U.S. patent number PP29,316 [Application Number 14/999,823] was granted by the patent office on 2018-05-29 for pecan tree named `whiddon`.
This patent grant is currently assigned to University of Georgia Research Foundation, Inc.. The grantee listed for this patent is University of Georgia Research Foundation, Inc.. Invention is credited to Darrell Sparks.
United States Patent |
PP29,316 |
Sparks |
May 29, 2018 |
Pecan tree named `Whiddon`
Abstract
A pecan tree distinguished by the following unique combination
of characteristics: Consistent and acceptable fruit production,
small fruit clusters, moderately early nut maturity, large nut
producing mammoth kernels with excellent color and no speckling,
and high resistance to scab fungus.
Inventors: |
Sparks; Darrell (Athens,
GA) |
Applicant: |
Name |
City |
State |
Country |
Type |
University of Georgia Research Foundation, Inc. |
Athens |
GA |
US |
|
|
Assignee: |
University of Georgia Research
Foundation, Inc. (Athens, GA)
|
Family
ID: |
62166349 |
Appl.
No.: |
14/999,823 |
Filed: |
July 5, 2016 |
Current U.S.
Class: |
PLT/153 |
Current CPC
Class: |
A01H
6/00 (20180501); A01H 5/08 (20130101) |
Current International
Class: |
A01H
5/08 (20180101) |
Field of
Search: |
;PLT/153 |
Other References
2014 Fort Valley State University retrieved on Aug. 1, 2017,
retrieved from the Internet at
<https://portal.nifa.usda.gov/web/areera/Reports/2014/2014-Fort-Valley-
-State-University-and-University-of-Georgia-Combined-Research-and-Extensio-
n-Annual-Report-of-Accomplishments-and-Results.pdf> pp. 1-3.
cited by examiner.
|
Primary Examiner: Hwu; June
Attorney, Agent or Firm: Klarquist Sparkman, LLP
Claims
I claim:
1. A new and distinct cultivar of pecan tree, as herein illustrated
and described.
Description
Latin name of the genus and species of the plant: Carya
illinoinensis.
Variety denomination: `Whiddon`.
BACKGROUND OF THE INVENTION
The present invention relates to a new and distinct variety of
pecan tree named `Whiddon`. My new tree can be used in gardens or
for commercial production of pecan nuts. This new tree was selected
from seedlings grown from controlled pollination at the University
of Georgia Horticulture Farm in Watkinsville, Ga., in 1990. The
`Whiddon` selection resulted from crossing `Desirable` (unpatented)
as the seed parent with `Pawnee` (unpatented) as the pollen parent
(FIG. 1). The chart of FIG. 1 illustrates the most likely pedigree
of the new `Whiddon` variety. The seedlings in the FIG. 1 chart are
unnamed. All of the varieties in the FIG. 1 chart are unpatented,
except for Starking Hardy Giant (U.S. Plant Pat. No. 1,361). The
question marks in FIG. 1 after several of the pecan trees indicate
that there is some uncertainty as to whether the identified tree is
actually a part of the lineage of the new `Whiddon` pecan tree. The
resulting tree was selected when growing in a cultivated area at
Watkinsville, Ga.
BRIEF SUMMARY OF THE INVENTION
`Whiddon` is distinguished from other pecan varieties known to the
inventor due to the following unique combination of
characteristics: consistent and acceptable fruit production, small
fruit cluster, moderately early nut maturity, large nut producing
mammoth kernels with excellent color and no speckling, high
resistance to scab fungus (Fusicladosporium effusum), moderate
resistance to black aphid (Melanocallis caryaefoliae), and moderate
resistance to pecan leaf scorch mite (Eotetranychus hicoriae).
Asexual reproduction of `Whiddon` by grafting, (top working) onto
`Desirable` pecan trees in 2004 and 2006 at a location in Albany,
Ga. and onto `Cape Fear` (unpatented) trees in 2006 at a location
in Leary, Ga. was performed in order to evaluate these trees.
Asexual reproduction of `Whiddon` has shown that the forgoing
characteristics come true to form, are firmly fixed, and are
established and transmitted through succeeding propagations.
Certain characteristics of this variety, such as growth and color,
may change with changing environmental conditions (e.g., light,
temperature, moisture, nutrient availability, or other factors).
Color descriptions and other terminology are used in accordance
with their ordinary dictionary descriptions, unless the context
clearly indicates otherwise. Color designations are made with
reference to The 2001 Royal Horticultural Society (R.H.S.) Colour
Chart.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a chart showing the pedigree of `Whiddon`.
FIG. 2 is a photograph showing scaly bark of `Whiddon`.
FIG. 3 is a photograph showing the narrow crotch of `Whiddon`.
FIG. 4 is a photograph of leaf architecture of `Whiddon`.
FIG. 5 is a photograph of young fruit of `Whiddon`.
FIG. 6 is a photograph of a mature fruit of `Whiddon`.
FIG. 7 is a photograph of nut shape and kernel characteristics of
`Whiddon`.
FIGS. 8A and 8B are comparison photographs of nut shape and kernel
characteristics of `Whiddon` vs. `Desirable`. The `Whiddon` nuts
and kernels are shown in FIG. 8A and the prior art `Desirable` nuts
and kernels are shown in FIG. 8B.
FIGS. 2-6 are of a nine year old tree.
The colors of an illustration of this type may vary with lighting
and other conditions. Therefore, color characteristics of this new
variety should be determined with reference to the observations
described herein, rather than from these illustrations alone.
DETAILED DESCRIPTION
Botanical: The following detailed description of `Whiddon` is based
on observations of the original tree growing in Watkinsville, Ga.
and of asexually reproduced progeny growing in Albany and Leary,
Ga. The original tree that was approximately 26 years old at the
time the application was filed and the observed progeny included
nine year old `Whiddon` trees. Varietal name: `Whiddon`. Parentage:
Seed parent.--`Desirable`. Pollen parent.--`Pawnee`. Tree: Overall
shape.--Upright, height to width ratio is about 2:1. FIG. 3
illustrates the characteristically narrow crotch of the upright
growth habit of `Whiddon`. Narrow crotch angles are inherent to
upright tree form. Normally, narrow crotch angles split out with
crop load. This is prevented in `Whiddon` by sequential
interlocking of cambium growth of the branch and the trunk. Note
the incipient interlocking (debarked reddish area) at the junction
of the branch and trunk in FIG. 3. Vigor.--Vigorous, prolific,
`Whiddon` fruited the second year after grafting (top working) onto
`Desirable` trees and has done so in subsequent years. Original
tree fruited 13 years from seed. Height.--Of original tree, about
32 meters. Width.--Of original tree. About 16 meters. Trunk.--Of
original tree (measured 1/2 meter above ground level) about 0.4 m
diameter. Trunk bark texture.--Initially, the bark is tight, but
the bark becomes scaly with tree maturity. Trunk bark color: Grey
(RHS 202B). Patches.--Mature trunk bark characteristically has
holes pecked by yellow bellied sapsucker (Sphyrapicus varius).
Branch color.--Branch shoots in woody stage are Grey-brown (RHS
199A) in color with Grey-brown lenticels (RHS 199D) that are
elongated and about 1 mm long by 0.05 mm wide. Internodes.--Average
length is about 2.0 cm, 3.sup.rd and 4.sup.th leaf from base of
shoot. Disease and insect resistance.--Very high resistance to scab
disease. [Fusicladosporium effusum (G. Winters) Partridge &
Morgan-Jones]. Moderate resistance to both black aphid Melanocallis
caryaefoliae (Davis) and pecan leaf scorch mite Eotetranychus
hicoriae (McGregor). Leaves.--The mature leaf is odd pinnate
compound, deciduous with leaflets having a forest green color (RHS
137A). Thirteen to 15 leaves per shoot with 11 to 17 leaflets per
mature leaf. FIG. 4 illustrates the leaf architecture of the
`Whiddon` pecan. Leaflets droop non-curving from the rachis at
about 45 degrees creating a narrow "tunnel" configuration.
Leaflets' acropetal margin flare upward producing a subtle ruffed
appearance. Leaflet blade is convoluted. Size of mature leaf
(fourth leaf from base of shoot): 31 cm long, 21.6 cm wide.
Peduncle.--Round in cross-section, tan in color (RHS 199B). The
length of the peduncle of the fourth leaf from the base is about
5.6 cm. The diameter of the peduncle of the fourth leaf from the
base is about 2.5 mm. Leaflet.--Size and shape: Fourth leaflet on
fourth leaf from base, is 15.8 cm long by 3.6 cm wide. Falcate in
shape. Base oblique. Leaflet margins are non-convoluted on mature
trees but on young vigorous trees convolution increases from basal
to apical leaves on the shoot. Texture: Upper leaflet surface
smooth. Sheen: Upper leaflet surface glossy. Petiole: Sessile or
nearly so. Margin: Serrate. Tip shape: Acuminate and narrow.
Leaflet color: Upper leaf surface: Dark green (RHS 139A). Lower
leaf surface: Green (RHS 138A). Pubescence: Upper leaf surface is
not pubescent. Lower leaf surface is slightly pubescent.
Inflorescence: General.--The `Whiddon` pecan is monoecious,
anemophilous, and protandrous (Table 1). Flowers.--Pistil flowers
are borne on a determinate spike, with staminate flowers borne on a
determinate pendulous catkin. Two-five individual pistillate
flowers per spike, borne alternately on terminally-positioned
spikes. The pistillate flower is symmetrical with no stamens or
petals. The pedicels are sessile. The staminate or catkin length is
77 mm and width is 4.9 mm. The staminate color is green (RHS 144B)
with gold pollen (RHS 3A). The involucre size, includes the stigma,
is 5.9 mm long and 2.1 mm wide. Anthocyanin is strong. The flower
has one pistil with an oxblood red (RHS 61A) stigma. The flower has
four bracts, which are green (RHS 144A), lanceolate, 5.1 mm long by
1.1 mm wide and are fused at the bases, forming a copular
involucre. Fruit: Mature fruit is dehiscent. Shuck.--Green (RHS
144B) but slightly stippled near maturity. Open widely during
dehiscence. FIG. 5 illustrates the fruit of `Whiddon` at about
seventy days before nut maturity. The shuck sutures are slightly
winged and prominent and the apex is tapered. FIG. 6 illustrates
the fruit of `Whiddon` just prior to shuck dehiscence. The shuck
surface is slightly stippled. The suture is not serrated. Fruit
split during water stage.--Not observed to be a problem. Shuck
decline.--Shuck dieback during kernel formation has not been
observed to be a problem. Nuts: (Observations from a limited number
of typical nuts from several growing seasons in Watkinsville, Ga.).
Size.--Large, length about 45 mm, width about 25 mm (width
measurement taken midway along the length of the nut and across
sutures); length to width ratio about 1.8. Nut flatness (ratio of
width across sutures to width between sutures) is about 1.0.
Form.--Oblong with a round cross-section, base shape round apex
slightly cuspidate-cuspidate asymmetric with a grooved apex.
Sutures.--Subtle, non-elevated. See the suture side of the nut
shown at the upper left-hand position in FIG. 7. The non-suture
side is shown at the upper right hand position in FIG. 7. Dorsal
grooves.--Wide, thereby decreasing the percentage kernel in the
nut. See the kernel section shown in the middle of FIG. 7 and the
dorsal side of the kernel shown at the lower right hand position of
FIG. 7. Ventral grooves.--Narrow and deep. See the ventral side of
the kernel shown at the lower left-hand position of FIG. 7.
Weight.--11.3 grams per nut (non-limiting soil moisture). Cluster
size.--About 1.8 fruits per mature cluster. Texture.--Faint ridges,
slightly rough topography is on non suture surface. Shell
thickness.--Moderately thick, 0.78 mm. Nut shell color.--Grey-brown
(RHS N199B). Kernel color.--Good color, Grayed-orange (RHS 165B).
Kernel coat.--No speckling has been observed. Kernel percentage of
nut.--About 56 percent. Nut maturity.--About October 9th. Later
than `Byrd` (U.S. Plant Pat. No. 20,867) by about 15 days.
Harvestability.--Exceptionally suitable for machine harvest.
Uniform maturity. Cracking/shelling ability.--Cracks exceptionally
well, percentage of kernels with intact halves is high. Typically,
less than one percent of chipped or broken kernels were
observed.
COMPARISONS TO OTHER VARIETIES
Tree form of `Whiddon` is unusually upright in contrast to both
parents and almost all other pecan cultivars. Thus, `Whiddon` trees
can be planted in higher tree density than most cultivars. The
timing of bud break of `Whiddon` is similar to `Huffman` (U.S.
Plant Pat. No. 25,465), `Morrill` (U.S. Plant Pat. No. 23,335), and
`Stuart` (unpatented) pecan trees (Table 2). Thus, `Whiddon` is
less susceptible to late-spring freezes than `Byrd` (U.S. Plant
Pat. No. 20,867), `Cunard` (U.S. Plant Pat. No. 24,373),
`Desirable`, and `Treadwell` (U.S. Plant Pat. No. 25,740). The
leaves of `Whiddon` are forest green as in `Pawnee`, but are unlike
the pale green of `Desirable`. Leaflet orientation is similar to
seed parent `Desirable` and most pecan genotypes; that is leaflets
droop from the rachis and is unlike pollen parent `Pawnee` where
the opposite leaflets are oriented at 180 degrees relative to each
other. Leaflet margins on vigorous shoots are convoluted. The
stigmatic surface of `Whiddon` is oxblood, similar to the oxblood
color of both parents and in contrast to the green stigma of
`Wichita` (unpatented) and some other cultivars. `Whiddon` like
`Tom` (U.S. Plant Pat. No. 26,705) is highly resistant to the scab
fungus (Table 3) and contrasts with the high susceptibility of both
parents and to almost all other pecan cultivars. In the humid
southeastern United States, resistance is a major attribute of
`Whiddon`. Mature bark is pecked by yellow bellied sapsucker as in
`Stuart` and `Wichita`.
Table 1 below compares periods of pollen shedding and stigma
receptively for `Whiddon` and selected other pecan cultivars (all
unpatented) in April 2012, Watkinsville, Ga.
TABLE-US-00001 TABLE 1 April 9 10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 27 28 29 30 Protandrous cultivars `Cheyenne` * . . .
. . . . . . ___________ `Desirable` * . . . . . . . . . _______
`Whiddon` . . . . . . . . . _____________ Protogynous `Elliott` * .
. . . . . . . . . . . . . . . . . _________ `Schley` * . . . . . .
. . . ________ `Stuart` * . . . . . . . . . _______ . . . . . . . .
. = Period of stigma receptivity. _____ = Period of pollen shedding
* Unpatented
Table 2 below compares bud break date for `Byrd`, `Tom`, `Huffman`,
`Morrill`, `Cunard`, `Treadwell`, `Stuart`, `Whiddon`, and
`Desirable` pecans. Observations were of trees growing in
Watkinsville, Ga.
TABLE-US-00002 TABLE 2 Cultivar Bud break date.sup.z `Byrd` 3/27c
`Tom` 4/2a `Huffman` 3/30b `Morrill` 3/30b `Cunard` 3/26c
`Treadwell` 3/27c `Stuart` 3/31ab `Whiddon` 3/30b `Desirable` 3/27c
Means followed by the same letter are not statistically different,
P .ltoreq. 0.05, n = 6. .sup.zAverage of years 2005, 08, 09, 10,
11, 12. Replication over years.
Table 3 below compares fruit scab susceptibility of `Whiddon` with
`Byrd,` `Morrill,` `Cunard`, `Treadwell`, `Tom`, `Huffman` and
`Desirable`. In addition, `Pawnee` has been observed to be more
susceptible to scab disease than `Whiddon` when observed at two
Georgia growing locations.
TABLE-US-00003 TABLE 3 Fruit scab.sup.x Leary.sup.y
Watkinsville.sup.z Cultivar 2010 2011 2012 2013 5 yr. mean.sup.y
`Byrd` 1.1c 1.0b 1.0b 1.0b 1.7bc `Morrill` -- 1.0b 1.0b 1.0b 1.8b
`Cunard` 1.6b 1.0b 1.0b 1.0b 2.3b `Treadwell` 1.0c 1.0b 1.0b 1.0b
2.2b `Tom` -- 1.0b 1.0b 1.0b 1.0c `Huffman` 1.0c 1.0b 1.0b 1.0b
1.0c `Whiddon` 1.0c 1.0b 1.0b 1.0b 1.0c `Desirable` 3.2a 1.4a 4.3a
2.8a 3.3a Means followed by the same letter are not statistically
different, P .ltoreq. 0.05. .sup.x1 = no lesions, 2 = occasional
lesions, <10% of fruit with scab, 3 = lesions common on fruit
but not damaging, 1-50% of fruit with scab, 4 = wide spread lesions
on fruit but not damaging, 51-75% of fruit with scab, 5 =
widespread lesions on fruit, fruit size suppressed. Fungicides
applied at both locations. .sup.yn = 19, sprayed with fungicide.
.sup.zn = 5, sprayed with fungicide.
Table 4 below compares nut characteristics of `Treadwell`, `Byrd`,
`Tom`, `Cunard`, `Morrill`, `Elliott`, `Huffman`, `Whiddon`, and
`Desirable` pecans. Observations were of trees growing in Albany,
Ga., from 2009-2012.
TABLE-US-00004 TABLE 4 Nut Shell Nut Wt./nut Nuts/lbs length
Length/ Nut .sup.y thickness Kernel maturity Cultivar (g) (no.)
(mm) width .sup.z flatness (mm) (%) date .sup.x `Treadwell` 9.5ef
48cd 41.5e 1.92b 0.97d 0.70cd 62.2b 24a `Byrd` 8.9f 51c 42.4e
1.88bc 1.04b 0.51e 62.3b 24a `Tom` 7.8g 58b 36.3f 1.64e 0.96d 0.84a
54.7d 25a `Cunard` 11.1cb 41e 52.2a 2.18a 1.03b 0.66cd 62.5b 26a
`Morrill` 10.1de 46d 49.2b 2.07a 1.11a. 0.63d 65.9a 35b `Elliott`
7.1h 64a 32.5g 1.39f 1.04b 0.70cd 52.0e 38b `Huffman` 12.2a 37e
44.7d 1.65e 1.03b 0.72c 55.5c 33b `Whiddon` 11.3b 41e 45.2cd
1.81bcd 1.01c 0.78b 55.9c 39b `Desirable` 10.4cd 44d 46.7c 1.76cde
1.11a 0.72c 54.8d 50c Means followed by the same letter are not
statistically different, P < 0.05, n = 4. .sup.z Length to width
ratio = nut length divided by width. Width was measured midway the
length of the nut and across the suture. .sup.y Nut flatness =
ratio of nut width across suture to width between suture.
Measurement was made midway the length of the nut. .sup.x Date when
shuck dehiscence had occurred on 50% of the fruit, from September
1.
Pecan nuts of large size that mature relatively early command a
premium price. The price per pound normally declines as the harvest
becomes later. Consequently, cultivars that exhibit early maturity
at harvest are commercially important. The color of a kernel's seed
coat (lighter is preferred), and the percentage kernel of the nut
also affects the selling price of pecans. Although the nut maturity
of `Whiddon` is about 15 days later than nut maturity of `Byrd`, it
is about 11 days earlier than `Desirable` (Table 4). `Desirable` is
believed to be the leading cultivar now being planted in new
orchards in Georgia. Even though the nut maturity of `Whiddon` is
later than `Byrd`, the maturity date is still early enough to be
considered an early market cultivar. The later harvest date of
`Whiddon` is advantageous in one respect because a number of
growers of pecans in southwest Georgia also grow peanuts. The
harvest date of `Byrd` `Cunard`, `Pawnee`, `Tom`, and `Treadwell`
pecans conflicts with the peanut harvest date. `Whiddon` matures at
the end of the peanut harvesting season, making it a more suitable
early cultivar for peanut growers that can harvest `Whiddon` pecans
following the peanut harvest. In addition to use in a new planting,
`Whiddon` is well suited as a replacement tree or as an inter plant
in a `Stuart`-`Schley` (unpatented), `Desirable` orchard, a common
combination in the southeastern United States. The nut maturity
date of `Whiddon` is similar to `Stuart` and `Schley`; allowing a
once over harvest of the blended nuts. In contrast to `Treadwell`,
and similar to `Tom`, the shuck opens widely which minimizes
premature germination and promotes rapid pre harvest drying of the
nut. Unlike `Huffman` and `Treadwell`, shuck surface is not russet.
Also unlike `Huffman`, shuck sutures of `Whiddon` are not
serrated.
From Table 4, `Whiddon` nuts are large (wt./nut), equal in size to
`Cunard` and larger than `Morrill` and `Desirable` and less than
`Huffman`. Consequently, the large kernels of `Whiddon` are well
suited to the "mammoth half" market. Nut length is less than
`Cunard` and `Morrill` and similar to `Desirable` and `Huffman`.
General nut shape (length/width) is similar to `Desirable`,
`Treadwell`, and `Byrd`, but is less oblong than `Cunard` and
`Morrill`. Cross-section (nut flatness) of `Whiddon` nuts are near
round (flatness ratio 1.01) and intermediate to `Huffman` and
`Desirable` and more symmetrical than `Treadwell`, `Byrd`, `Tom`,
`Cunard`, `Morrill`, `Elliott`, `Huffman`, and `Desirable`. The
shell is thicker in `Whiddon` than `Huffman` and `Desirable`. The
percentage kernel of `Whiddon` is higher than `Desirable` and
similar to `Huffman`. In pecans, the percentage kernel is a direct
function of shell thickness and the percentage of the shell cavity
filled with kernel. The percentage kernel of `Huffman` and
`Desirable`, in spite of a thinner shell, is not greater than
`Whiddon`; because of a concave kernel, dorsal grooves that are
wide, and a central partition that is thick, which reduces the
percentage of shell cavity filled with kernel. The percentage
kernel of `Whiddon` nuts is higher than the industry standard
`Desirable`. FIGS. 8A and 8B show a comparison of typical nuts and
kernels of `Whiddon` and `Desirable`. In FIG. 8A, left to right,
the suture side and non-suture side of the `Whiddon` nuts are
shown. This FIG. also shows a cross-section of the kernel in the
middle and, left to right, the ventral side and dorsal side of the
`Whiddon` kernels. FIG. 8B, left to right, the suture side and
non-suture side of the `Desirable` nut, a cross-section of the
`Desirable` kernel is shown in the middle; and, left to right,
ventral and dorsal sides of the `desirable` kernel are also
shown.
Under stress, primarily fruiting stress, and when `Pawnee` pecan
trees are grown in humid southeastern United States, the kernel's
seed coat of `Pawnee` pecans can develop conspicuous and
unattractive dark spots. This speckling reduces the marketability
of these nuts. Speckling has not been observed to be a problem of
`Whiddon` nuts grown in Georgia. Kernel color of `Whiddon` fruit is
good (FIGS. 7 and 8) and kernel color retention is good. In
addition, unlike `Whiddon`, during a heavy "on" nut production year
for `Pawnee` trees growing in Georgia, kernel development is
relatively poor, resulting in a high percentage of the nuts being
unmarketable or of reduced value.
Table 5 below compares precocity of `Cunard`, `Byrd`, `Treadwell`,
`Tom`, `Desirable`, `Morrill`, `Whiddon`, `Elliott`, `Huffman`, and
`Stuart` pecans.
TABLE-US-00005 TABLE 5 Cultivar Years to initial fruiting.sup.z
`Cunard` 2 `Byrd` 3 `Treadwell` 3 `Tom` 3 `Desirable` 4 `Morrill` 4
`Whiddon` 4 `Elliott` 5 `Huffman` 5 `Stuart` 6 .sup.zYears from
transplanting from the nursery.
Table 6 below compares alternate bearing tendency of `Byrd`,
`Treadwell`, `Huffman`, `Tom`, `Cunard`, `Morrill`, and `Whiddon`
pecans. Observations were of trees growing in Albany, Ga.
TABLE-US-00006 TABLE 6 Years to fruiting Years Cultivar (no.) until
bearing alternate (no.).sup.y Byrd 2 3 Treadwell 2 3 Huffman 2
>6 Tom 2 >6 Cunard 2 10.sup.z Morrill 2 >9 Whiddon 2 8
.sup.yYears after top working mature trees to the respective
cultivar. Top working simulates a mature tree and allows for
earlier evaluation of alternate bearing, kernel development under
heavy fruit load, and suitability for mechanical harvest and ease
of fruit thinning. .sup.zAnnual production maintained by fruit
thinning.
Table 7 below compares pounds/tree, weight per nut, nuts per pound,
percentage kernel of trees top worked.sup.z, namely the comparison
is of `Morrill`, `Cunard`, `Treadwell`, `Huffman`, `Tom`, and
`Whiddon` pecans, observed in Albany, Ga., from 2009-2012.
TABLE-US-00007 TABLE 7 Cultivar Lbs/tree wt./nut (g) Nuts/lb. (no.)
Kernel (%) `Morrill` 35b 10.1c 46d 65.9a0 `Cunard`.sup.y 44ab 11.1b
41e 62.5b `Treadwell`.sup.y 30ab 9.5cd 48cd 62.2b `Huffman` 32ab
12.2a 37e 55.5cd `Tom` 57a 7.8e 58b 54.7cd `Whiddon` 37ab 11.3b 41e
55.9c Means followed by the same letter within a column are not
statistically different, P .ltoreq. 0.05, n = 4. .sup.zTop working
simulates a mature tree and allows for earlier evaluation of
alternate bearing, kernel development under heavy fruit load, and
suitability for mechanical harvest and ease of fruit thinning
.sup.yCunard and Treadwell were fruit thinned as needed. About 50%
of the fruit was removed. Other cultivars were not fruit
thinned.
`Whiddon` is not precocious relative to `Byrd` (Table 5). Also, the
original `Whiddon` tree bore its first fruit the 13.sup.th year
from planting as seed. In comparison, the original tree of `Byrd`
first fruited the 7.sup.th year from planting as seed. `Whiddon` is
not as precocious as `Byrd` as is also indicated by the onset of
alternate fruit-bearing in `Byrd` trees the third year from top
working in contrast to alternate fruit bearing in `Whiddon` trees
in the 8.sup.th year (Table 6). Precocity of `Whiddon` is similar
to `Desirable` and `Morrill` (Table 5). Although not precocious,
prolificacy as mature top worked trees is good and similar to
`Morrill`, `Cunard`, `Treadwell`, `Huffman`, and `Tom` (Table 7).
Thus far, alternate bearing of `Whiddon` has been relatively minor
or about 50% during the "off" year relative to the "on" year. Thus,
the mainly annual production of `Whiddon` is as in `Desirable` and
both `Whiddon` and `Desirable` have a small fruit cluster size
(Table 8).
As indicated in (Table 8), the cluster size of `Whiddon` and
`Desirable` is similar. It does appear that `Whiddon` has lower
density of fruiting shoots than `Byrd` and is similar to
`Desirable`. Because of the small cluster size and consistent
production exhibited by `Whiddon` following top working to mature
pecan trees, `Whiddon` is expected to bear quite consistently with
increasing tree maturity as occurs with its seed parent
`Desirable`. `Whiddon` is superior to `Desirable` in having a
larger nut, higher percentage kernel, and high resistance to scab
disease.
Table 8 below compares fruit cluster size of `Byrd`, `Desirable`,
`Huffman`, `Tom`, `Morrill`, `Pawnee`, Cunard`, and `Treadwell`,
`Elliott`, and `Whiddon` pecans. Observations were of trees growing
in Watkinsville, Ga. Data are averages of three years, 2005, 2006,
and 2008.
TABLE-US-00008 TABLE 8 Cultivar Fruits/cluster(no.).sup.z `Byrd`
3.1a `Desirable` 1.8c `Huffman` 1.6c `Tom` 2.8b `Morrill` 2.9ab
`Pawnee` 3.2a `Cunard` 3.2a `Treadwell` 2.7b `Elliott` 2.8b
`Whiddon` 1.8c Means followed by the same letter are not
statistically different, P .ltoreq. 0.05, n = 30. .sup.zCluster
counts made after the second drop was completed.
Tables 9-11 below compares N scorch, black pecan aphids, and pecan
leaf scorch mite resistance of `Whiddon` to other pecan
varieties.
Table 9 below compares leaf susceptibility of `Byrd`, `Morrill`,
`Cunard`, `Treadwell`, `Whiddon`, `Huffman`, and `Desirable` pecans
to N scorch.sup.y. Observations were of trees growing in Leary, Ga.
in 2009.
TABLE-US-00009 TABLE 9 Cultivar Leaf rating.sup.z `Byrd` 1.2c
`Morrill` 1.5c `Cunard` 1.1c `Treadwell` 1.0c `Whiddon` 1.1c
`Huffman` 3.8b `Desirable` 4.7a Means followed by the same letter
are not statistically different, P .ltoreq. 0.05%, n = 19. .sup.yN
scorch can cause severe premature defoliation in May and July and
is induced by an imbalance of N and K in the leaf. .sup.z1 = no
scorch 2 = <1% of leaves with scorch 3 = 2 to 20% 4 = 21 to 40%
5 = >41%
Table 10 below compares leaf susceptibility of `Byrd`, `Huffman`,
`Morrill`, `Cunard`, `Tom`, `Treadwell`, `Sumner`, `Whiddon`, and
`Desirable` to black pecan aphid. Observations were of trees
growing in Leary, Ga.
TABLE-US-00010 TABLE 10 Leaf rating.sup.z Year Cultivar (2009)
(2010) (2011) `Byrd` 1.5ef 1.7cd 1.7bc `Huffman` 1.4efg -- 1.4cd
`Morrill` 2.3b 2.0ab 1.9b `Cunard` 1.1g 1.9abc 1.8b `Tom` 1.1g --
1.2de `Treadwell` 1.9cd 2.2a 2.4a `Sumner` 2.8a -- 1.9b `Whiddon`
1.9c 2.0ab 2.0b `Desirable` -- 2.0ab 1.0e Means followed by the
same letter are not statistically different, P .ltoreq. 0.05%, n =
19. .sup.z1 = no injury, 2 = <1% of leaves with injury, 3 =
1-10% of leaves with injury, 4 = 11-50% of leaves with injury, 5 =
>50% of leaves with injury and partial defoliation.
Table 11 below compares leaf susceptibility of `Byrd`, `Tom`,
`Morrill`, `Huffman`, `Cunard`, `Treadwell`, `Whiddon`, `Sumner`,
and `Desirable` to pecan leaf scorch mite. Observations were of
trees growing in Leary, Ga.
TABLE-US-00011 TABLE 11 Leaf rating.sup.z Cultivar 2009 2010 `Byrd`
1.1f 1.1c `Tom` 1.1f -- `Morrill` 1.2f 1.2c `Huffman` 1.6de --
`Cunard` 2.2bc 1.8ab `Treadwell` 2.7a 1.9a `Whiddon` 1.6de 1.6b
`Sumner` 1.6de -- `Desirable` -- 1.0c Means followed by the same
letter are not statistically different, P .ltoreq. 0.05%, n = 19.
.sup.z1 = no damage, 2 = trace, 3 = multiple lesions, 4 = minor
defoliation, 5 = severe defoliation.
`Whiddon` has excellent resistance to N scorch, in contrast to
`Huffman` and especially to its seed parent `Desirable` (Table 9).
Resistance to black pecan aphid by `Whiddon` is similar to
`Desirable` (Table 10) and resistance to pecan leaf scorch mite of
`Whiddon` is similar to `Huffman` (Table 11).
Under the humid growing conditions in southeastern United States,
the pecan fruit is highly susceptible to splitting during the
"water stage" (liquid endosperm stage) of fruit development. Fruit
split can occur following rain and accompanying prolonged high
humidity in early August in Georgia. Water split has not been
observed in `Whiddon`. The lack of split may be due to the timing
of fruit development. Water split is most likely to occur on
cultivars when the maximum liquid endosperm stage occurs during the
first two weeks in August; which often coincides with the rainy
period in Georgia. Typically, rainfall in Georgia sharply decreases
after August 15th. The maximum liquid endosperm stage in `Whiddon`
fruit grown in Georgia usually occurs after August 15th.
The `Whiddon` pecan tree is therefore an improved new and distinct
pecan.
* * * * *
References