United States Patent 15
`Hoffbeck
`
`0008
`
`[11] Patent Number:
`
`[45] Date of Patent:
`
`5,463,173
`Oct. 31, 1995
`
`[54]
`
`INBRED CORN LINE PHR61
`
`[75]
`
`Inventor: Loren J. Hoffbeck, Tipton, Ind.
`
`[73] Assignee: Pioneer Hi-Bred International, Inc.,
`Des Moines, lowa
`
`(21] Appl. No.: 164,586
`
`[22] Filed:
`
`Dec. 9, 1993
`
`Related U.S. Application Data
`
`[63] Continuation-in-part of Ser. No. 649,800, Feb. 1, 1991,
`abandoned.
`
`[51]
`
`Int. CU acsssscestcssssssneseeesees AO1H 5/00; AQ1H 1/00;
`C12N 5/04
`
`[52] U.S. Ceeee 800/200; 800/250; 800/DIG. 56;
`47/58; 435/240.4; 435/240.49; 435/240.50
`[S58] Field of Search ooo...cceeeseeceseees 800/200, 205,
`800/DIG. 56;-47/58, 58.03, 58.05; 435/240.4,
`145.49
`
`OTHER PUBLICATIONS
`
`Wych (1988) In Corn & Corn Improvement. Editor 6, F
`Sprague et al. pp. 565-607 ASA pub 183rd Edition.
`Hallauer et al. (1988) IB1D pp. 463-564.
`
`Meghiji et al. (1984) Crop Science vol. 24, pp. 545-549.
`Poehlmen (1987) Breeding Field Crops AUI Publishing Co.
`pp. 237-246.
`(1988) Corn & Corn Improvement ASA
`Phellips et al.
`monograph #18, 3rd edition G. F. Sprague editor, pp.
`345349 & 356-357.
`
`Sass, (1977) Corn & Corn Improvement ASA monograph.
`#18 2nd edition. pp. 89-110.
`Troyer et al. (1985) Crop Science vol. 25. pp. 695-697.
`
`Primary Examiner—Gary Benzion
`Altorney, Agent, or Firm—Pioneer Hi-Bred International,
`Inc.
`
`(37]
`
`ABSTRACT
`
`According to the invention, there is provided an inbred corn
`line, designated PHR61. This invention thus relates to the
`plants and seeds of inbred corn line PHR61 and to methods
`for producing a corn plant produced by crossing the inbred
`line PHR61 with itself or with another corn plant. This
`invention further relates to hybrid corn seeds and plants
`produced by crossing the inbred line PHR61 with another
`corn line or plant.
`
`6 Claims, No Drawings
`
`Inari Exhibit 1041
`Inari Exhibit 1041
`Inari v. Pioneer
`Inari v. Pioneer
`
`

`

`5,463,173
`
`1
`INBRED CORN LINE PHR61
`
`CROSS REFERENCE TO RELATED
`APPLICATION
`
`This is a continuation-in-part of prior application Ser. No.
`07/649,800, filed Feb. 1, 1991, now abandoned.
`
`FIELD OF THE INVENTION
`
`This inventionis in the field of corn breeding, specifically
`relating to an inbred corn line designated PHR61.
`
`BACKGROUNDOF THE INVENTION
`
`The goal of plant breeding is to combine in a single
`variety/hybrid various desirable traits. For field crops, these
`traits may include resistance to diseases and insects, toler-
`ance to heat and drought, reducing the time to crop maturity,
`greater yield, and better agronomic quality. With mechanical
`harvesting of many crops, uniformity of plant characteristics
`such as germination and stand establishment, growth rate,
`maturity, and fruit size, is important.
`Field crops are bred through techniques that take advan-
`tage of the plant’s method of pollination. A plant is self-
`pollinated if pollen from one fiower is transferred to the
`same or another flower of the same plant. A plant is
`cross-pollinated if the pollen comes from a flower on a
`different plant.
`Plants that have beenself-pollinated and selected for type
`for many generations become homozygous at almost all
`gene loci and produce a uniform population of true breeding
`progeny. A cross between two homozygouslines produce a
`uniform population of hybrid plants that may be heterozy-
`gous for many gene loci. A cross of two plants each
`heterozygous at a number of gene loci will produce a
`population of hybrid plants that differ genetically and will
`not be uniform.
`
`Cor plants (Zea mays L.) can be bred by both self-
`pollination and cross-pollination techniques. Corn has sepa-
`rate male and female flowers on the same plant, located on
`the tassel and the ear, respectively. Natural pollination
`occurs in corn when wind blows pollen from the tassels to
`the silks that protrude from the tops of the incipient ears.
`The development of corn hybrids requires the develop-
`ment of homozygous inbred lines, the crossing of these
`lines, and the evaluation of the crosses. Pedigree breeding
`and recurrent selection breeding methods are used to
`develop inbred lines from breeding populations. Breeding
`programs combine the genetic backgrounds from two or
`more inbred lines or various other broad-based sources into
`breeding pools from which new inbred lines are developed
`by selfing and selection of desired phenotypes. The new
`inbreds are crossed with other inbred lines and the hybrids
`from these crosses are evaluated to determine whichofthose
`have commercial potential.
`Pedigree breeding starts with the crossing of two geno-
`types, each of which may have one or more desirable
`characteristics that is lacking in the other or which comple-
`ment the other. If the two original parents do not provideall
`of the desired characteristics, other sources can be included
`in the breeding population. In the pedigree method, superior
`plants are selfed and selected in successive generations. In
`the succeeding generationsthe heterozygous condition gives
`way to homogeneouslinesas a result of self-pollination and
`selection. Typically in the pedigree method of breedingfive
`or more generations of selfing and selection is practiced:
`
`15
`
`20
`
`25
`
`30
`
`40
`
`45
`
`30
`
`55
`
`60
`
`65
`
`2
`F,—- F,; F,>F,; F,-F,; F,-F,, ete.
`Backcrossing can be used to improve an inbred line.
`Backcrossing transfers a specific desirable trait from one
`inbred or sourceto an inbred that lacks that trait. This can be
`accomplished for example by first crossing a superior inbred
`(A) (recurrent parent) to a donor inbred (non-recurrent
`parent), which carries the appropriate gene(s) forthe trait in
`question. The progenyofthis cross is then mated backto the
`superior recurrent parent (A) followed by selection in the
`resultant progeny for the desired trait to be transferred from
`the non-recurrent parent. After five or more backcross gen-
`erations with selection for the desired trait, the progeny will
`be heterozygous for loci controlling the characteristic being
`transferred, but will be like the superior parent for most or
`almostall other genes. The last backcross generation would
`be selfed to give pure breeding progenyfor the gene(s) being
`transferred.
`
`A single cross hybrid corn variety is the cross of two
`inbred lines, each of which has a genotype which comple-
`ments the genotype of the other. The hybrid progenyof the
`first generation is designated F,. In the development of
`hybrids only the F, hybrid plants are sought. Preferred F,
`hybrids are more vigorous than their inbred parents. This
`hybrid vigor, or heterosis, can be manifested in many
`polygenic traits, including increased vegetative growth and
`increased yield.
`The developmentof a hybrid corn variety involves three
`steps: (1) the selection of plants from various germplasm
`pools; (2) the selfing of the selected plants for several
`generations to produce a series of inbred lines, which,
`although different from each other, each breed true and are
`highly uniform; and (3) crossing the selected inbred lines
`with unrelated inbred lines to produce the hybrid progeny
`(F,). During the inbreeding process in corn, the vigor of the
`lines decreases. Vigor is restored when two unrelated inbred.
`lines are crossed to produce the hybrid progeny (F,). An
`important consequence of the homozygosity and homoge-
`neity of the inbred lines is that the hybrid between any two
`inbreds will always be the same. Once the inbredsthat give
`a superior hybrid have been identified, the hybrid seed can
`be reproducedindefinitely as long as the homogeneity of the
`inbred parents is maintained.
`A single cross hybrid is produced when two inbred lines
`are crossed to produce the F, progeny. A doublecross hybrid
`is produced from four inbred lines crossed in pairs (AXB and
`CxD)and then the two F, hybrids are crossed again (AXB)x
`(Cx D). Muchofthe hybrid vigor exhibited by F, hybridsis
`lost in the next generation (F,). Consequently, seed from
`hybrid varieties is not used for planting stock.
`Corn is an important and valuable field crop. Thus, a
`continuing goal of plant breeders is to develop high-yielding
`corn hybrids that are agronomically sound based on stable
`inbred lines. The reasons for this goal are obvious:
`to
`maximize the amount of grain produced with the inputs used
`and minimize susceptibility to environmental stresses. To
`accomplish this goal,
`the com breeder must select and
`develop superior inbred parental lines for producing hybrids.
`This requires identification and selection of genetically
`unique individuals which in a segregating population occur
`as the result of a combination of crossover events plus the
`independentassortmentof specific combinationsofalleles at
`many gene loci which results in specific genotypes. Based
`on the number of segregating genes,
`the frequency of
`occurrence of an individual with a specific genotype is less
`than 1 in 10,000. Thus, even if the entire genotype of the
`parents has been characterized and the desired genotype is
`
`

`

`5,463,173
`
`3
`known, only a few if any individuals having the desired
`genotype may be found in a large F, or Sg population.
`Typically, however, the genotype of neither the parents nor
`the desired genotype is known in any detail.
`
`SUMMARY OF THE INVENTION
`
`According to the invention, there is provided a novel
`inbred corn line, designated PHR61. This invention thus
`relates to the seeds of inbred corn line PHR61, to the plants
`of inbred corn line PHR61, and to methods for producing a
`corn plant produced by crossing the inbred line PHR61 with
`itself or another corn line. This invention further relates to
`hybrid corn seeds and plants produced by crossing the
`inbred line PHR61 with another corn line.
`
`DEFINITIONS
`
`In the description and examples that follow, a number of
`terms are used herein. In order to provide a clear and
`consistent understanding of the specification and claims,
`including the scope to be given such terms, the following
`definitions are provided:
`BAR PLT = BARREN PLANTS. This is the percent of
`plants per plot that were not barren (Jack ears).
`BRT STK = BRITTLE STALKS. Thisis a measure of the
`stalk breakage near the time of pollination, and is an
`indication of whether a hybrid or inbred would snap or break
`near the time of flowering under severe winds. Data are
`presented as percentage of plants that did not snap.
`BU ACR = YIELD (BUSHELS/ACRE). Actual yield of
`the grain at harvest adjusted to 15.5% moisture. ABS is in
`absolute terms and % MNis percent of the mean for the
`experiments in which the inbred or hybrid was grown.
`DRP EAR = DROPPED EARS. This is a measure of the
`number of dropped ears per plot and represents the percent-
`age of plants that did not drop ears prior to harvest.
`EAR HT = EAR HEIGHT. The ear height is a measure
`from the ground to the top developed ear node attachment
`and is measured in inches.
`
`EAR SZ = EARSIZE.A 1 to 9 visual rating of ear size.
`The higher the rating the larger the ear size.
`EST CNT = EARLY STAND COUNT.Thisis a measure
`of the stand establishment in the spring and represents the
`number of plants that emerge on a per plot basis for the
`inbred or hybrid.
`GDU SHD = GDU TO SHED. The number of growing
`degree units (GDUs) or heatunits required for an inbred line
`or hybrid to have approximately 50 percent of the plants
`shedding pollen and is measured from the time of planting.
`Growing degree units are calculated by the Barger Method,
`where the heat units for a 24-hour period are:
`
`GDU= (Max. temp, + Min. temp)
`
`~50
`
`The highest maximum temperature used is 86° F. and the
`lowest minimum temperature used is 50° F. For each inbred
`or hybrid it takes a certain number of GDUsto reach various
`stages of plant development.
`GDU SLK = GDU TO SILK. The number of growing
`degree units required for an inbred line or hybrid to have
`approximately 50 percent of the plants with silk emergence
`from time of planting. Growing degree units are calculated
`by the Barger Method as given in GDU SHDdefinition.
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`GRN APP = GRAIN APPEARANCE.This is a 1 to 9
`rating for the general appearance of the shelled grain asit is
`harvested based on suchfactors as the colorof the harvested
`grain, any mold on the grain, and any cracked grain. High
`scores indicate good grain quality.
`MST = HARVEST MOISTURE. The moisture is the
`actual percentage moisture of the grain at harvest.
`PLT HT = PLANT HEIGHT. This is a measure of the
`height of the plant from the groundto the tip of the tassel in
`inches.
`
`to 9 visual rating
`POL SC = POLLEN SCORE. A |
`indicating the amount of pollen shed. The higher the score
`the more pollen shed.
`POL WT = POLLEN WEIGHT.Thisis calculated by dry
`weight of tassels collected as shedding commences minus
`dry weight from similar tassels harvested after shedding is
`complete. % MNis percent of the mean for the experiments
`in which the inbred or hybrid was grown.
`PRM = PREDICTED RM. Thistrait, predicted relative
`maturity (RM), is based on the harvest moisture of the grain.
`The relative maturity rating is based on a known set of
`checksandutilizes standard linear regression analyses and is
`referred to as the Minnesota Relative Maturity Rating Sys-
`tem.
`
`RT LDG = ROOT LODGING.Rootlodging is the per-
`centage ofplants that do not root lodge; plants that lean from
`the vertical axis at an approximately 30° angle or greater
`would be counted as root lodged.
`SCT GRN = SCATTER GRAIN.A 1 to 9 visual rating
`indicating the amountof scatter grain (lack ofpollination or
`kernel abortion) on the ear. The higher the score the less
`scatter grain.
`SDG VGR = SEEDLING VIGOR.This is the visual
`rating (1 to 9) of the amount of vegetative growth after
`emergenceat the seedling stage (approximately five leaves).
`A higher score indicates better vigor.
`SEL IND = SELECTION INDEX.Theselection index
`gives a single measure of the hybrid’s worth based on
`information for upto five traits. A corn breeder may utilize
`his or her ownsetoftraits for the selection index. Oneof the
`traits that is almost always included is yield. The selection
`index data presented in the tables represent the mean value
`averaged across testing stations.
`STA GRN = STAY GREEN.Stay green is the measure of
`plant health near the time of black layer formation (physi-
`ological maturity). A high score indicates better late-season
`plant health.
`STK CNT = NUMBER OF PLANTS. Thisis the final
`stand or numberof plants per plot.
`STK LDG = STALK LODGING.Thisis the percentage
`of plants that did not stalk lodge (stalk breakage) as mea-
`sured by either natural lodging or pushing the stalks and
`determining the percentage of plants that break below the
`ear.
`
`TAS BLS = TASSEL BLAST. A | to 9 visual rating was
`used to measure the degree ofblasting (necrosis due to heat
`stress) of the tassel at time of flowering. A 1 would indicate
`a very high level of blasting at time of flowering, while a 9
`would have notassel blasting.
`TAS SZ = TASSELSIZE.A 1 to 9 visual rating was used
`to indicate the relative size of the tassel. The higher the
`rating the larger the tassel.
`TAS WT = TASSEL WEIGHT.Thisis the average weight
`of a tassel (grams) just prior to pollen shed.
`
`

`

`5,463,173
`
`_
`
`5
`TEX EAR = EAR TEXTURE.A 1 to 9 visual rating was
`uscd to indicate the relative hardness (smoothness of crown)
`of mature grain. A 1 would be very soft (extreme dent) while
`a 9 would be very hard (flinty or very smooth crown).
` TILLER=TILLERS.A count of the numberoftillers per
`plot that could possibly shed pollen was taken. Data is given
`as percentage oftillers: numberoftillers per plot divided by
`number of plants perplot.
`TST WT = TEST WEIGHT UNADJUSTED. The mea-
`sure of the weightof the grain in poundsfor a given volume
`(bushel).
`TST WTA = TEST WEIGHT ADJUSTED. The measure
`of the weight of the grain in pounds for a given volume
`(bushel) adjusted for percent moisture.
`YLD = YIELD.It is the same as BU ACR ABS.
`
`YLD SC = YIELD SCORE.A 1 to 9 visual rating was
`used to give a relative rating for yield based on plotear piles.
`The higher the rating the. greater visual yield appearance.
`MDM CPX = Maize Dwarf Mosaic Complex (MDMV-
`Maize Dwarf Mosaic Virus & MCDV = Maize Chlorotic
`Dwarf Virus): Visual rating (1-9 score) where a “1” is very
`susceptible and a “9” is very resistant.
`SLF BLT = Southern Leaf Blight (Bipolaris maydis,
`Helminthosporium maydis). Visual rating (1-9 score) where
`a “1” is very susceptible and a “9” is very resistant.
`NLF BLT = Northern Leaf Blight (Exserohilum turcicum,
`H. turcicum): Visual rating (1-9 score) where a “1” is very
`susceptible and a “9” is very resistant.
`COM RST = Common Rust (Puccinia sorghi): Visual
`rating (1-9 score) where a “1”is very susceptible and a “9”
`is very resistant.
`GLF SPT = Gray Leaf Spot (Cercospora zeae-maydis):
`Visual rating (1-9 score) where a “1”is very susceptible and
`a “9” is very resistant.
`STW WLT = Stewart’s Wilt (Erwinia stewartii): Visual
`rating (1-9 score) where a “1” is very susceptible and a “9”
`is very resistant.
`HD SMT = Head Smut (Spacelotheca reiliana). Percent-
`age of plants that did not have infection.
`EAR MLD= General Ear Mold: Visual rating (1-9 score)
`where a “1” is very susceptible and a “9” is very resistant.
`This is based on overall rating for ear mold of mature ears
`without determining specific mold organism, and may not be
`predictive for a specific ear mold,
`ECB DPE = Dropped ears due to European Cor Borer
`(Ostrinia nubilalis). Percentage of plants that did not drop
`ears under second brood corn borer infestation.
`
`ECB 2SC = European Com Borer Second Brood
`(Ostrinia nubilalis): Visual rating (1-9 score) of post flow-
`ering damage dueto infestation by European Corn Borer. A
`“1” is very susceptible and a “9”is very resistant.
`ECB 1LF = Evropean Corn Borer First Brood (Ostrinia
`nubilalis): Visual rating (1-9 score) of pre-flowering leaf
`feeding by European Corn Borer. A “1” is very susceptible
`and a “9” is very resistant.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`Inbred corn line PHR61 is a yellow, dent corn inbred that
`is best used as a female in crosses for producing first
`generation Fl com hybrids. PHR61 is best adapted to the
`North Central Region of the United States. The inbred can
`be used to produce hybrids from approximately 105-117
`
`15
`
`20
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`30
`
`45
`
`50
`
`55
`
`60
`
`65
`
`6
`relative maturity based on the Minnesota Relative Maturity
`Rating System for harvest moisture of grain. PHR61 has
`consistent high hybrid yields for its grain moisture maturity.
`PHR61 hasexcellent stalks, stay green, and grain quality. It
`has hard textured grain, high test weight, and goodstress
`resistance. PHR61 has high inbred kernel yields, but has
`small kernels and has almost no inbred tassel branches,
`therefore, it does not make a good male. In hybrid combi-
`nations, the ear is medium in height and it has good ear
`retention, but plants are tall. Inbred PHR61 provides hybrids
`which, although adapted to cool Northern climates, perform
`exceptionally well in warm growing seasons which occa-
`sionally occur in the Northern Corn Belt of the United
`States.
`
`The inbred has shown uniformity and stability within the
`limits of environmental
`influence for all
`the traits as
`described in the Variety Description Information (Table 1)
`that follows. Most of the data in the Variety Description
`Information wascollected at Johnston, lowa. The inbred has
`been self-pollinated and ear-rowed a sufficient number of
`generations with careful attention paid to uniformity of plant
`type to ensure homozygousity and phenotypicstability. The
`line has been increased both by hand andin isolated fields
`with continued observation for uniformity. No varianttraits
`have been observedor are expected in PHR61.
`Inbred corn line PHR61, being substantially homozygous,
`can be reproducedbyplanting seedsof the line, growing the
`resulting corn plants under self-pollinating or sib-mating
`conditions with adequateisolation, and harvesting the result-
`ing seed, using techniques familiar to the agricultural arts.
`
`TABLE1
`
`VARIETY DESCRIPTION INFORMATION
`
`INBRED=PHR61
`
`Type: Dent
`
`Region Best Adapted: North Central
`
`A. Maturity: Average across maturity zones. Zone: 0
`Heat Unit Shed: 1470
`Heat Unit Silk: 1490
`
`No. Reps: 54
`
`[Max. Temp. (86° F.) +
`Min. Temp (250° F.)]*
`z
`
`-50
`
`HEATUNITS =
`
`If maximum is greater than 86 degrees fahrenheit, then 86 is used and if
`minimum is less than 50, then 50 is uscd. Heat units accumulated daily and
`can not be less than 0.
`
`B. Plant Characteristics:
`Plant height (to tassel tip): 244 cm
`Length of top ear internode: 12 cm
`Numberof ears per stalk: Single
`Ear height (to base of top ear): 81 cm
`Numberoftillers: None
`Cytoplasm type: Normal
`C. Leaf:
`Color: Medium Green (WF9)
`Angle from Stalk: <30 degrees
`Marginal Waves: Few (WF9)
`Number of Leaves (mature plants): 18
`Sheath Pubescence: Light (W22)
`
`

`

`5,463,173
`
`7
`Longitudinal Creases: Few (OHS6A)
`Length (Ear node leaf): 75 cm
`Width (widest point, ear node leaf): 10 cm
`D. Tassel:
`Numberlateral branches: 1
`Branch Angle from central spike: >45 degrees
`Pollen Shed: Low based on Pollen Yield Test
`Peduncle Length (top leaf to basal branches): 20 cm
`Anther Color: Yellow
`Glume Color: Green
`E. Ear (Husked Ear Data Except When Stated Otherwise):
`Length: 16 cm
`Weight: 112 gm
`Mid-point Diameter: 38 mm
`Silk Color: Green
`Husk Extension (Harvest stage): Medium (Barely cover-
`ing ear)
`Husk Leaf: Short (<8 cm)
`Taper of Ear: Slight
`Position of Shank (dry husks): Upright
`Kernel Rows: Straight, Distinct Number =14
`Husk Color (fresh): Light Green
`Husk Color (dry): Buff
`Shank Length: 13 cm
`Shank (No. of internodes): 8
`F. Kernel (Dried):
`Size (from ear mid-point)
`Length: 10 mm
`Width: 6 mm
`Thick: 4 mm
`Shape Grade (% rounds): < 20 (13 % medium round based
`on Parent Test Data)
`Pericarp Color: Colorless
`Aleurone Color: Homozygous Yellow
`Endosperm Color: Yellow
`Endosperm Type: Normal Starch
`Gm Wt/100 Seeds (unsized): 24 gm
`G. Cob:
`Diameter at mid-point: 20 mm
`Strength: Strong
`Color: Red
`H.Diseases:
`Corn Lethal Necrosis (MCMV=Maize Chlorotic Mottle
`Virus and MDMV=Maize Dwarf Mosaic Virus): Intermedi-
`ate
`Maize Dwarf Mosaic Complex (MDMV & MCDV=
`Maize Dwarf Virus): Susceptible
`Anthracnose Stalk Rot (C. graminicola): Intermediate
`S. Leaf Blight (B. maydis): Intermediate
`N. Leaf Blight (E. turcicum): Intermediate
`Common Rust (P. sorghi): Intermediate
`Southern Rust (P. polysora): Susceptible
`Gray Leaf Spot (C. zeae): Susceptible
`Stewart’s Wilt (Z. stewartii): Susceptible
`Goss’s Wilt (C. nebraskense): Resistant
`Fusarium Ear Mold (F. moniliforme): Resistant
`I. Insects:
`European Com Borer-1 Leaf Damage (Pre-flowering):
`Intermediate
`European Corn Borer-2 (Post-flowering): Intermediate
`The above descriptions are based on a scale of 1-9,
`being highly susceptible, 9 being highly resistant.
`S (Susceptible): Would generally representa score of 1-3.
`I (intermediate): Would generally represent a score of
`4-5.
`R (Resistant): Would generally represent a score of 6-7.
`H (Highly Resistant): Would generally represent a score
`of 8-9. Highly resistant does not
`imply the inbred is
`immune.
`
`1
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`8
`J. Variety Most Closely Resembling:
`
`
` Character Inbred
`
`Maturity
`PHG39
`
`Usage PHG39
`
`PHG39 (PVP Certificate No. 8300115) is a Pioneer Hi-
`Bred International, Inc. proprietary inbred.
`Data for Items B, C, D, E, F, and G are based primarily
`on a maximum of four reps from Johnston, Iowa grown in
`1989 and 1990, plus description information from the main-
`taining station.
`
`ELECTROPHORESIS RESULTS
`
`Isozyme Genotypes for PHR61
`
`Isozyme data were generated for inbred corn line PHR61
`according to the procedures described in Stuber, C. W.,
`Wendel, J. F, Goodman, M. M., and Smith, J. S.C., “Tech-
`niques and Scoring Procedures for Starch Gel Electrophore-
`sis of Enzymes from Maize (Zea mays L.)”, Technical
`Bulletin No. 286, North Carolina Agricultural Research
`Service, North Carolina State University, Raleigh, N.C.
`(1988).
`The data in Table 2 compares PHR61 with its parents,
`G39 and PHG69.
`
`TABLE 2
`
`ELECTROPHORESIS RESULTS FOR PHR61
`AND ITS PARENTS G39 AND PHG69
`
`LOCI
`
`ACP1
`ADHI
`CAT3
`DIA]
`GOT1
`GOT2
`GOT3
`IDH1
`IDH2
`MDHi
`MDH2
`MDH3
`MDH4
`MDH5
`
`PGM1
`PGM2
`PGD1
`PGD2
`PHI
`
`PHR61
`
`raDAADARANANWOAL
`aaaPUNBWOANNA
`
`PARENTS
`
`PHG69
`
`—EABRPRANWOAN
`
`G39
`
`eeePUNBDOANNAAAAALANAWOAH
`
`INDUSTRIAL APPLICABILITY
`
`This invention also is directed to methods for producing
`a corn plant by crossing a first parent corn plant with a
`second parent corn plant wherein the first or second parent
`corn plant is an inbred corn plant from the line PHR61.
`Further, both first and second parent com plants can come
`from the inbred corn line PHR61. Thus, any such methods
`using the inbred corn line PHR61 are part of this invention:
`selfing, backcrosses, hybrid production, crosses to popula-
`tions, and the like. Al! plants produced using inbred corn line
`PHR61 as a parent are within the scope of this invention.
`
`

`

`5,463,173
`
`10
`placement and flowers (GDU Shed and GDU Silk) earlier.
`PHR6]1 hasa significantly smaller tassel, but has better ear
`texture and grain appearance than G39. PHR61 has worse
`stay green, is more susceptible to stalk, and has morebrittle
`stalks than G39. PHR61 has slightly more resistance to ear
`mold and Northern leaf blight, but is more susceptible to
`common rust and second brood European corn borer than
`G39.
`
`9
`Advantageously, the inbred corn line is used in crosses with
`other, different, corn inbreds to producefirst generation (F,)
`corn hybrid seeds and plants with superior characteristics.
`Asused herein, the terms “plant and plant parts” include
`plant cells, plant protoplasts, plant cell tissue culture from
`which com plants can be regenerated, plant calli, plant
`clumps, and plant cells that are intact in plants or parts of
`plants, such as embryos,pollen, flowers, kernels, ears, cobs,
`leaves, husks, stalks, roots, root tips, anthers, silk and the
`like.
`
`Com,including both grain and non-grain portions of the
`plant, is also used extensively as livestock feed, primarily
`for beef cattle, dairy cattle, hogs, and poultry.
`Industrial uses of corn are mainly from corn starch from
`the wet-milling industry and corn flour from the dry-milling
`industry. The industrial applications of corn starch and flour
`are based on functional properties, such as viscosity, film
`formation, adhesive properties, and ability to suspend par-
`ticles. The corn starch and flour have application in the paper
`and textile industries. Other industrial uses include applica-
`tions in adhesives, building materials, foundry binders,
`laundry starches, explosives, oil-well muds, and other min-
`ing applications.
`Plant parts other than the grain of corn are also used in
`industry. Stalks and husks are made into paper and wall-
`board and cobs are used for fuel and to make charcoal.
`
`The seed of inbred corn line PHR61, the plant produced
`from the inbred seed, the hybrid corn plant produced from
`the crossing of the inbred, hybrid seed, and variousparts of
`the hybrid corn plant can be utilized for human food,
`livestock feed, and as a raw material in industry.
`
`Example
`
`Table 3B contains results comparing PHR61 to PHG69.
`PHG69 is the other parent of PHR61. PHR61 and PHG69
`have similar test weight, but PHR61 has higher yield and
`Tissue culture of corn is described in European Patent
`grain harvest moisture. PHR61 is taller with higher ear
`Application, publication 160,390, incorporated hercin by
`placementand flowers (GDU Shed and GDUSilk)later than
`reference. Com tissue culture procedures are also described
`PHG69. PHR61 has better grain appearance, significantly
`in Green and Rhodes,“Plant Regeneration in Tissue Culture
`better stay green, and better resistance to stalk and root
`of Maize,” Maize for Biological Research (Plant Molecular
`lodging than PHG69.
`Biology Association, Charlottsville, Va. 1982, at 367-372)
`Tables 3C through 3F compare PHR61 with other Pioneer
`and in Duncan,et al., “The Production of Callus Capable of
`proprietary inbreds with similar genetic backgrounds, simi-
`Plant Regeneration from Immature Embryos of Numerous
`lar usage and proven performance in the area where PHR6]1
`Zea Mays Genotypes,” 165 Planta 322-332 (1985). Thus,
`is adapted.
`another aspect of this invention is to provide cells which
`upon growth and differentiation produce the inbred line
`Theresults in Table 3C show PHR61 has loweryield and
`PHR61.
`grain harvest moisture, but higher test weight than PHK29.
`PHR61 isaslightly taller plant with lower ear placement and
`Corn is used as human food, livestock feed, and as raw
`flowers (GDU Shed and GDU Silk) earlier compared to
`25
`material in industry. The food uses of corn, in addition to
`PHK29. PHR61 hasbetter seedling vigor and higher early
`human consumption of corn kernels, include both products
`stand count than PHK29. The tassel size of PHR61 is
`of dry- and wet-milling industries. The principal products of
`significantly smaller than PHK29, but PHR61 hasbetter ear
`corm dry milling are grits, meal and flour. The corn wet-
`texture and grain appearance. PHK29 hasbetter stay green
`milling industry can provide corn starch, corn syrups, and
`and root lodging resistance, but PHR61 has better stalk
`dextrose for food use. Corn oil is recovered from corn germ,
`lodging resistance. PHR61 is more susceptible to Stewart's
`which is a by-product of both dry- and wet-milling indus-
`tries.
`wilt and first brood European corn borer, but more resistant
`to Northern and Southern leaf blight than PHK29.
`The results in Table 3D compare PHR61 to PHR47. The
`results show PHR61 has higher yield, grain harvest mois-
`ture, and test weight than PHR47. PHR6] is a taller inbred
`with higher ear placement and flowers (GDU Shed and GDU
`Silk) later than PHR47. PHR61 has a smaller tassel and is
`more susceptible to root lodging, but has better ear texture,
`grain appearance, stay green, and is more resistant to stalk
`lodging and has fewerbrittle stalks than PHR47.
`The results in Table 3E compare PHR61 to PHT10. The
`results show PHR61 is significantly higher yielding, has
`significantly lower moisture at grain harvest, and has sig-
`nificantly higher test weight
`than PHT10. PHR61 and
`PHT10 havesimilar ear height, but PHR61 is a taller inbred
`and flowers (GDU Shed and GDU Silk) earlier. PHR61 has
`significantly better seedling vigor, early stand count, and
`cold test than PHT10. PHR61 has small tassels, good ear
`texture and grain appearance, and fewer brittle stalks, but
`lower stay green and is more susceptible to stalk and root
`lodging than PHT10. PHR61 and PHT10 have similar
`disease and insect resistance, but PHR61 hasbetter Northern
`leaf blight resistance and is more susceptible to Stewart’s
`wilt.
`
`10
`
`20
`
`35
`
`40
`
`45
`
`55
`
`INBRED AND HYBRID PERFORMANCE OF
`PHR61
`
`In the examples that follow, the traits and characteristics
`of inbred corn line PHR61 are given asa line and in hybrid
`combination. The data collected on inbred corn line PHR61
`is presented for the key characteristics and trails.
`Table 3A compares PHR61 to oneof its parents, G39. The
`results show PHR61 and G39 have similar harvest moisture,
`but PHR61 has higher yield and test weight. PHR61 and
`G39 have similar plant height, but PHR61 has lower ear
`
`60
`
`65
`
`Table 3F compares PHR61 to the public inbred B73.
`PHR61 has lower yield and grain harvest moisture, but
`significantly higher test weight than B73. PHR61 is shorter
`with lower ear placement and flowers (GDU Shed and GDU
`Silk) earlier than B73. Compared to B73, PHR61 has better
`seedling vigor, higher early stand count, and better cold test.
`PHR61 has small tassels and better textured ears and grain
`appearance than B73. The root lodging of PHR61 and B73
`are similar, but PHR61 is moreresistant to stalk lodging and
`has fewerbrittle stalks. PHR61] has better ear mold, North-
`erm leaf blight, and first brood European corn borer but is
`more susceptible to Stewart’s wilt and second brood Euro-
`
`

`

`12
`
`5,463,173
`
`11
`pean corm borerresistance than B73.
`Table 4 compares a PHR61 hybrid to Pioneer Brand
`Hybrid 3417. 3417 has a parent in common with the PHR61
`hybrid other than PHR61. 3417 is adapted to much of the
`same area as the PHR61 hybrid. The PHR61 hybrid is
`slightly lower yielding and has lower grain harvest moisture,
`but has significantly better test weight
`than 3417. The
`PHR61 hybrid is taller with higher ear placement and
`flowers (GDU Shed)later than 3417. The grain appearance
`is better, but stay green poorer for the PHR61 hybrid 10
`compared to 3417. The PHR61 hybrid is more susceptible to
`stalk androot lodging, but has fewerbrittle stalks than 3417.
`
`5
`
`TABLE 3A
`
`PAIRED INBRED COMPARISON DATA
`VARIETY #1] = PHR61
`VARIETY #2 = G39
`+= 5% SIG
`
`* = 10% SIG
`
`#= 1% SIG
`
`CLD
`EST
`SDG
`EAR
`PLT
`BAR
`EAR
`YLD
`BU
`BU
`VAR
`ACR
`ACR
`sc
`MST
`5Z
`PLT
`HT
`HT
`VGR
`CNT
`TST
`#
`ABS % MN
`ABS
`ABS
`ABS
`ABS
`ABS
`ABS
`ABS
`ABS
`ABS
`
`TOTAL SUM
`L
`70.4
`113
`5.2
`18.3
`3.6
`95.1
`82.0
`29.5
`3.3
`33.7
`84.8
`2
`49.6
`B
`48
`18.9
`6.3
`85.3
`81.9
`32.5
`5.4
`33.3
`87.2
`Locs
`10
`10
`22
`12
`11
`13
`18
`17
`27
`48
`6
`DIFF
`20.8
`4