Strawberry plant named ‘Fronteras’

Abstract

‘Fronteras’ is a short-day (June bearing) cultivar similar to ‘Camarosa’ (U.S. Plant Pat. No. 8,708), but with greater productivity, higher quality fruit, and earlier production; it is similar to ‘Ventana’ (U.S. Plant Pat. No. 13,469) and ‘Benicia’ (U.S. Plant Pat. No. 22,542), but with somewhat later production, a larger plant, larger fruit size, and higher quality fruit.

Description

Genus and species: The strawberry cultivar of this invention is botanically identified as Fragaria×ananassa Duch.

Variety denomination: The variety denomination is ‘Fronteras’.

BACKGROUND OF THE INVENTION

This invention relates to a new and distinctive short-day type cultivar designated as ‘Fronteras’, which resulted from a cross performed in 2008 between two unreleased germplasm accessions Cal 4.18-4 and Cal 5.165-1. Accession Cal 4.18-4 was chosen as a parent due to its very high early productivity, large and high quality fruit, and moderate plant vigor. Accession Cal 5.165-1 was chosen as a parent due to its vigorous but open plant habit and firm, large and flavorful fruit, and extended productivity.

‘Fronteras’ was first fruited near Irvine, Calif. in 2009, where it was selected, originally designated Cal 8.132-608, and propagated asexually by runners. Following selection and during testing the plant of this selection was designated ‘C235’. With the decision that this plant was to be released, this plant was given the name ‘Fronteras’ for purposes of introduction into commerce and for international registration and recognition. Asexual propagules from this original source have been tested in Watsonville Calif. and near Irvine, Calif., and to a limited extent in grower fields starting in 2010. The cultivar is stable and reproduces true to type in successive generations of asexual reproduction.

BRIEF SUMMARY OF THE INVENTION

‘Fronteras’ is a short-day (June bearing) cultivar similar to ‘Camarosa’ (U.S. Plant Pat. No. 8,708), but with greater productivity, higher quality fruit, and earlier production; it is similar to ‘Ventana’ (U.S. Plant Pat. No. 13,469) and ‘Benicia’ (U.S. Plant Pat. No. 22,542), but with somewhat later production, a larger plant, larger fruit size, and higher quality fruit.

BRIEF DESCRIPTION OF THE DRAWINGS

The Figures depict various characteristics of the ‘Fronteras’ cultivar.

FIG. 1 shows the general flowering and fruiting characteristics of the plant in a field planting.

FIG. 2 shows a typical leaf at mid-season.

FIG. 3 shows representative mid-season fruit.

DETAILED DESCRIPTION OF THE INVENTION

‘Fronteras’ is typical of short-day strawberry cultivars and produces fruit over an extended period when treated appropriately in arid, subtropical climates. The production pattern for ‘Fronteras’ is similar to that for ‘Camarosa’ (U.S. Plant Pat. No. 8,708), although it is slightly earlier to initiate fruiting with most cultural treatments. ‘Fronteras’ initiates fruiting slightly later than ‘Ventana’ (U.S. Plant Pat. No. 13,469) and ‘Benicia’ (U.S. Plant Pat. No. 22,542) when established in very early fall. Fruit from Fronteras is larger and darker than fruit from unreleased parent variety Cal 4.18-4. Fruit from Fronteras is larger, more evenly colored, and more conical than fruit from unreleased parent variety Cal 5.165-1. The plant for Fronteras is much larger than for either parent, and Fronteras produces fruit earlier in the season than Cal 5.165-1. ‘Fronteras’ will be of special interest for winter plantings, where ‘Camarosa’, ‘Ventana’, and ‘Benicia’ have been successful, and in summer plantings where ‘Chandler’ (U.S. Plant Pat. No. 5,262) and ‘Camino Real’ (U.S. Plant Pat. No. 13,079) have been successful.

Plants and Foliage:

Fruiting plants of ‘Fronteras’ are slightly taller, more erect, and more open than all of the comparison cultivars in most production environments. Comparative statistics for foliar characters near mid-season are given for ‘Fronteras’ and three comparison cultivars in Table 1. Individual leaflets for ‘Fronteras’ are to those of the comparison cultivars, and are more elongated than for ‘Benicia’. The leaflet base is obtuse and the leaflet margin is serrate to crenate. Leaves (including petioles) for ‘Fronteras’ are slightly longer than for ‘Ventana’ and ‘Camarosa’, shorter than for ‘Benicia’. Petioles for ‘Fronteras’ are generally longer than those of ‘Ventana’, ‘Benicia’ and ‘Camarosa’. The adaxial (upper) and abaxial (lower) surfaces of leaves for ‘Fronteras’ are lighter than for ‘Camarosa’ and ‘Benicia’, darker and less yellow than for ‘Ventana’ leaves at midseason. Leaves of ‘Fronteras’ have similar concavity to ‘Camarosa’, and are less concave those for ‘Ventana’. Serrations at midseason are less pointed than for ‘Ventana’, similar in shape and number to ‘Benicia’ and ‘Camarosa’. The stipule length is somewhat longer for ‘Fronteras’ than for the comparison cultivars.

TABLE 1
Foliar and plant characteristics for
‘Fronteras’, ‘Camarosa’, ‘Ventana’, and ‘Benicia’.
	Cultivar
Foliar Character	‘Camarosa’	‘Ventana’	‘Benicia’	‘Fronteras’
Plant height (mm)
mean	227	277	245	313
range	190-320	250-300	220-260	300-330
Plant spread (mm)
mean	368	425	414	421
range	300-465	375-525	360-500	345-485
Mid-tier leaflet
Length (mm)
mean	85	89	80	83
range	70-95	80-110	70-90	80-90
Width (mm)
mean	79	77	80	73
range	65-90	70-90	75-80	60-90
Mid-tier leaf
Length (mm)
mean	230	231	264	247
range	200-290	180-260	220-310	200-280
Width (mm)
mean	143	153	161	141
range	120-170	140-160	150-180	120-160
Leaf components
Petiole length
(mm)
mean	110	113	136	141
range	90-150	80-120	110-160	110-160
Petiole diameter
(mm)
mean	3.6	5.3	4.9	4.6
range	3-4	4-7	4-6	4-5
Petiolule length
(mm)
mean	5.1	6.9	5.3	5.7
range	4-6	6-8	4-6	4-7
# leaflets/leaf	3	3	3, rarely 4 or	3
			5
Leaf convexity	most flat to	flat to very	flat to	flat to
	slight	concave	concave	concave
	concave
Serrations
number/leaf	20.8	20.6	20.5	20.1
range	19-23	18-25	18-23	18-22
shape	semi-	semi-	round to	round to
	pointed	pointed	semi-	semi-
			pointed	pointed
Leaf pubescence	light-	moderate-	moderate-	moderate
	moderate	heavy	light
Petiole pubescence
density	heavy	moderate-	heavy	moderate-
	heavy		heavy
direction	perpen-	perpen-	perpen-	perpen-
	dicular to	dicular	dicular to	dicular
	acropetal		acropetal
Petiole color	2.5 GY 8/9	7.5 GY 9/4	7.5 GY 8/10	2.5 GY 7/10
(Munsell)
Stipule length
(mm)
mean	27.2	24.0	31.1	37.5
range	20-34	20-30	25-40	30-40
Stipule color
(Munsell)
core	2.5 Y 6/8	2.5 GY 8/9	2.5 Y 9/4	7.5 GY 8/7
margins	7.5 Y 6/7	5 GY 8/8	5 GY 8/8	5 GY 8/8
Stolon base	11.7	15.2	16.5	13.2
diameter (mm)
Stolons per	22.7	18.8	22.9	23.0
nursery mother
plant
Venation	pinnate	pinnate	pinnate	pinnate
pattern
color (Munsell)	7.5 GY 8/7	7.5 GY 9/4	7.5 GY 8/7	2.5 GY 9/8

Disease and Pest Reaction:

‘Fronteras’ is moderately resistant to powdery mildew (Sphaerotheca macularis), moderately susceptible to Anthracnose crown rot (Colletotrichum acutatum), and moderately resistant to Verticillium wilt (Verticillium dahliae), Phytophthora crown rot (Phytophthora cactorum) and common leaf spot (Ramularia tulasnei) (Table 2). When treated properly, it has tolerance to two-spotted spider mites (Tetranychus urticae) equal to that for the comparison cultivars. ‘Fronteras’ is tolerant to strawberry viruses encountered in California.

TABLE 2
Disease resistance scores for ‘Fronteras’ and three comparison cultivars;
all scores were obtained in evaluations conducted in 2012-2013.
	Phytophthora	Verticillium	Colletotrichum
	Resistance Score	Resistance Score	Resistance Score
Genotype	(5 = best)	(5 = best)	(5 = best)
‘Camarosa’	3.6	2.8	7.3
‘Ventana’	2.1	2.9	3.0
‘Benicia’	3.5	1.6	2.5
‘Fronteras’	4.1	3.7	2.5

Flowering, Fruiting, Fruit, and Production Characteristics:

‘Fronteras’ is similar to other California short-day strawberry cultivars (e. g. ‘Ventana’, ‘Camarosa’, and ‘Benicia’) in that it will flower over an extended period and into spring or summer, given appropriate local temperature and horticultural conditions. With most planting treatments ‘Fronteras’ produces fruit slightly later than ‘Ventana’ and ‘Benicia’ and earlier than for ‘Camarosa’. Comparative statistics for flower and fruit characters near mid-season are given for the four cultivars in Table 4. The primary flowers for ‘Fronteras’ are slightly larger than for ‘Camarosa’ but smaller than ‘Ventana’ and ‘Benicia’ with a calyx that is distinctly larger than the corolla on primary fruit. The calyx for ‘Fronteras’ varies in position but frequently has a slight indent early in the season and is even with the fruit later in the season; each primary flower has 5-7 petals, similar to the comparison cultivars on average. The fruit shape for ‘Fronteras’ is consistent throughout the season, and is typically medium to long conic, with a tendency to be somewhat cylindrical and blunt. It is easily distinguished by fruit shape from ‘Camarosa’ (shortened and flattened conic), or ‘Ventana’ (medium symmetrical conic), and ‘Benicia’ (often flattened). Fruit size for ‘Fronteras’ is substantially larger than for the comparison cultivars. External fruit color for ‘Fronteras’ is similar to that for ‘Camarosa’, lighter than for ‘Benicia’, and darker than for ‘Ventana’; internal color for ‘Fronteras’ is somewhat lighter than for the comparison cultivars (Table 3). Achenes vary from yellow to dark red, and are even with the fruit surface or slightly indented.

TABLE 3
Foliar and fruit color characteristics for ‘Fronteras’ and
three comparison cultivars.
	Cultivar
Color Character	‘Camarosa’	‘Ventana’	‘Benicia	‘Fronteras’
Leaf color
(CIELAB)
Adaxial
L*
mean	38.3	39.2	35.0	38.3
range	37.3-39.8	36.0-41.1	33.3-36.4	34.8-41.1
a*
mean	−12.2	−14.3	−11.7	−13.0
range	−9.5-−15.5	−12.9-−16.7	−10.3-−13.5	−11.3-−15.6
b*
mean	16.9	20.6	16.9	18.7
range	13.3-19.9	17.3-24.8	13.1-21.7	13.8-22.6
Munsell	5 GY 5/5	2.5 GY 6/8	5 GY 5/6	5 GY 4/3
Abaxial
L*
mean	52.5	53.2	48.5	48.9
range	51.3-54.6	51.8-54.6	41.7-52.3	40.2-51.2
a*
mean	−13.1	−14.2	−13.5	−14.1
range	−11.4-−14.9	−13.9-−14.7	−11.9-−16.8	−13.0 −15.1
b*
mean	20.5	21.7	20.0	21.4
range	18.9-22.4	20.3-23.3	17.9-21.9	20.0-21.9
Munsell	7.5 GY 8/7	10 GY 8/7	7.5 GY 5/7	10 GY 7/8
Fruit color
(CIELAB)
External
L*
mean	38.6	38.1	36.0	36.9
range	34.7-42.7	37.6-39.0	34.2-37.5	35.5-37.3
a*
mean	34.4	33.4	31.2	37.3
range	33.6-36.2	29.4-38.7	26.6-36.3	35.1-39.9
b*
mean	22.5	19.2	14.2	19.2
range	18.8-29.3	17.8-21.1	10.6-17.3	16.7-19.0
Munsell	7.5 R 4/11	5 R 4/12	2.5 R 4/0	7.5 R 4/11
Internal
L*
mean	50.2	48.6	44.0	55.7
range	46.6-53.3	46.2-52.3	40.8-47.0	50.4-60.4
a*
mean	30.8	28.9	30.9	20.9
range	25.6-35.4	23.5-33.0	27.8-33.6	18.1-25.9
b*
mean	30.1	31.3	27.5	25.4
range	28.0-32.0	30.6-32.5	24.6-28.8	19.6-30.7
Munsell	7.5 R 5/13	7.5 R 6/13	5 R 4/2	7.5 R 5/3
Achene color	2.5 Y 7/10	10 Y 8/11	5 R3/7	2.5 R 8/12
Munsell

TABLE 4
Flower and fruit characters for ‘Fronteras’ and three comparison cultivars.
	Cultivar
Character	‘Camarosa’	‘Ventana’	‘Benicia	‘Fronteras’
Petal number
mean	5.8	6.2	6.1	5.9
range	5-7	5-7	5-7	5-7
Petal shape
apex	truncate to	truncate to	truncate to	truncate to
	slightly	slightly	slightly	slightly
base	obtuse	obtuse	obtuse	obtuse
margin	attenuate	attenuate	attenuate	attenuate
	entire	entire	entire	entire
Petal length
(mm)
mean	11.5	13.3	11.7	13.5
range	10-13	11-15	8-13	13-15
Petal width (mm)
mean	12.0	14.6	14.4	12.6
range	10-14	13-16	8-13	8-14
Flower position	most even	even to	even to	most even
(relative to	some	exposed	exposed	some
foliage)	exposed			interior
Calyx diam.
(mm)
mean	40.4	47.0	50.8	48.3
range	33-47	40-50	47-53	44-54
Corolla diam.
(mm)
mean	26.1	39.0	39.6	31.3
range	23-31	35-45	39-41	29-38
Sepal length
(mm)
mean	14.3	16.6	16.4	14.6
range	12-18	14-19	13-20	11-17
Sepal width
(mm)
mean	8.3	8.4	8.4	9.3
range	7-10	7-10	7-10	7-11
Sepal color	5 GY 7/10	5 GY 5/5	10 GY 8/7	5 GY 5/6
(Munsell)
Pedicel length
(mm)
mean	155	115	183	125
range	130-180	90-140	150-210	90-170
Pedicel diameter
(mm)
mean	2.7	3.5	3.7	4.7
range	2-4	3-4	3-5	4-6
Pedicel color	7.5 GY 8/7	5 GY 8/9	2.5 GY 8/9	7.5 GY 6/8
Fruit shape
Fruit length
(mm)
mean	46.0	48.4	46.5	54.5
range	40-48	47-52	41-52	51-58
Fruit width (mm)
mean	37.4	42.6	42.4	46.7
range	33-46	40-46	36-46	42-54
Length/width
ratio	1.26	1.17	1.08	1.15
range	1.0-1.4	1.1-1.2	1.0-1.2	1.0-1.2
subjective	Obovate-	Medium	Medium	Medium-
	flat	conic	conic	long conic
Primary/
secondary
fruit comparison
size (subjective)	50-70%	55-75%	55-65%	60-80%
shape	similar	similar	similar	similar
	shape, more	shape	shape	shape
	conic
Extent/size of	small-	small	small-absent	small-absent
hollow core	absent
Calyx
position	indented-	indent-	even-	Indented-
	neck	reflexed	indented	even
size relative to	equal or less	equal or less	equal or	equal or less
fruit	than fruit	than fruit	greater than	than fruit
	diameter	diameter	fruit	diameter
			diameter
Seed position	indented-	mostly even	even-	indented-
	extruded		indented	extruded
Adherence of	weak	intermediate	weak	intermediate
Calyx to Fruit
Flower and plant measurements obtained on April, 2012, fruit measurements May 10-20, 2012.

‘Fronteras’ has been tested under a variety of cultural regimes, and optimal performance is obtained when nursery treatments and nutritional programs similar to those for ‘Camarosa’, ‘Ventana’, and ‘Benicia’ are used. In general, plants of ‘Fronteras’ are greater in vigor than the comparison cultivars with very early season planting. ‘Fronteras’ retains excellent fruit quality in summer planting systems.

When treated with appropriate planting regimes, ‘Fronteras’ has substantially larger sized fruit and produces individual-plant yields greater than any of the comparison cultivars (Table 5). Commercial appearance ratings have also been substantially better than those for all of the comparison cultivars, especially in comparison with ‘Camarosa’. Fruit for ‘Fronteras’ is similar in firmness to fruit from ‘Ventana’, less firm than the other comparison cultivars. Subjectively, ‘Fronteras’ has excellent flavor. The fruit will be exceptional for both fresh market and processing, and will be useful for home garden purposes.

TABLE 5
‘Fronteras’ and three comparison cultivars evaluated near Watsonville,
CA in 2010-12. All plants for these trials were harvested from a
commercial nursery near Macdoel, CA on October 15-16, and
transplanted after 6-7 days supplemental storage. Fruit harvest was
initiated in early April and continued through the last week of August.
(52″ 2-row beds, 17,300 plants/acre).
		Appearance	Fruit
	Yield	Score	Size
Item	(g/plant)	(5 = best)	(g/fruit)	Firmness
‘Camarosa’	1,815	2.8	27.1	11.6
‘Ventana’	2,080	3.3	30.1	10.2
‘Benicia’	1,649	3.4	33.1	11.1
‘Fronteras’	2,793	4.2	35.1	11.1

Claims

1. A new and distinct cultivar of strawberry plant having the characteristics substantially as described and illustrated herein.