Kiwi plant named ‘AU Fitzgerald’

Abstract

A new and distinct cultivar of the species Actinidia deliciosa A. Chev. is described. The parentage of this new cultivar is unknown, but it is most likely an open pollinated ‘Haywood’ as it was grown from seed collected from fruit purchased in a grocery store. The new cultivar is distinguished by a lower chilling requirement and higher yields, smaller fruit with a greater length times diameter ratio, and the fruit has a lower pH and higher titratable acidity, % soluble solids, % dry matter, reducing and total sugars, total and reduced form of ascorbic acid (Vitamin C), Vitamin C antioxidant capacity and cellular capacity to reduce free radicals is higher, lower levels of β-carotene, higher chlorophyll levels (a and b), lower phenolic content and higher flavonoid content than the comparison cultivar ‘Hayward’ in Alabama.

Description

RELATED APPLICATIONS

U.S. patent application Ser. No. 12/150,857, filed on April 30, 2008, and entitled “Kiwi plant named ‘AU Authur’” is incorporated by reference herein.

Latin name of the genus and species of the plant claimed: Actinidia deliciosa A. Chev.

Variety denomination: ‘AU FITZGERALD’.

BACKGROUND OF THE INVENTION

‘Hayward’ is the most commercialized female kiwi cultivar grown and marketed in the world. The ‘Hayward’ cultivar is produced commercially in California in the U.S. and in New Zealand, and is the kiwi fruit most often found in U.S. grocery stores. Attributes of the ‘Hayward’ cultivar that have led to its dominance of the kiwi market in the past are its distinctive green flesh, good flavor and long storage life. It is not known what male cultivar was used to pollinate the female flowers that produced the fruit and seed that resulted in the new cultivar. ‘Matua’ and ‘Tomuri’ are two male cultivars frequently used.

Both the ‘Hayward’ cultivar and the present invention are deciduous vines of Actinidia deliciosa A. Chev. The Actinidia deliciosa species originated in China and parts of Asia and is known as the Chinese gooseberry. Plant material of this species was taken to New Zealand where new cultivars such as ‘Hayward’ were developed. Due to the appearance of the fruit of the Chinese gooseberry, it was given the name kiwi fruit in New Zealand after the native kiwi bird.

Many plantings of the ‘Hayward’ cultivar were established in Alabama as well as the adjoining southeastern states. These plantings were established near the coast in most cases. The vines grew vigorously but were unfruitful. In Alabama, research plantings were established in different locations that varied from the coast to the center of the state. The location that the kiwi have been most productive is in the center of the state in Chilton County where the commercial peach industry is located. The ‘Hayward’ cultivar has not been productive there.

Research has shown that the ‘Hayward’ cultivar requires at least 900 hours of chilling for sufficient vegetative budbreak and flower development and that 1150 hours chilling is required for maximum flowering. From chilling requirement research, flower abortion decreased as chilling hours received increased for all cultivars.

SUMMARY OF THE INVENTION

Mrs. A. A. Fitzgerald of Summerdale, Ala. purchased kiwi fruit from a local grocery store and planted some seeds from the fruit. She ended up with one female and one male plant that bloomed together, were very productive and matured a crop of quality fruit. The fruit purchased was probably from the ‘Hayward’ cultivar.

The present invention relates to a new and distinctive kiwi cultivar having a generally cylindrical shaped fruit that has brown skin covered with medium length brown hairs that strongly adhere to the skin surface. The pericarp of the fruit is green.

In the climate of central Alabama, vegetative bud break occurs during the last two weeks of March and the bloom period occurs during the last week of April and the first two weeks of May, depending on the climate during the season. The fruit reaches a minimum percent soluble solids level of 6.5 in central Alabama by mid-October.

The seed from which ‘AU Fitzgerald’ originated from was originally planted at Summerdale, Ala., near the Gulf Coast in Baldwin County. It was very fruitful at its original location indicating it has a lower chilling requirement than the ‘Hayward’. ‘AU Fitzgerald’retained a statistically greater number of flowers than ‘Hayward’ at 700, 800 and 1000 chilling hours received. The data indicates that ‘AU Fitzgerald’ has a lower chilling requirement than ‘Hayward’, which explains the greater fruit set and yield of ‘AU Fitzgerald’ compared to ‘Hayward’ in Alabama.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a photograph of hanging fruit of the ‘AU Fitzgerald’ cultivar.

FIG. 2 is a photograph of vines with fruit of the ‘AU Fitzgerald’ cultivar.

FIG. 3 is a photograph of fruit of the ‘AU Fitzgerald’ cultivar and the ‘Hayward’ cultivar.

DETAILED BOTANICAL DESCRIPTION

The new cultivar ‘AU Fitzgerald’ is pistillate, with imperfect flowers, e.g. the flowers produce only sterile pollen and thus require a pollinizer for fruit production. Two A. deliciosa pollinizers, ‘Matua’ and ‘AU Authur’ have been used to pollinize ‘AU Fitzgerald’.

The new cultivar is able to be asexually reproduced by softwood and hardwood cuttings or by grafting or budding on to a seedling or cutting grown rootstock. The new cultivar was asexually reproduced at the Chilton Area Research and Extension Center at Clanton, Ala., US. The instant plant was grafted on a rootstock named Bruno. The unique characteristics come true to form and are established and transmitted through succeeding asexual propagations.

The distinctive characteristics of this new kiwi cultivar described in detail below have been observed in a replicated field experiment at the Chilton Area Research and Extension Center at Clanton, Ala., US. The plants were one year old rooted cuttings when planted. The ‘Hayward’ cultivar was evaluated in the same replicated field experiment and was used as the standard cultivar for comparison.

Both the ‘AU Fitzgerald’ and ‘Hayward’ have a fruit shape in cross section that is generally cylindrical. However, the ‘AU Fitzgerald’ fruit is oblong to slightly ovate, whereas the ‘Hayward’ fruit is more broad elliptic to oblong. ‘AU Fitzgerald’ has a greater fruit length to diameter ratio. The shoulder on the stalk end of the fruit of each cultivar is rounded and flat and the stylar end of the fruit is flat and flush. The cultivars do not differ in flesh or skin color as measured by the Minolta calorimeter and The Royal Horticulture Society's Colour Chart (2001); however, higher chlorophyll a and b content were measured in ‘AU Fitzgerald’ and higher β-carotene content was measured in ‘Hayward’.

‘AU Fitzgerald’ has a lower chilling requirement, smaller fruit size, greater fruit length to diameter ratio, greater fruit set and crop load, and the fruit has a lower pH and higher titratable acidity, % soluble solids, % dry matter, reducing and total sugars, total and reduced form of ascorbic acid (Vitamin C), Vitamin C antioxidant capacity and cellular capacity to reduce free radicals is higher, lower levels of β-carotene, higher chlorophyll levels (a and b), lower phenolic content and higher flavonoid content than the comparison cultivar ‘Hayward’ in Alabama.

The table below illustrates the specific differences between the ‘AU Fitzgerald’ cultivar and the ‘Hayward’ cultivar.

TABLE I
Comparison of ‘AU Fitzgerald’ and ‘Hayward’ cultivars.
	‘AU Fitzgerald’	‘Hayward’
Plant
Plant: sex expression	female (flowers
	imperfect)
Plant: ploidy	hexaploid
Plant: vigor	medium
Young shoot: hairs	present
Young shoot:	medium
density of hairs
Young shoot:	short	hirsute
type of hairs
Young shoot:	medium
anthocyanin
coloration of
growing tip
Young shoot:	absent
anthocyanin
coloration of
leaf axil
Plant: average	plant is a vine trained
height and spread	to grow on a trellis sys-
	tem. In the T-bar system
	rows are spaced 16 feet
	apart and plants are
	planted 8 feet apart in the
	row. The trellis is 6 feet
	wide. The vines are very
	vigorous and will cover
	the trellis by the end
	of the second year. To
	maintain and control
	the plant, the vines
	are pruned in the dor-
	mant season and several
	times during the growing
	season.
Stem
Stem: coloration	weak
of leaf axil
Stem: diameter	medium
Stem base diameter	mean 16.7 mm	mean 14.8 mm
	(range 15.6-18.7 mm)	(range 14.6-15.1
		mm)
Stem mid section	mean 11.5 mm	mean 10.4 mm
diameter	(range 11.3-11.8 mm)	(range 9.3-11.6
		mm)
Stem: dormant bud	7.4 mm (6.4-9.2 mm)	7.71 mm (7.1-9.1
diameter		mm)
Stem: color on upper	dark brown (N199B)	dark brown (200B)
side of shoot
Stem: character	smooth
of bark
Stem: hairs	present
Stem: conspicuous-	conspicuous
ness of lenticels
Stem: number of	medium (258/sq cm)	medium (239/sq cm)
lenticels	range (200-323/sq cm)	range (181-329/sq
		cm)
Stem: color of lenticels	brownish-white
Stem: size of bud support	medium
Stem: visibility of bud	almost buried
(dormant canes)
Stem: number of	medium
hairs visible on
bud (dormant canes)
Stem: leaf scar	length (mm) - 4.8
	(range 3.8-5.4)
	width (mm) - 4.3
	(range 3.7-5.8)
Leaf (Mature)
Leaf shape:	orbicular to broadly	orbicular to reni-
	cordate	forme
Leaf base shape:	rounded to somewhat	cordate, lobes
	cordate, lobes small and	small and touch-
	touching to slightly	ing to slightly
	overlapping	overlapping
Leaf tip shape:	round and shallowly	rounded, rarely
	cuspidate at tip	refuse with broad
		cuspidate at tip
Leaf margin:	entire
Leaf adaxial	light-med green (147A),
surface:	glabrous except
	for sparse, un-
	branched hairs on
	veins
Leaf abaxial	light green (148A),	light green (147B);
surface:	dense, stellate	dense, stellate
	pubescence everywhere	pubescence every-
	except along main	where except along
	veins which are densely	main veins which
	tomentose with	are densely to-
	unbranched hairs	mentose with un-
		branched hairs
Leaf length (cm):	17(15.4-19.3)[15]	17.1(15.1-21.5)[15]
Leaf width (cm):	14(12.8-15.5)[15]	14.3(13.0-17.3)[15]
Leaf ratio (l/w):	1.2(1.1-1.4)[15]	1.2(1.0-1.7)[15]
Leaf petiole	4.9(4.3-5.6)[15]	4.7(3.8-5.8)[15]
length (cm):
Leaf 1° vein	pinnate; veins ter-
organization:	minating as small
	extended points or
	mucros at leaf margins
Leaf 2° vein	± parallel
organization:
Leaf puckering:	moderate	weak
Leaf variegation:	none
Leaf spines on	none
lower leaf surface:
Petiole:	200B
Peduncle:	149B
Flower
Inflorescence#:	mean 1.8 (range	mean 1.0 (range
	1-3) [23]	1-1) [17]
1° Pedicel length (cm):	4.9(3.8-6.0)[13]	5.0(3.8-5.8)[16]
2° Pedicel length (cm):	2.4(1.8-3.2)[13]	n/a
Pedicel pubescence:	minutely, densely
	tomentose, un-
	branched
Sepal#:	6.4(4-10)[10]	6.3(5-8)[15]
Sepal color:	152D	greenish-tan
Sepal pubescence:	minutely, densely
	tomentose, un-
	branched
Flower color:	10D
Flower width (cm):	6.4(5.3-7.5)[17]	5.6(4.8-6.0)[13]
Petal orientation:	overlapping: sides
	reflexed
Petal#:	6.7(5-10) [23]	7.3 (6-9) [14]
Petal length (cm):	2.8(2.2-3.3)[20]	2.6(2.3-3.1)[20]
Petal width (cm):	2.4(1.8-2.9)[20]	2.0(1.5-2.7)[20]
Petal ratio (l/w):	1.2(1.0-1.4)[20]	1.3(1.1-1.8)[20]
Petal arrangement:	overlapping
Ovary shape:	globose to oblong	globose
Ovary pubescence:	strongly expressed
	(minutely, densely
	pilose, unbranched)
Style#:	Average 32	>20
	Range 29-36
Style orientation:	upright to spreading
Stamen#:	Average 170	>40
	Range 160-190
Anther length (mm):	2.5-3.5	2.0-3.0
Chilling requirement	<800	1150
hours:
Filament:	10C
Anther:	21B
Style:	10C
Fruit
Fruit: average size (g)	60.2	77.9
	(50.4-75.0)	(64.1-89.7)
Fruit: length (mm)	64.3	63.3
	(57.0-69.8)	(61.0-65.2)
Fruit: width (max) (mm)	43.7	49.0
	(40.7-46.5)	47.1-50.8
Fruit: L/A ratio	1.46	1.29
(max width)
Fruit: width (min) (mm)	38.5	44.8
	34.9-41.3	42.6-46.2
Fruit: L/D ratio	1.68	1.42
(min width)
Fruit: core diameter	13.9	12.4
(max) (mm)	(5.0-24.3)	(7.5-14.9)
Fruit: core diameter	6.7	9.9
(min) (mm)	(3.3-15.0)	(4.6-18.8)
Fruit: locule number	37.9	38.4
	(31-51)	(31-46)
Fruit: peduncle length	59.6	46.88
(mm)	50.7-64.7	38.6-55.9
Fruit: peduncle width	2.3	2.8
(mm)	(1.7-2.7)	(2.3-3.2)
Fruit: general shape	cylindrical, ovate	cylindrical, oblong
Fruit: cross-section	round
at median
Fruit: general shape	flat, flush
of stylar end
Fruit: skin color at	199A
harvest
Fruit: skin color change	absent
during ripening
Fruit: skin color at	brown
maturity for
consumption
Fruit: hairs	present
Fruit: density of hairs	medium
Fruit: types of hairs	hirsute
Fruit: hair length (mm)	medium (1.1-2.5)
Fruit: concentration of	uniform
hairs
Fruit: adherence of	strong
hairs to skin (when
rubbed)
Fruit: core diameter	large (14.5 mm by
(at largest diameter)	7.0 mm)
Fruit: core shape	elliptical
(in cross section)
Fruit: core woody spike	present
Fruit: prominence of core	medium
woody spike
Fruit: outer pericarp	147B
color at maturity
for consumption
Fruit: inner pericarp	148B
color (locules) at ma-
turity for consumption
Fruit: core color at	147D
maturity
Fruit: seed color at	202A
maturity in flesh
Fruit: seed color	N199D
when dry
Physiochemical and
Antioxidant
Characteristics at
Harvest
pH	3.83	3.89
% Titratable Acidity	0.61	0.49
(TA)
% Soluble Solid	7.40	5.90
(SS)
Sugar/Acid Ratio	12.10	12.30
(SS/TA)
Firmness (kg)	6.05	6.27
% dry matter	20.10	17.30
Sugar (mg/g.fw)
Reducing sugar	25.87	16.01
Non-reducing sugar	11.59	18.63
Total sugar	37.46	34.64
Vitamin C
(mg/100 g.fw)
Total ascorbic acid	74.49	70.13
Ascorbic acid	67.10	61.15
Dehydroascorbic acid	7.39	8.98
TAA ratio % Hayward	1.06	1.00
AA ratio to TAA	0.90	0.82
Antioxidant
Vitamin C equivalent	92.00	68.50
antioxidant capacity
(VCEAC) (mg/100 g.fw)
Total Vit C/Total anti-	0.81	1.02
oxidant ratio (%) - X
DPPH (mg/100 g.fw)	168.90	129.60
β-carotene (mg/100 g.fw)	0.38	0.42
β-carotene ratio to	0.90	1.00
Hayward
Chlorophyll a + b ratio	1.05	1.00
to Hayward
Chlorophyll a (mg/	0.97	0.91
100 g.fw)
Chlorophyll b (mg/	0.53	0.53
100 g.fw)
Chlorophyll a + b	1.50	1.44
(mg/100 g.fw)
Sensory
Characteristics at
Consumption Stage
% Soluble Solids (SS)	16.40	14.10
% Dry matter	19.05	17.30
Firmness(kg)	<0.12	<0.12
Total Phenolics and
Total Flavonoids at
Consumption Stage
Total phenolics (mg	88.50	94.20
GAE/100 g.fw)
Total flavonoids	28.90	27.00
(mg CE/100 g.fw)

Notes regarding Table I:
1. Horticulture terminology is used in accordance with revised UPOV guidelines for kiwi.
2. Characters of comparison cultivar ‘Hayward’ are noted opposite that character when significantly different.
3. ‘Hayward’ plants were observed in the same replicated study as the new cultivar.
4. All dimensions are in millimeters unless otherwise stated; weights are in grams.

Claims

1. A new and distinct variety of Actinidia deliciosa plant named ‘AU Fitzgerald’, substantially as described and illustrated herein.