US 20020138884P1 (19) United States (12) Plant Patent Application Publication (10) Pub. N0.: US 2002/0138884 P1 Zaiger et al. (43) Pub. Date: Sep. 26, 2002

(54) SELECT MYROBALAN TREE ’RI-1’ Publication Classi?cation

(50) Latin Name: (51) 1111.07 ...... A01H 5/00 Varietal Denomination: (52) US. Cl...... PLT/180 (57) ABSTRACT (76) Inventors: Chris Floyd Zaiger, Modesto, CA (US); Gary Neil Zaiger, Modesto, CA A new and distinct variety of Myrobalan tree (Prunus (US); Leith Marie Gardner, Modesto, cerasifera). Its novelty consists of the following unique CA (US); Grant Gene Zaiger, combination of features that are desirable in a new interstock Modesto, CA (US) when growing cherries: 1. Decreasing the height of the cherry tree for more Correspondence Address: economical harvesting. Michelle Bos 2. Providing earlier production of fruit when growing Stratton Ballew PLLC cherries with the new interstock variety on Citation 213 South 12th Avenue Rootstock. Yakima, WA 98902 (US) 3. Increasing the number of rootstocks available for (21) Appl. N0.: 09/814,582 cherries. 4. Improving the opportunity to match soil type with (22) Filed: Mar. 21, 2001 the desired rootstock by using an interstock.

BACKGROUND OF THE VARIETY located near Modesto, Calif. as a selection from seed of open [0001] In the ?eld of plant genetics, we conduct an exten pollinated populations of Myrobalan rootstocks. The exact sive and continuing plant-breeding program including the parentage of the new variety is unknown. We planted and organization and asexual reproduction of orchard trees, and maintained a large group of these open pollinated of which plums, peaches, nectarines, apricots, cherries, Myrobalan seedlings growing on their own root system in our experimental orchard. We budded and grafted these interspeci?cs and rootstocks are exemplary. It was against this background of our activities that the present variety of seedlings to various rootstocks and various varieties of rootstock-interstock was originated and asexually repro cherries (Prunus avium), searching for an interstock between the various species. We experienced some success duced by us in an experimental orchard located near Modesto, Stanislaus County, Calif. with several combinations, but one seedling, now known as ‘RI-1’, showed particular promise as an interstock. That Prior Varieties seedling was tested by budding and grafting and found to be compatible with cherries and several rootstocks, as was thus [0002] Among the existing varieties of rootstocks which selected for asexual propagation and commercialization as are known to us, and mentioned herein, are Nemaguard an interstock for use with cherry scion wood. The new Rootstock (non-patented), Atlas Rootstock (U.S. Plant Pat. interstock is graft compatible with a variety of prunus No. 8913), Viking Rootstock (U.S. Plant Pat. No. 8912), rootstocks, which allows growers to select the most desir Citation Rootstock (U.S. Plant Pat. No. 5112), MaZZard able rootstock for a particular type of soil. Rootstock (non-patented), and Mahaleb Rootstock (non patented). Asexual Reproduction of the Variety Origin of the Variety [0006] Asexual reproduction of the new and distinct vari [0003] It is well known that sweet cherry trees are com ety of Myrobalan tree was by budding to Citation Rootstock patible with a very limited number of rootstocks for com (U.S. Plant Pat. No. 5112) as performed by us in our mercial production. For many years, the primary rootstocks experimental orchard located near Modesto, Calif., and available for the production of commercial cherry trees have shows that reproductions run true to the original tree and all been Mahaleb (non-patented) and MaZZard (non-patented). characteristics of the tree and its fruit are established and Both of these varieties are undesirably tall, and have a long transmitted through succeeding asexual propagations. juveninity period, delaying production of fruit for ?ve to Summary of the New Variety seven years. Additionally, Mahaleb is susceptible to phy tophthora root rot and over cropping, which results in small [0007] The new variety of Myrobalan tree (Prunus fruit siZe. MaZZard is a stronger tree with lighter production, cerasifera) is of medium siZe, moderately vigorous, upright but is even taller than Mahaleb. in growth and graft compatible with a moderate range of prunus species, which makes it available to be used as an [0004] Due to the limitations of the rootstocks presently interstock between cherries (Prunus avium) and the inter available for commercial cherry trees, we attempted to speci?c rootstock Citation (U.S. Plant Pat. No. 5112) (Pru identify a new interstock that would be compatible with a nus salicinaxPrunus persica). Budding and grafting tests variety of commercially available rootstocks, as well as with show compatibility with the following rootstocks and sci sweet cherry varieties. ons: Nemaguard Rootstock (non-patented), Citation Root [0005] The present new Myrobalan tree (Prunus stock (U.S. Plant Pat. No. 5112), Viking Rootstock (U.S. cerasifera) was originated by us in our experimental orchard Plant Pat. No. 8912), Atlas Rootstock (U.S. Plant Pat. No. US 2002/0138884 P1 Sep. 26, 2002

8913), Craigs Crimson Cherry (U.S. Plant Pat. No. 7320), on an exemplary tree, budded on Citation Interspeci?c EarlisWeet Cherry (U.S. Plant Pat. No. 9783), Royal Rainier Rootstock (U.S. Plant Pat. No. 5112), groWn on Handford Cherry (U.S. Plant Pat. No. 10790) and the following sandy loam soil With Storie Index rating 95, in USDA non-patented cherries: Bing, Van, Rainier, Black Tartarian, Hardiness Zone 9, near Modesto, Calif., With standard Stella, Lapins and 31 seedling selections of cherries in the commercial fruit groWing practices, such as pruning, thin advanced testing stage. We expect that similar compatibility ning, spraying, irrigation and fertiliZation. Color terminol Will be exhibited With other cherry varieties. ogy (except those in common terms) is in accordance With Reinhold Color Atlas by A. Kornerup and J. H. Wanscher. [0008] Cherries groWing on the neW Myrobalan interstock grafted to Citation rootstock (“Citation-Myrobalan-cherry [0013] Tree: composite tree”) have been observed over a fourteen (14) [0014] Size.—Medium to large. Tree pruned year period. We have observed a moderate variability in the severely each Winter to induce proper neW groWth amount of dWar?ng effect Within cherry varieties When for budWood. using the same length of interstock. Decreasing the length of interstock reduces the siZe of the tree in all cherry varieties, [0015] Vig0r.—Moderately vigorous. Tree groWth some varieties With a greater degree of dWar?ng than other of 5 to 6 feet (1.5 to 1.8 m) in height and 3 to 4 feet varieties. The interstock should be at least about four inches (0.9 to 1.2 m) in Width the ?rst groWing season. (approximately 10 cm) in length, and should be no more [0016] Gr0wth.—Upright. Each dormant season than about 18 inches (approximately 46 cm) in length. A 6 tree is cut back to 4 to 6 feet (0.9 to 1.8 m) in inch (approximately 15 cm) interstock is preferable. For height to induce rapid neW groWth for spring example, EarlisWeet Cherry can be reduced to approxi budWood. mately one-third of normal tree siZe and Rainier Cherry reduced to approximately one-half normal tree siZe When [0017] Branching habit.—LoW apical dominance budded to a 6-inch segment of the neW Myrobalan interstock alloWs numerous small branches to create a feath groWing on Citation Rootstock. The combination of the neW ered condition throughout the tree. Myrobalan interstock With Citation Rootstock has increased [0018] Pr0ductivity.—Tree very productive, fruit precociousness With cherries We have tested to start fruit production in the third year. Crop load is relatively heavy. has no commercial value. [0009] The Myrobalan interstock union on the above [0019] Bearer.—Regular. rootstocks, including Citation, is relatively smooth, While [0020] Density.—Dense. Numerous lateral branch the bud union on the cherry scion is more prone to be slightly ing increases density. Tree is cut back to 5 to 6 feet over-groWn. The amount of over groWth varies Within cherry (1.5 to 1.8 m) in dormant season to promote rapid varieties. This same type of overgroWth can be found When groWth for desirable budWood. groWing cherries Without an interstock on standard cherry rootstocks such as Mahaleb. We have had no tree loss With [0021] Hardiness.—Hardy in all stone fruit groW the neW Myrobalan interstock from breaking at bud union of ing areas in California. either cherry or rootstock. [0022] Trunk: [0010] The Citation-Myrobalan-cherry composite tree has [0023] Size.—Medium to large. Circumference 19 been groWn in our test orchards and shoWs promise as inches (48 cm) measured 9 inches (23 cm) above commercial fruit tree. Based on our observations of the ground on a 7 year old tree. Varies slightly With Citation-Myrobalan-cherry composite tree, We expect that soil type, climatic conditions and cultural prac related composite trees Will have similar qualities. Such tices. composite trees could include any of the rootstocks named above, or any prunus or interspeci?c rootstocks that are [0024] Surface texture.—Medium shaggy. Rough compatible With the neW Myrobalan interstock. The com ness increases With age of tree. posite trees could further include any of the sWeet cherry [0025] C0l0r.—BroWn to soot broWn (5-F-4) to varieties named above, or any sWeet cherry varieties that are compatible With the neW Myrobalan interstock. (5-F-5). [0026] Branches: PHOTOGRAPH OF THE VARIETY [0027] Size.—Medium. Average circumference 9 [0011] The accompanying color photographic illustration inches (23 cm), measured 58 inches (147 cm) shoWs typical specimens of the foliage and fruit of the above ground. Crotch angle approximately 30 present neW Myrobalan variety. The illustration shoWs the degrees. upper and loWer surface of the leaves, an exterior and [0028] Surface texture.—NeW groWth smooth. sectional vieW of a fruit divided in its suture plane to shoW Mature groWth medium rough. ?esh color, pit cavity and the stone remaining in place. The photographic illustration Was taken shortly after being [0029] Lenticels.—Medium to large. Average picked and the colors are as true as is reasonably possible in length—1/8“ (3.2 mm); Average Width—1/16“ (1.6 a color representation of this type. mm); Color varies from grayish orange to golden yelloW (5-B-6) to (5-B-8); Numerous—31 in 4 DESCRIPTION OF THE VARIETY square inch (26 sq. cm) surface. [0012] The folloWing detailed botanical description of the [0030] C0l0r.—NeW groWth varies from olive neW Myrobalan tree, its ?oWers, foliage and fruit, is based broWn (4-D-6) on under side to violet broWn on US 2002/0138884 P1 Sep. 26, 2002

upper side exposed to sun; Mature growth varies mm), same height as pistils in mature ?oWer. from light broWn to hair broWn (5 —D-5) to (5 —E-5). Anther color—light yelloW to yelloW (4-A-5) to [0031] Leaves: (4-A-6). [0056] Petals.—Quantity—?ve, alternately [0032] Size.—Small; Average length—1% inches arranged to sepals. Shape—obovate, narroWs at (4.4 cm); Average W1dth—7/8 inch (2.2 cm). point of attachment. SiZe—medium. Average [0033] F0rm.—Ovate. length—23/64 inch (9.1 Average Width—1%4 inch (7.5 Surface edges vary from smooth to [0034] Apex. —Acuminate. slightly scalloped. Color—White (1-A-1). [0035] Base. —Obtuse. [0057] Sepals.—Quantity—?ve, alternately [0036] Margin.—Double serrate. arranged to petals. Glabrous Shape—ovate, some What triangular, tip rounded. Average length—5/32 [0037] Thickness.—Medium. inch (4.0 Average Width at base—3/32 inch [0038] Surface texture.—Upper surface relatively (2.4 Color—broWnish red (10-D-7) on smooth, only slightly indented on upper surface loWer center to grayish green (1-D-5) along outer over leaf vein; LoWer surface relatively smooth, edges. midrib With pinnate veining create small ridges. [0058] P0llen.—Abundant. Unknown as to self [0039] Peti0le.—Color—grayish yelloW (2-B-4); fertility. Unimportant as to value of interstock. Average length- 1%4 inch (7.5 mm); Average [0059] Fragrance.—Very slight. Width—3/64 inch (1.2 [0060] Blooming peri0d.—Date of First Bloom [0040] C0l0r.—Upper surface—green to dark Feb. 27, 2000. Date of Last Bloom Mar. 7, 2000. green (27-F-6) to (27-F-8). LoWer surface—light Varies slightly With climatic conditions. green to jade green (27-E-5) to (27-E-7). [0061] FloWer Stem: [0041] Midvein.—Pronounced; Midvein same Width as petiole for approximately 1/2 of leaf; [0062] Size.—Medium. Average length—15/64 Color—grayish yelloW (2-B-4); Venation—pin inches (6.0 Average Width—3/64 inch (1.2 nate. [0042] Glands.—Eglandular. [0063] C0l0r.—Grayish yelloW (2-C-4). [0043] FloWer Buds [0064] Fruit: [0044] Quantity per spur.—Average quantity 6, [0065] Maturity when described.—Firm ripe, no varies from 1 to 12. commercial value. [0045] Size.—Small. Average length—21/64 inch [0066] Date offruit ripening.—Jun. 22, 1999. Fruit (8.3 Average diameter—13/64 inch (5.2 drops on ground, no commercial value. [0046] Hardiness.—Hardy in all stone fruit groW [0067] F0rm.—Globose, slightly elongated. ing areas of California. GroWn in Zone 9. [0068] Size.—Small. Average diameter axially 15/16 [0047] F0rm.—Plump, free; Varies from conic to to 1 inch (23.8 to 25.4 Average transversely elongated as bud development progresses. Averagein suture Weightplane 3A7.9 to grams.15/16 inch Average (19.0 Weightto 23.8 varies [0048] C0l0r.—White (1-A-1). With quantity of fruit per tree, fertility of soil and [0049] Pedicel.—Average length—2%4 inch (11.5 climatic conditions. Average Width—3/64 inch (1.2 Color— [0069] Suture.—Smooth. Extends from base to grayish green (1-D-5). apex. [0050] FloWers: [0070] Ventral surface—Rounded, smooth. [0051] Devel0pment.—Perigynous, complete, [0071] Apex.—Slight, rounded. single pistol, multiple stamens, ?ve petals and sepals alternately arranged. [0072] Base.—Flat, varies from ?at to slightly retuse. [0052] Size.—Small. Average height—21/64 inch (8.3 Average diameter—55/64 inch (21.8 [0073] Cavity.—Rounded. Very slightly elongated in suture plane. Average depth—1/16 inch (1.6 Average breadth—1/s inch (3.2 [0053] C0l0r.—White (1-A-1). [0074] Stem: [0054] Pistil.—Usually one. Average length—5/16 inch (7.9 Color—White (1-A-1). [0075] Size.—Small. Average length—3/s inch (9.5 Average Width—1/16 inch (1.6 [0055] Stamens.—28 to 31 per ?oWer. Average ?lament length—% inch (6.4 Color—White [0076] C0l0r.—Grayish green to spring green (30 (1-A-1). Average stamen length—17/64 inch (6.7 C-6) to (30-07). US 2002/0138884 P1 Sep. 26, 2002

[0077] Flesh: [0099] Surface.—Pitted throughout. Pits small and relatively uniform. One very shalloW groove on [0078] Ripens. —Even. each side of suture. [0079] Texture.—Firm. [0100] Sides.—Equal. [0080] Fibers.—None. [0101] Tendency t0 split.—None. [0081] Ar0ma.—Slight. [0102] C0l0r.—Light broWn to oak broWn (S-C-S) to (S-D-S) When dry. [0082] Eating quality.—Poor, no commercial [0103] Use: Rootstock interstock for tree siZe control value. With cherries (Prunus avium). [0083] Flav0n—Acid. [0104] Disease Resistance/Susceptibility: No speci?c [0084] Juice.—Moderate. testing for relative plant/fruit disease resistance/suscep tibility has been designed. Under close observation [0085] C0l0r.—Pale yellow to butter yellow (4-A during planting, groWing, and harvesting of fruit, under 4) to (4-A-5). Pit cavity color- golden yelloW normal cultural and groWing conditions near Modesto, (4-B-5). Calif., no particular plant/fruit disease resistance or [0086] Skin: susceptibility has been observed. Any variety or selec tion observed during indexing of plant characteristics, [0087] C0l0r.—YelloW to amber yelloW (4-A-6) to With abnormal ?ngus, bacterial, virus, or insect suscep (4-B-6). tibility is destroyed and eliminated from our breeding [0088] Thickness.—Medium. program. [0105] The present neW variety of Myrobalan tree, its [0089] Texture.—Medium. ?oWers, foliage and fruit herein described may vary in slight [0090] Bl00m.—Moderate. detail due to climate, soil conditions and cultural practices under Which the variety may be groWn. The present descrip [0091] Tendency t0 crack.—Slight in Wet Weather. tion is that of the variety groWn under the ecological [0092] Tenacity.—Tenacious to ?esh. conditions prevailing near Modesto, Calif. [0093] Stone: 1. A neW and distinct variety of myrobalan (Prunus cerasifera) tree, substantially as illustrated and described, [0094] Type.—Clingstone. characteriZed by being medium to large in siZe, moderately [0095] Size.—Small. Average length 35/64 inch vigorous, upright groWth and having graft compatibility With numerous rootstocks and also With various cherry trees, Average(13.9 thickness—17/64Average Width inch 25/64 (6.8 inch (9.9 giving this myrobalan tree the potential to be used as an interstock for groWing cherries on various non-compatible [0096] F0rm.—Ovoid. rootstocks; the neW variety is further characteriZed by hav [0097] Base. —Usually round. Varies from rounded ing the ability to reduce the siZe of the cherry tree by to straight. shortening the length of the interstock betWeen the cherry [0098] Apex.—Acuminate. Length—short, 1/16 scion and the rootstock: inch (1.6 * * * * * Plant Patent Application Publication Sep. 26, 2002 US 2002/0138884 P1