Sweetpotato plant named ‘NCPUR13-0030’

Abstract

Ipomoea batatas ‘NCPUR13-0030’ is a purple fleshed, smooth skinned, dark purple-colored, table stock sweetpotato. ‘NCPUR13-0030’ produces high yields of well-shaped and uniformly sized No. 1 sized roots. It is a mid-season variety. The flavor of the baked storage roots of ‘NCPUR13-0030’ have been judged to be good by standardized and informal taste panels.

Description

Latin name of the genus and species: The Latin name of the novel plant cultivar disclosed herein is Ipomoea batatas (L.) Lam.

Variety denomination: This new and distinct sweetpotato cultivar of Ipomoea batatas (L.) Lam. has been given the denomination ‘NCPUR13-0030’.

BACKGROUND OF THE INVENTION

Ipomoea batatas is a member of the morning glory family Convolvulaceae. This species is grown worldwide, and it exhibits a wide range of plant forms and colors. Grown by farmers worldwide, the cultivated members of Ipomoea batatas are commonly produced for consumption of their nutritious, enlarged storage roots. This contrasts with potatoes (Solanum tuberosum) that produce an edible tuber derived from an underground stem, which is similar in structure to above ground stems.

Purple fleshed sweetpotatoes are a small percentage of the US market with there being two distinct types. The first type is white skinned and purple fleshed with the main cultivar in this group being the heirloom cultivar ‘Okinawa’ (not patented), which is grown in Hawaii for the U.S. market. This heirloom cultivar is very poorly adapted to the growing regions on the mainland including North Carolina, California, Louisiana and Mississipi. The second type is purple skinned and purple fleshed. There are a few cultivars of this second type grown in the U.S., mainly ‘Mokuau’ aka ‘Molokai Purple’ (not patented), which is grown in Hawaii, and ‘Stokes Purple’ (U.S. Plant Pat. No. 17,976), which is grown on the U.S. mainland. Several different names have been used for these and other similar varieties, some of which have been previously introduced from Southeast Asia via various methods. However, none of these are particularly well adapted to North Carolina growing conditions. ‘NCPUR06-020’ (U.S. Plant Pat. No. 25,538) was developed and released for its high pigment value for industrial use, but its eating quality is poor.

‘NCPUR13-0030’ provides an improvement over ‘Stokes Purple’ and other purple-skinned, purple-fleshed cultivars known to the inventors for table stock use in terms of its adaptability, yield, and marketable shapes.

Lineage. ‘NCPUR13-0030’ originated from bulked botanical seed harvested from the open-pollinated female parent ‘NC08-0427’ (not patented) in the 2012 purple polycross nursery. The 2012 purple polycross nursery was planted in Clayton, Johnson County, N.C. The 12 genotypes present in the purple nursery were randomly mated during the course of a five-month flowering period in which seed was harvested and bulked per female parent from the 12 genotypes present in the nursery; therefore, the male parent of ‘NCPUR13-0030’ is unknown. One patented male parent (‘NCPUR06-020’ (U.S. Plant Pat. No. 25,538)) was in the nursery and represents a potential pollen source.

Seedlings from the 2012 purple polycross nursery were planted in greenhouses in Clinton, N.C. in March of 2013. A single cutting was taken from each seedling and planted in the field on May 23, 2013 in Kinston N.C. and ‘NCPUR13-0030’ was selected as a “single plant selection” on Aug. 27, 2013. This “single plant selection” included all of the storage roots derived from the single plant cutting planted on May 23^rd, with 2-10 storage roots being saved over the winter in our storage facility in Clinton, N.C. for propagation the next year via vegetive propagation in the same location.

Asexual Reproduction. The first asexual reproduction of ‘NCPUR13-0030’ occurred in Clinton, N.C. ‘NCPUR13-0030’ has been propagated as vegetative stem cuttings and/or storage root derived stem cuttings derived from adventitious sprouts emanating from its storage roots since its original selection in August of 2013. After further cycles of selection for horticultural traits and disease screenings, ‘NCPUR13-0030’ was subjected to meristem tip culture and subsequent tissue culture maintenance to eliminate viruses and pathogens via meristem tip culture. The characteristics disclosed herein for ‘NCPUR13-0030’ have remained stable and the plant has reproduced true to type through successive generations of asexual propagation.

SUMMARY OF THE INVENTION

‘NCPUR13-0030’ is a purple-fleshed, dark purple skin colored table stock sweetpotato. The storage roots of ‘NCPUR13-0030’ tend to be blocky to round elliptic and similar in length to ‘Covington’ (U.S. Plant Pat. No. 18,516) but shorter than ‘Stokes Purple’, and more uniform in size and shape than ‘Stokes Purple’. Marketable yields of ‘NCPUR13-0030’ are similar to ‘Covington’ but higher than ‘Stokes Purple’, which are the main orange fleshed and main purple fleshed sweetpotato cultivars, respectively, produced in the US. Plants from sprouted roots are ready two to three weeks before ‘Covington’, similar to ‘Stokes Purple’. The anthocyanin content for ‘NCPUR13-0030’ averages about one-third higher than ‘Stokes Purple’. The flavor of baked storage roots of ‘NCPUR13-0030’ have been judged to be good by standardized and informal taste panels, similar to ‘Stokes Purple’, the main cultivar of this type. The female parent line, ‘NC08-0427’, is cream fleshed and was no longer propagated at the time when ‘NCPUR13-0030’ was being evaluated. Consequently, ‘NC08-0427’ was not used for comparison. ‘NC08-0427’ is not grown commercially.

BRIEF DESCRIPTION OF THE DRAWINGS

The photographs in the drawings were made using conventional techniques and show the colors as true as reasonably possible by conventional photography. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description, which accurately describe the colors of the new Ipomoea batatas.

FIG. 1 is a color photograph of the above ground plant canopy produced by the new cultivar ‘NCPUR13-0030’ (abbreviated here as NCP13-0030) (left panel), ‘Stokes Purple’ (‘NC413’) (middle panel) and ‘NCPUR06-020’ (abbreviated here as NCP06-020) (right panel) 57 days after planting at in Kinston, N.C. in 2017.

FIGS. 2A-2C are color photographs of typical mature leaves of ‘NCPUR13-0030’ (abbreviated here as ‘NCP13-0030’) (FIG. 2A), ‘Stokes Purple’ (‘NC413’) (FIG. 2B), and ‘NCPUR06-020’ (abbreviated here as ‘NCP06-020’) (FIG. 2C), 57 days after planting in Kinston, N.C. in 2017.

FIGS. 3A-3C are color photographs showing typical vines and the variety of leaves of ‘NCPUR13-0030’ (abbreviated here as NCP13-0030) (FIG. 3A), ‘Stokes Purple’ (‘NC413’) (FIG. 3B) and ‘NCPUR06-020’ (abbreviated here as ‘NCP06-020’) (FIG. 3C), 57 days after planting in Kinston N.C. in 2017.

FIGS. 4A-4C are color photographs showing typical storage roots produced by ‘NCPUR13-0030’ (FIG. 4A), ‘Stokes Purple’ (‘NC413’) (FIG. 4B) and ‘NCPUR06-020’ (FIG. 4C). The photographs were taken of storage roots that had been stored in a sweetpotato storage facility for approximately three months after harvest.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of the botanical characteristics of a new and distinct cultivar of Ipomoea batatas plant given the designation ‘NCPUR13-0030’. All colors cited herein refer to The Royal Horticulture Society Colour Chart designations (The Royal Horticultural Society, London, 1995, 4^th ed.) except where general terms of ordinary dictionary significance are used. Plant descriptions are based on the standardized international sweetpotato descriptors established jointly by the International Potato Center (CIP), Lima, Peru; The Asian Vegetable Research and Development Center (AVRDC), Taipei, Taiwan; and the International Board for Plant Genetics Resources (IBPGR), Rome, Italy (CIP, AVRDC, IBPGR. 1991. Descriptors for Sweet Potato. Huaman, Z., editor. International Board for Plant Genetic Resources, Rome, Italy, 134pp.). Where dimensions, sizes, colors, and other characteristics are given, it is to be understood that such characteristics are approximations or averages set forth as accurately as practicable.

The descriptions and measurements of plant canopy reported herein were done on field grown plants 57 days after planting (DAP). The plants were grown in Kinston, N.C. under common commercial sweetpotato production practices during June through October. ‘NCPUR13-0030’ has not been observed under all possible environmental conditions; therefore, the phenotype may vary under different environmental conditions such as season, temperature, light intensity, day length, cultural conditions, and the like, without, however, any variance in the genotype.

The following discussion provides a description of the new Ipomoea batatas ‘NCPUR13-0030’ with ‘Stokes Purple’ and ‘NCPUR06-020’ for comparison. As noted above, the female parent line ‘NC08-0427’ was no longer propagated at the time when ‘NCPUR13-0030’ was being evaluated, and thus, was not used for comparison.

• Classification.
  • • Botanical name.—Ipomoea batatas (L.) Lam.
    • Common name.—Sweetpotato.
    • Variety name.—‘NCPUR13-0030’.

Growth Conditions Whole-plant Canopy Structure. FIG. 1 is a color photograph of the canopy biomass produced by the new cultivar ‘NCPUR13-0030’ contrasted with ‘Stokes Purple’ (‘NC413’), and ‘NCPUR06-020’. Measurements were collected on field-grown plants at 57 DAP on 20 measurements per trait and recorded as the mean±standard deviation. Measurements of key features are presented in Table 1.

Foliage. The leaves of ‘NCPUR13-0030’ are alternate and simple in structure, and cordate in shape with slightly to moderately lobed in shape with 0-3 lobes. (FIG. 2A and FIG. 3A). The leaves have a smooth texture and matte finish. The shape of the central lobe is semi-elliptic. Stem tip anthocyanin coloration is absent and stem tip pubescence is moderate. A detailed description of leaf traits is listed in Table 1. A typical inflorescence of ‘NCPUR13-0030’ has one cluster of 3.5±1.0 flowers per peduncle. Peduncles are green (144A) turning purple (N79A) towards the stem, averaging 8.6±1.2 cm long and about 2.6±0.3 mm in diameter. Flowers are 3.8±0.3 cm long from the base of the calyx, and the corolla 4.7±0.3 cm wide. Petals are fused to form a rounded limb with smooth edges. The inner throat color is purple (N81A) with a light purple (76B) inner and outer limb. Upper and lower flower texture is smooth. The five sepals making up the calyx are ovate with an acuminate tip. The three inner sepals are 11.0±0.0 mm long and 5.9±0.1 mm wide while the outer two sepals are shorter, 8.0±0.7 mm long and 2.5±0.1 mm wide. All sepals are green (144A) with smooth edges. The stigmata average 14.2±1.1 mm in length and are white and the stigma is inserted. Anthers are white with the style white with purple at the base (76B). No fragrance is present.

TABLE 1
Descriptive traits for ‘NCPUR13-0030’, ‘Stokes Purple’
and ‘NCPUR06-020’ measured on field plants 57 days after
planting in Kinston NC in 2017. Numerical measurements are
averages of 20 values with standard deviation.
		‘NCPUR13-	‘Stokes Purple’	‘NCPUR06-
Clone	Units	0030’	(‘NC413’)	020’
Number of		1.8 ± 0.8	1.4 ± 0.5	1.6 ± 0.5
Main vines
Main vine	cm	94 ± 20	150 ± 27	95 ± 29
length
Main vine	mm	5.7 ± 1.2	7.1 ± 1.8	7.0 ± 2.1
diameter
at base
Main vine	mm	4.1 ± 0.4	4.7 ± 0.7	5.0 ± 0.8
diameter at 50
cm from base
Number of		5.2 ± 1.4	5.5 ± 2.2	5.5 ± 1.8
lateral
branches on
main vine
Predominant		purple at base	green 144B	green 144A
vine color		(N79A) fade to		to 144B
		green 144B
		to 144C
Secondary vine		purple N79A	green with few	none
color			purple spots
			N79A
First fully	cm	4.5 ± 1.1	5.0 ± 0.8	4.0 ± 1.2
expanded
internode length
Mature leaf		green, 146A to	green, 147A	green,
color; upper		146B		between 147A
surface				and 147B
Mature leaf		green, 146B	green, 147B	green,
color; lower				between 147B
surface				and 147C
Mature leaf		green, 146B to	green, 146B to	purple spot in
venation		146C	146C	the base of
				the main
				rib, N79B
Young leaf		green, 146B to	green (146B to	green, 146B
color:		146C	146C) with slight
upper surface			purple (N79A)
			margins
Young leaf		green, 146C to	green (146B to	green, 146D
color:		146D	146C) with slight
lower surface			purple (N79A)
			margins
Mature Leaf	cm	10.1 ± 1.0	11.0 ± 0.9	11.9 ± 1.2
length
Mature leaf	cm	10.5 ± 1.0	13.5 ± 1.7	11.1 ± 0.8
width
Mature leaf		lobed	lobed	triangular to
shape; general				slightly lobed
outline
Mature leaf		very slight to	very slight to	very slight to
shape; lobing		moderate	slight	moderate
Mature leaf
shape; number		0-3	0-3	0-3
of lobes
Petiole color:		green 144B	green 144B	green 144B
primary		to 144C	to 144C
Petiole color:		none	none	none
secondary
Petiole length	cm	22.8 ± 2.6	17.1 ± 1.7	21.4 ± 2.4
Petiole diameter	mm	4.2 ± 0.6	5.2 ± 0.7	5.2 ± 0.7
Storage root		purple, N77A	purple, N79B to	purple,
skin color		to N79B	N79C	N77A to
				N79B
Storage root		purple, N77B	purple, 71A	N79B
flesh color

Storage Roots. NCPUR13-0030’ produces purple-fleshed (N77B), smooth-skinned, storage roots that are generally blocky to round elliptic. The skin color of ‘NCPUR13-0030’ is dark purple (N77A to N79B) (FIG. 4A). One of the more desirable attributes of ‘NCPUR13-0030’ is that it produces roots shorter than ‘Stokes Purple’ for soils and conditions where ‘Stokes Purple’ can be long. Length to diameter ratios of storage roots in 9 trials over four years averaged 1.8, 3.2 and 2.3 for ‘NCPUR13-0030’, ‘Stokes Purple’ and ‘NCPUR06-020’, respectively. Root number was measured for 6 trials in 2017-2019 with ‘NCPUR13-0030’ averaging 4.9 roots per plant while ‘Stokes Purple’ averaged 3.1 and ‘NCPUR06-020’ 4.3. Carbohydrate profiles, anthocyanin and asparagine levels are presented in Table 2. All three have moderate starch levels with anthocyanin levels being greater in ‘NCPUR06-020’. The flavor of the baked storage roots of ‘NCPUR13-0030’ have been judged to be good by standardized and informal taste panels comparing similarly with ‘Stokes Purple’.

TABLE 2
Select chemistry of storage roots of ‘NCP13-0030’,
‘NCPUR06-020’ and ‘Stokes Purple’ from trials from
2014 to 2018, samples measured 6-10 weeks after harvest.
			Fructose	Glucose	Sucrose
			g/100 g	g/100 g	g/100 g
Clone	n	% DM	fresh wt	fresh wt	fresh wt
‘NCP13-0030’	20	25.8 ± 2.1	0.40 ± .09	0.55 ± .14	1.44 ± .25
‘NCPUR06-020’	51	27.8 ± 1.8	0.34 ± .06	0.44 ± .08	0.87 ± .20
‘Stokes Purple’	39	28.2 ± 1.7	0.31 ± .04	0.36 ± .06	1.07 ± .21
		Starch
		g/100 g	Asparagine	TMA
Clone	n	fresh wt	mg/g fresh wt	mg/g dry wt
‘NCP13-0030’	20	53.0 ± 5.0	1.06 ± .55	1.91 ± .75
‘NCPUR06-020’	51	51.9 ± 5.6	0.73 ± .37	3.55 ± .94
‘Stokes Purple’	39	57.3 ± 4.1	0.913 ± .50	1.42 ± .68
Values are based on predictions using Near Infrared Reflectance Spectroscopy (NIRS) calibrations.
Means ± std dev.
TMA total monomeric anthocyanins

Storage Root Yield. Yield comparisons of ‘NCPUR13-0030’ are with ‘Stokes Purple’ (‘NC413’) the most common purple grown in North Carolina and ‘Covington’, the major orange fleshed sweetpotato cultivar grown in North Carolina (Table 3). ‘NCPUR06-020’ is not used in trials for table stock use and was not in these trials. In the 9 replicated yield trials, ‘NCPUR13-0030’ averaged 152% of the total marketable yield (TMY) of ‘Stokes Purple’ and 106% the TMY of ‘Covington’. ‘NCPUR13-0030’ had a higher percentage of No. 1 roots, the most valuable class, and fewer jumbos and culls (59% No. 1, 25% canner, 11% jumbo, and 4% culls) compared to ‘Stokes Purple’ (51% No. 1, 16% canner, 19% jumbo and 14% culls). Thus, for ‘NCPUR13-0030’, the value per ton harvested is higher, in addition to the higher tonnage per acre, as compared to ‘Stokes Purple’.

TABLE 3
‘NCPUR13-0030’ average yield and standard deviation and comparison
to ‘Stokes Purple’ (‘NC413’) and ‘Covington’ in 9 replicated yield
trials in 2016-2019.
	Total	Market-	% Marketable yield
	yield	able yield	%	% ‘Cov-
Trial	bu/A	bu/A	‘NC413’	ington’
2016 Clinton Purple TS	883 ± 132	791 ± 99	142 ± 48	104 ± 26
2016 Kinston Purple TS	823 ± 35	782 ± 64	206 ± 74	105 ± 9
2017 Clinton Purple TS	448 ± 127	436 ± 134	115 ± 37	120 ± 51
2017 Kinston Purple TS	395 ± 43	386 ± 41	111 ± 13	91 ± 11
2017 Scott Purple TS	506 ± 186	476 ± 176	141 ± 77	111 ± 38
2018 Kinston Purple TS	324 ± 79	324 ± 79	160 ± 50	121 ± 30
2019 Kinston NCG	598 ± 47	537 ± 83	NA	103 ± 26
2019 Kinston Purple TS	400 ± 65	368 ± 65	337 ± 155	115 ± 53
2019 Clinton Purple TS	528 ± 61	489 ± 61	136 ± 17	86 ± 16
Average	545	510	152	106
	%	%	%	%
Trial	No. 1's	Canners	Jumbo's	Culls
2016 Clinton Purple TS	47 ± 3	33 ± 8	10 ± 8	10 ± 4
2016 Kinston Purple TS	50 ± 8	30 ± 6	15 ± 4	5 ± 6
2017 Clinton Purple TS	63 ± 6	24 ± 6	10 ± 3	3 ± 4
2017 Kinston Purple TS	61 ± 13	24 ± 10	13 ± 6	2 ± 2
2017 Scott Purple TS	66 ± 4	14 ± 6	14 ± 9	6 ± 5
2018 Kinston Purple TS	68 ± 3	26 ± 3	6 ± 3	0
2019 Kinston NCG	38 ± 8	29 ± 7	13 ± 10	20 ± 8
2019 Kinston Purple TS	36 ± 5	36 ± 9	13 ± 10	15 ± 6
2019 Clinton Purple TS	47 ± 9	37 ± 9	6 ± 4	10 ± 6
Average	59	25	11	4
*50 lb bushels per acre
Size grading uses the definitions of the National Sweetpotato Collaborators Group:
US #1's - Roots 2″ to 3½″ diameter, length of 3″ to 9″, must be well shaped and free of defects.
Canners - Roots 1″ to 2″ diameter, 2″ in length.
Jumbo's - Roots that exceed the diameter, length and weight requirements of the above 2 grades, but are of marketable quality.
Total Marketable Yield - Sum of US #1, Canners and Jumbo's.
Culls - Roots >1″ in diameter and so misshapen or unattractive that they could not fit as marketable roots in any of the above
Percent US #1's - Calculated by dividing the weight of US #1's by the Total Marketable Yield weight.

Disease or Pest Resistance. The results of disease evaluations of ‘NCPUR13-0030’ are summarized in Table 4. Based on multiyear disease evaluations, ‘NCPUR13-0030’ is moderately resistant to Fusarium wilt (Fusarium oxysporum Schlect. f. sp. batatas (Wollenw.) Snyd. & Hans.), moderately susceptible to Streptomyces soil rot (Streptomyces ipomoeae (Person & W. J. Martin) Waksman & Henrici) and resistant to southern root knot nematode, Meloidogyne incognita (Kofoid & White).

TABLE 4
Disease screen results for ‘NCPUR13-0030’ by year over four years
for southern root-knot nematode (Meloidogyne incognita) (Kofoid &
White) (SRKN), fusarium wilt (Fusarium oxysporum Schlect. f sp.
batatas (Wollenw.) Snyd. & Hans.) (FW), and Streptomyces
soil rot (Streptomyces ipomoeae (Person & W. J. Martin)
Waksman & Henrici) (Field SSR).
	Year	SRKN	FW	Field SSR
	2019	—	R	—
	2018	HR	MS	—
	2017	R	R	MS
	2016	—	MR	MS
	Long term average resistance ratings for select check clones
	‘NCPUR06-0020’	MS	MR	S
	‘Stokes Purple’	R	MR	S
	‘Covington’	R	R	R
	Scale - HS—highly susceptible, S—susceptible, MS—moderately susceptible, MR—moderately resistant, R—resistant, HR—highly resistant.
	The root knot nematode rating is based on the number of galls on roots counted eight weeks after inoculation with 10,000 eggs of M. incognita race 3 in plants established in four-inch pots. Gall count classes: HR = 0; R = 1-3; MR = 4-10; MS = 11-30; S = 31-100; HS = 101+ galls. 4 reps.
	The Fusarium wilt rating involves dipping fresh cut plants in a solution of Fusarium oxysporum spores then rating for mortality and vascular tissue browning. 3 reps of five plants each are used.
	Streptomyces soil rot is screened in a field trial with high levels of SSR pressure. Plots are rated for fibrous root damage, yield and storage root lesions.

Long term storage. Sweetpotatoes from yield trials are stored and rated for the ability to last until the next crop season. They are rated on a visual pithiness scale from 0 to 4, where 0 has visible holes, to 4, where there is no visible pithiness, or they look like freshly harvested roots. This rating system is used as an estimate of how well the roots have lasted in storage. The sweetpotatoes are also rated for sprouting, another measure of long-term storage, which is also reflected in the pithiness score. ‘NCPUR13-0030’ had an average score of 2.6 averaged over 16 trials from 2014 to 2019 (Table 5). In the same years, ‘Covington’ averaged 2.4, ‘Stokes Purple’ averaged 2.4, and ‘NCPUR06-020’ averaged 2.8 on the pithiness scale, which are all considered good for storage ability. Thus, the storage ability of ‘NCPUR13-0030’ can be considered to be good. Sprouting in storage was minimal for ‘NCPUR13-0030’.

TABLE 5
Pithiness rating as an estimate of long-term storage of
‘NCP13-0030’ compared to check lines (2014-2019).
	Clone	Pithiness	# ratings
	‘NCPUR13-0030’	2.6 ± 0.6	16
	‘NCPUR06-0020’	2.8 ± 0.6	36
	‘Covington’	2.4 ± 0.4	185
	‘Stokes Purple’	2.4 ± 0.6	31
	Pithiness rating: six storage roots cut and rated in August of the year after harvest. Mean ± std dev
	Scale: 0 = large holes; 1 = holes, light areas; 2 = no holes, some light areas; 3 = slightly pithy; 4 = no pithiness.

Flood tolerance. Flood tolerance for ‘NCPUR13-0030’ appears to be slightly less than ‘Covington’ under wet conditions. ‘Covington’ is considered tolerant to wet conditions, though any cultivar will be lost if submerged. ‘NCPUR13-0030’ will show a proliferation of lenticels under wet conditions.

Claims

1. A new and distinct cultivar of Ipomoea batatas plant named ‘NCPUR13-0030’, substantially as illustrated and described herein.