010) and the Community Plant Variety Office (CPVO, 2015).
SUBLOR flat peach (yellow-fleshed), with ‘SUBLOR 2601’ being the only one of this series, is moderately vigorous and has a spreading habit. Under the growing conditions of the Ebro Valley, it blooms during March and has medium flower density. It is considered an early cultivar, with its harvest time being during the third week of June (Supplemental Table S1).
SUBLIM flat peach series (white-fleshed) are moderately vigorous and have a spreading habit, except for ‘SUBLIM 3101’ and ‘SUBLIM 3201’, which have an upright to spreading habit. Under the growing conditions of the Ebro Valley, full bloom occurs during March, and harvesting dates are between the end of June and mid-September (16 June–15 Sept.) (Supplemental Table S1).
PERLA flat nectarine series (white-fleshed) is moderately vigorous and has an upright to spreading habit. Under local growing conditions, full bloom occurs during March, and harvesting dates are between the beginning of July and mid-September (9 July–16 Sept.) (Supplemental Table S1). Differently from other commercial cultivars, there is no need for flower thinning because adequate fruit thinning will effectively optimize fruit size.
Performance
All nine cultivars were originally selected as seedlings grown at selection plots and then grafted (two or three replicates per selection) onto ‘Cadaman’ rootstock after selection (the fifth most used rootstock in the Ebro Valley) (Reig et al., 2013). The location and orchard management have been described by Font i Forcada et al. (2021a, 2021b). The data presented in Supplemental Table S1 summarize the average values for 6 years on full-sized trees.
Maturity time.
SUBLIM 2801 and SUBLOR 2601 are early-season cultivars, whereas the rest of the cultivars are midseason cultivars, except for ‘SUBLIM 3801’ and ‘PERLA 3501’, which are considered late-season cultivars (Supplemental Table S1).
Yield.
Trees were harvested during one or two picks separated by 4 to 6 d. Then, all fruits were graded as reported by Font i Forcada et al. (2021a, 2021b). Under the growing conditions of the Ebro Valley, except for the midseason ‘SUBLIM 3001’, which had a small fruit size but great yield, the rest of the cultivars stood out for their high productivity and good fruit size, regardless of their harvesting season (Supplemental Table S1).
Fruit quality.
Twelve fruits per cultivar were used for quality determinations. All cultivars were sweet, aromatic, firm, and melting (Supplemental Table S1). All the fruit evaluated had more than 80% red skin coverage, with a perfect stylar cavity closure, except for ‘PERLA 2501’, which showed an unperfected stylar cavity closure (Supplemental Table S1, Fig. 1), which never implied postharvest problems caused by fungus infections. Skin lenticels are not visible on both PERLA cultivars (Fig. 1). It should be noted that hot climates such as that of the Ebro Valley are conducive to the development of lenticels on fruit skin. In addition, this defect is related to wood aging. However, this issue does not seem to affect these new cultivars.
Typical fruit appearance at the commercial ripening stage: ‘SUBLOR 2601’ (A); ‘SUBLIM 2801’ (B); ‘SUBLIM 3001’ (C); ‘SUBLIM 3002’ (D); ‘SUBLIM 3101’ (E); ‘SUBLIM 3201’ (F); ‘SUBLIM 3801’ (G); ‘PERLA 2501’ (H); and ‘PERLA 3501’ (I).
Citation: HortScience 57, 10; 10.21273/HORTSCI16699-22
Typical fruit appearance at the commercial ripening stage: ‘SUBLOR 2601’ (A); ‘SUBLIM 2801’ (B); ‘SUBLIM 3001’ (C); ‘SUBLIM 3002’ (D); ‘SUBLIM 3101’ (E); ‘SUBLIM 3201’ (F); ‘SUBLIM 3801’ (G); ‘PERLA 2501’ (H); and ‘PERLA 3501’ (I).
Citation: HortScience 57, 10; 10.21273/HORTSCI16699-22
Typical fruit appearance at the commercial ripening stage: ‘SUBLOR 2601’ (A); ‘SUBLIM 2801’ (B); ‘SUBLIM 3001’ (C); ‘SUBLIM 3002’ (D); ‘SUBLIM 3101’ (E); ‘SUBLIM 3201’ (F); ‘SUBLIM 3801’ (G); ‘PERLA 2501’ (H); and ‘PERLA 3501’ (I).
Citation: HortScience 57, 10; 10.21273/HORTSCI16699-22
Postharvest performance.
The sample size and methodology have been described by Font i Forcada et al. (2021a, 2021b). All cultivars showed good postharvest performance after 30 d at 0.5 °C plus 2 d at 20 °C.
Availability
The cultivars are protected by the Community Plant Varieties Office with the following registration numbers: 20191202 for ‘SUBLOR 2601’; 20191135 for ‘SUBLIM 2801’; 20191200 for ‘SUBLIM 3001’; 20191215 for ‘SUBLIM 3002’; 20191213 for ‘SUBLIM 3101’; 20201225 for ‘SUBLIM 3201’; 20191201 for ‘SUBLIM 3801’; 20191214 for ‘PERLA 2501’; and 20203072 for ‘PERLA 3501’. Virus-free plants are available from nurseries authorized by the IRTA (Spain). The plant material was laboratory-tested to provide negative results for the following: Agrobacterium tumefaciens [reverse-transcriptase polymerase chain reaction (RT-PCR)]; Apple Chlorotic Leaf Spot Virus (ACLSV) [enzyme-linked immunosorbent assay (ELISA)]; Candidatus Phytoplasma prunorum (RT-PCR); Peach Latent Mosaic Viroid (PLMVd) (Molecular Hybridisation); Plum Pox Virus (PPV) (ELISA); Prune Dwarf Virus (PDV) (ELISA); Prunus Necrotic Ring Spot Virus (PNRSV) (ELISA); Xanthomonas arboricola pv. pruni (RT-PCR); and Xylella fastidiosa (RT-PCR).
Literature Cited
Batlle, I., Fontich, C., Lozano, L., Iglesias, I., Reig, G., Alegre, S., Echeverría, G., de Herralde, F., Claveria, E., Dolcet-Sanjuan, R., Carbó, J., Bonany, J., Maillard, A. & Maillard, L. 2012 The peach breeding programme IRTA-ASF: Aiming for high fruit quality Acta Hort. 940 75 78 https://doi.org/10.17660/ActaHortic.2012.940.8
Cantín, C.M., Fontich, C., Batlle, I., Iglesias, I., Dolcet-Sanjuan, R., Alegre, S., Carbó, J., Bonany, J., Maillard, A. & Maillard, L. 2017 The joint IRTA-ASF peach breeding program: Outstanding quality fruit adapted to the Mediterranean conditions Acta Hort. 1172 151 154 https://doi.org/10.17660/ActaHortic.2017.1172.29
CPVO 2015 Protocol for tests on distinctness, uniformity and stability TP/053/2 Rev
Font i Forcada, C., Reig, G., Fontich, C., Batlle, I., Alegre, S., Cantín, C.M., Eduardo, I., Carbó, J., Maillard, A., Maillard, L. & Bonany, J. 2021a TERRAM and LUX Series: Four yellow-fleshed and three white-fleshed peaches HortScience 56 9 1130 1131 https://doi.org/10.21273/HORTSCII5882-21
Font i Forcada, C., Reig, G., Fontich, C., Batlle, I., Alegre, S., Cantín, C.M., Eduardo, I., Carbó, J., Maillard, A., Maillard, L. & Bonany, J. 2021b MAGNA and BLANQ Series: Four yellow-fleshed and three white-fleshed peaches HortScience 56 9 1132 1133 https://doi.org/10.21273/HORTSCII5883-21
MAPAMA 2022 (Accessed January 2022) https://www.mapama.gob.es/es/
Reig, G., Alegre, S., Gatius, F. & Iglesias, I. 2013 Agronomical performance under Mediterranean climatic conditions among peach [Prunus persica (L.) Batsch] cultivars originated from different breeding programmes Scientia Hort. 150 267 277 https://doi.org/10.1016/j.scienta.2012.11.006
UPOV 2010 International Union for the protection of new varieties of plants. Guide-lines for the conduct of tests for distinctness, uniformity and stability to peach (Prunus persica (L.) Batsch) TG/53/7 Rev
Agronomic and fruit quality characteristics of the SUBLOR and SUBLIM flat peach series, PERLA flat nectarine series, and reference commercial cultivars ‘Platibelle’ and ‘Flatstar’ trialed at IRTA, Gimenells, Lleida, Spain.
