An ananassa type strawberry plant characterized by its high productivity and high disease resistance. The cultivar is suited for propagation in the field and produces slightly tart fruit which is acceptable for the fresh market.
Description
BACKGROUND OF THE INVENTION The present invention includes a new and distinct cultivar of Fragaria ananassa known by the varietal name `Mira`, originally designated as "K84-5". The new variety resulted from a cross performed in 1982 between the unpatented cultivars `Scott` and `Honeoye`. The new variety first fruited at the Robinsons Corner research field of the Atlantic Food and Horticultural Research Centre, Agriculture and Agri-Food Canada in Chester Basin, Nova Scotia, Canada in 1984. The new variety was first asexually reproduced by runners in 1985 at the Atlantic Food and Horticultural Research station in Kentville, Nova Scotia, Canada. Since 1992, propagules of the new variety have been tested at the Agriculture and Agri-Food Canada research centers in Charlottetown, Prince Edward Island, Buctouche, New Brunswick and Fredericton, New Brunswick, all of Canada and at the Newfoundland Department of Agriculture field site at Pynn's Brook, Newfoundland, Canada and has been found to retain its distinctive characteristics through successive propagation. The new variety is typical of short-day varieties and produces fruit over a four week period in northern temperate climates. `Mira` ripens in the mid-late season, and the pattern of production is similar to the standard variety `Kent` but three to five days later. `Mira` has a yield substantially greater than the varieties `Annapolis` (unpatented), `Cavendish` (the subject of U.S. Application Ser. No. 08/535,610, filed Sep. 8, 1995), `Blomidon` (unpatented), and `Bounty` (unpatented) and a yield equal to `Kent` (unpatented). The appearance of `Mira` is superior to `Kent` because of improvements in the uniformity of `Mira's` fruit shape and, unlike `Kent`, the fruit color of `Mira` does not darken excessively when over-ripe or after storage.
DESCRIPTION OF THE DRAWINGS The accompanying photographic drawing illustrates the characteristic fruit and foliage of the new variety `Mira`, with the color being as nearly true as possible with color illustrations of this type.
DESCRIPTION OF THE PLANT The following detailed description sets forth the characteristics of the new cultivar. Color references are made to The R.H.S. Colour Chart of The Royal Horticultural Society of London and were also determined using a Minolta Colorimeter. Classification: The new variety is botanically classified as Fragaria ananassa and commercially classified as a short-day strawberry. Plant and foliage: When propagated in the nursery, `Mira` has similar runner production to the unpatented variety `Honeoye` but produces more runners than `Kent`. The leaf color of `Mira` and `Kent` are medium green while `Honeoye` leaves are darker green. Comparative statistics for foliar characteristics, including leaflet measurements, serration description, and petiole pubescence are given in Table 1. Individual central (terminal) leaflets of `Mira` are slightly longer and more narrow than those of `Kent` and `Honeoye`. Hence, the leaflet shape of `Mira` is more ovate and less rounded than those of `Kent` and `Honeoye`. The leaflet serrations of `Mira` and `Kent` are semi-pointed whereas they are more rounded for `Honeoye`. The serration at the tip of the central leaflet is small for `Honeoye` but medium in size for `Mira` and `Kent`. The leaf and petiole pubescence for `Mira`, `Kent`, and `Honeoye` are similar with the exception that `Honeoye` has more hairs on the leaflets. TABLE 1______________________________________Foliar characteristics for`Mira`, `Kent`, and `Honeoye` CultivarFoliar Character `Mira` `Kent` `Honeoye`______________________________________Central leafletLength (mm)mean 84.2 82.5 83.8range 68-100 72-100 65-97Width (mm)mean 68.4 72.3 70.3range 56-85 60-87 55-87Length/width ratio 1.23 1.14 1.19Truss length (cm) 28.9 30.6No. leaflets/leaf 3 3 3Leaf convexity flat flat flatSerrationsNumber moderate moderate manyShape semi-pointed semi-pointed semi-roundTip serration size medium medium smallLeaf pubescence sparse sparse mediumPetiole pubescenceDensity sparse sparse sparseDirection perpendicular perpendicular perpendicularLeaf ColorUpper surface Green Group Green Group 137A-137B 137ALower surface Green Group Green Group 138B 138B______________________________________ Blooming characteristics: The length of bloom for `Mira` and `Kent` is about three weeks when grown in Kentville, Nova Scotia, Canada in a matted row cultural system. Flowering for both `Mira` and `Kent` typically begins on June 1 and ends on June 21 of each year. Disease resistance: `Mira` has a much higher level of resistance to red stele root rot (Phytophthora fragariae) than `Kent` and `Honeoye` and these varieties' reaction to distinct races of the pathogen are given in Table 2. `Mira` is resistant to race A-1, A-2, and A-3 while `Kent` and `Honeoye` are susceptible to these races. `Mira` and `Kent` are moderately resistant to powdery mildew (Sphaerotheca macularis) but `Honeoye` is susceptible. `Mira` and `Honeoye` are moderately resistant to leaf scorch (Diplocarpon earliana) and common leaf spot (Mycosphaerella fragariae) but `Kent` is susceptible to both. `Kent` and `Honeoye` are resistant to green petal phytoplasma and `Mira` is moderately resistant. `Mira` and `Honeoye` are less affected by fruit rot (Botrytis cinerea) than `Kent`. TABLE 2______________________________________Resistance of `Mira`, `Kent`, and `Honeoye`to races of Phytophthora fragariae (red stele root rot).CultivarRace `Mira` `Kent` `Honeoye`______________________________________A-1 R S SA-2 R S SA-3 R S SA-4 R S or I SA-5 S S SA-6 MR S or I SA-7 S S S______________________________________ S = susceptible; I = intermediate; MR = moderately resistant; R = resistant Genetic fingerprinting of leaf extracts: Random Amplified Polymorphic DNA banding patterns with primers UBC59, UBC76, UBC85, UBC100 and UBC287 (all available from the University of British Columbia, Nucleic Acid-Protein Service Unit) distinguished `Mira` from seven other strawberry varieties including `Scott` and `Honeoye`, the parents of `Mira` as shown in Table 3. The banding pattern of `Mira` with primers UBC59, UBC85, and UBC100 was distinct from the other varieties. The primer UBC100 produced a distinct pattern for all eight varieties. This testing was done in the Biotechnology Laboratory of the Atlantic Food and Horticultural Research Centre following the techniques of Levi et al., Identification of Strawberry Genotypes and Evaluation of their Genetic Relationships Using Randomly Amplified Polymorphic DNA (RAPD) Analysis, Adv. In Strawberry Research, 13:36-39 (1994). TABLE 3______________________________________Genetic fingerprinting of `Mira` and seven otherstrawberry varieties by Random Amplified PolymorphicDNA. Bands from reliable polymorphic RAPD fragmentsfrom three replications are represented as 0 = absent or 1 = present.PrimerUBC59 UBC76 UBC85 UBC100 UBC287Band Number for each primer and DNA patternVariety 12345 123 123 12345 123______________________________________Mira 00111 a 100 a 111 a 00111 a 010 aScott 10010 b 100 a 100 b 00010 b 010 aHoneoye 10011 c 000 b 010 c 10100 c 011 bTotem 10001 d 100 a 000 d 11110 d 101 cAnnapolis 01111 e 101 c 010 c 11101 e 011 bCavendish 11011 f 101 c 000 d 11100 f 111 dBlomidon 11111 g 101 c 010 c 11010 g 011 bKent 11111 g 100 a 011 e 10110 h 011 b______________________________________ Flower and fruit production characteristics: Comparative statistics for flower and fruit characteristics near mid-season, including fruit color, are given for the three cultivars in Table 4. Flowers of `Mira` and `Honeoye` are positioned even with the foliar canopy but flowers of `Kent` are above the canopy. Flowers of `Mira` and `Kent` are medium in size and smaller than for `Honeoye`. Calyx size, as measured with a leaf area meter, is smaller for `Mira` and `Kent` than for `Honeoye`. The calyx coloration of `Mira` is medium green. The position of the calyx on a raised neck for `Mira` is in contrast to the other two varieties which have a position even with the top of the berry. `Mira` berries pick with a much longer stem than for `Kent` and `Honeoye`. The fruit shape of `Mira` is conic comparted to short-conic for `Honeoye` and ovoid for `Kent`, as confirmed by the length/width ratios. The seeds of `Mira` are more deeply indented than those of the other two varieties. Berries of all three varieties are moderately firm but `Mira` has tougher skin. The exterior fruit color of `Mira` and `Kent` is more toward orange while `Honeoye` is more toward purple as reflected in hue angle. `Mira` has a lighter interior than the other two varieties. The flesh coloration of `Mira` is about RHS 41 A, becoming progressively lighter in coloration towards the core. After a 7 day period of storage, the exterior hue angle changed -6% for `Mira`, -28% for `Kent`, and -17% for `Honeoye` indicating that `Mira` holds its color well in storage while the other varieties darken. TABLE 4______________________________________Flower and fruit charcateristics for`Mira`, `Kent`, and `Honeoye` CultivarCharacter `Mira` `Kent` `Honeoye`______________________________________Flower position even above even(relative to leaf canopy)Flower truss length medium-long medium-long short- mediumNumber of flowers per truss 11.1 11.2(average)Flower size (diameter) medium medium medium- (32.7 mm) (32.4 mm) largeFlower color white whitePetal spacing touching overlapping touchingCalyx area (cm.sup.2) 3.8 3.9 6.3Calyx position raised neck even evenFruit stem length very long medium mediumFruit shapelength/width ratio 1.00 0.76 0.97subjective conic ovoid short- conicSeed position indent even slight indentFruit firmness (N) 4.6 4.8 5.2Skin toughness (g) 15.3 6.2 9.2Color (R.H.S. Colour CHart)Fruit exterior Red Group Red Group 42A 46AFruit interior Red Group Red Group 44B 41AColor (Minolta Colorimeter)Fruit exteriorhue angle 27.9 29.1 24.8chroma 45.9 38.9 37.8lightness 36.2 37.1 32.3Fruit interiorhue angle 50.2 47.3 44.2chroma 23.8 28.1 34.6lightness 63.0 55.0 56.1______________________________________ Production characteristics: `Mira` has been widely tested for several years. As shown in Table 5, `Mira` typically yields equal to `Kent` (the high yield standard variety in the trials). The percent of fruit classified as unmarketable is typically lower for `Mira` than `Kent` due to the greater resistance of `Mira` to Botrytis fruit rot. The fruit of `Mira` are slightly smaller (by weight) than `Kent` and the season of harvest is consistently later than `Kent`. Subjectively, `Mira` has a flavor similar to `Kent`, but more tart. `Mira` fruit will be acceptable for the fresh market and attractive to growers because of high productivity and disease resistance. `Mira` produces abundant runners in the nursery and is readily propagated by conventional field techniques. TABLE 5______________________________________Performance of `Mira` and `Kent` for 1993, 1994, 1995, and 1996averaged over four sites: Kentville, NS; Charlottetown, PEI;Boctouche, NB; and Pynn's Brook Nfld. Plants were grown in mattedrows and three blocks of 3 m long rows were harvested at each site.Total Yield % yield SIze Mean harvest(t/ha) unmarketable (g/fruit) (day of year)______________________________________1993`Mira` 19.3 6.2 13.7 208.1`Kent` 21.1 9.0 14.5 205.71994`Mira` 24.7 14.2 12.0 199.9`Kent` 25.0 18.8 12.3 198.81995`Mira` 23.8 8.0 13.4 199.0`Kent` 21.5 10.2 13.9 197.01996`Mira` 16.1 11.8 9.8 198.3`Kent` 19.3 11.4 10.4 197.3______________________________________
Claims
1. A new and distinct variety of strawberry plant substantially as shown and described.