EERE
`U$005082992A
`United States Patent 15
`5,082,992
`(11] Patent Number:
`[45] Date of Patent:
`Jan, 21, 1992
`Ambrose etal.
`
`[54]
`
`[75]
`
`INBRED CORN LINE PHP02
`
`Inventors: William B. Ambrose, Algona, Iowa;
`Thomas C. Kevern, Milton, Wis.
`
`[73] Assignee:
`
`Pioneer Hi-Bred International, Inc.,
`Des Moines, Iowa
`
`(21] Appl. No.; 266,428
`
`[22] Filed:
`
`Nov. 1, 1988
`
`[S1]
`
`Umt. CUS vesssssssssssseseseseeen A01H 5/00; AOIH 4/00;
`AO1H 1/00; C12N 5/04
`[52] US. C0. cecsssssssseteesssessseteeen 800/200; 800/250;
`800/DIG.56, 47/58; 47/DIG. 1; 435/240.4;
`435/240.49; 435/240.5
`(58] Field of Search ................0. 800/1, 200, 250, 230,
`800/DIG. 56; 47/58, DIG. 1; 435/240.4,
`240.49
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4,812,600
`
`3/1989 Jensen et al. ccc 800/1
`
`OTHER PUBLICATIONS
`
`Nowacki et al. (1972) Bull. de L’Acad. Polonaise des.
`Science 20 (10): pp. 695-698, Abstract relied on.
`Bates et al. (1974) Dept Grain Sci Kans Londres Mex-
`ico, Cimmyt. Abstract relied on.
`Spragueet al (1977), In/Corn & Cern Improvement, Ed.
`
`Sprague et al., American Soc. Agron. Madison WI. p.
`316.
`
`(1977) Jn/Corn & Corn Improvement, Ed.
`Galinat
`Sprague et al. Ameuon Soc. Agron, Madison WI. pp 1
`& 35.
`Greenet al. (1982), Jn. Maize for Biological Research,
`Ed. Sheridan, pp. 367-372, Plant Mol. Biol. Assoc. U.
`Press N. Dakota.
`Germplasm Resources Information Heterole, (1950) PI
`181989, (1960) PI 262587.
`
`Primary Examiner—Howard J. Locker
`Assistant Examiner—Gary Benzion
`Attorney, Agent, or Firm—Michael J. Roth
`
`ABSTRACT
`[57]
`According to the invention, there is provided an inbred
`corn line, designated PHP02. This invention thus relates
`to the plants and seeds of inbred corn line PHPO2 and to
`methods for producing a corn plant produced bycross-
`ing the inbred line PHPO2 with itself or with another
`corn plant. This invention further relates to hybrid corn
`seeds and plants produced by crossing the inbred line
`PHP0O2 with another corn line or plant and to crosses
`with related species.
`
`8 Claims, No Drawings
`
`Inari Exhibit 1075
`Inari Exhibit 1075
`Inari v. Pioneer
`Inari v. Pioneer
`
`

`

`5,082,992
`
`1
`
`INBRED CORN LINE PHP02
`
`FIELD OF THE INVENTION
`
`2
`a superior inbred (A) (recurrent parent) to a donor
`inbred (nonrecurrent parent), which carries the appro-
`priate gene(s) for the trait in question. The progeny of
`this cross is then mated back to the superior recurrent
`parent (A) followed by selection in the resultant prog-
`eny for the desired trait to be transferred from the non-
`recurrent parent. After five or more backcross genera-
`tions with selection for the desired trait, the progeny
`will be heterozygousfor loci controlling the character-
`istic being transferred, but will be like the superior par-
`ent for most or almost all other genes. The last back-
`cross generation would beselfed to give pure breeding
`progeny for the gene(s) being transferred.
`A single cross hybrid corn variety is the cross of two
`inbred lines, each of which may have one or moredesir-
`able characteristics lacked by the other or which com-
`plement the other. The hybrid progeny ofthefirst gen-
`eration is designated F). In the development of hybrids
`only the F) hybrid plants are sought. The F; hybrid is
`more vigorous than its inbred parents. This hybrid
`vigor, or heterosis, can be manifested in many ways,
`including increased vegetative growth and increased
`yield.
`The development of a hybrid corn variety involves
`three steps: (1) the selection of superior plants from
`various germplasm pools; (2) the selfing of the superior
`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 (F1). During the inbreed-
`ing process the vigor of the lines decreases. Vigor is
`restored when twounrelated inbred lines are crossed to
`produce the hybrid progeny (Fi). An important conse-
`quence of the homozygosity and homogeneity of the
`inbred lines is that the hybrid between any two inbreds
`will always be the same. Oncethe inbredsthat give the
`best hybrid have been identified, the hybrid seed can be
`reproduced indefinitely 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 double
`cross hybrid is produced from four inbred lines crossed
`in pairs (A XB and CXD)and then the two F; hybrids
`are crossed again (A X B)X(C XD). Muchofthe hybrid
`vigor exhibited by F; hybridsis lost in the next genera-
`tion (F2). 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 stable,
`high-yielding corn hybrids that are agronomically
`sound. The reasons for this goal are obvious: to maxi-
`mize the amountof grain produced on the land used and
`to supply food for both animals and humans. To accom-
`plish this goal, the corn breeder must select and develop
`corn plants that have the traits that result in superior
`inbred parental lines for producing hybrids.
`SUMMARYOF THE INVENTION
`
`roy 0
`
`15
`
`Ww0
`
`40
`
`45
`
`This inventionis in the field of corn breeding, specifi-
`cally relating to an inbred corn line designated PHPO2.
`BACKGROUNDOF THE INVENTION
`
`The goal of plant breeding is to combinein a single
`variety/hybrid various desirable traits of the parental
`lines. Forfield crops, these traits may include resistance
`to diseases and insects, tolerance 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
`advantage of the plant’s method ofpollination. A plant
`is self-pollinated if pollen from one floweris transferred
`to the sameor anotherflower of the sameplant. A plant
`is cross-pollinated if the pollen comes from a flower on
`a different plant.
`Plants that have been self-pollinated and selected for
`type for many generations become homozygousatal-
`most all gene loci and produce a uniform population of
`true breeding progeny. A cross between two homozy-
`gous lines produce a uniform population of hybrid
`plants that may be heterozygous for many gene loci. A
`cross of two plants each heterozygous at a numberof
`geneloci will produce a population of hybrid plants that
`differ genetically and will not be uniform.
`Corn plants (Zea mays L.) can be bred by both self-
`pollination and cross-pollination techniques. Corn has
`male flowers, located on the tassel, and female flowers,
`located on the ear, on the same plant. Natural pollina-
`tion 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 devel-
`opment 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 desirable traits from two
`or moreinbred lines or various broad-based sources into
`breeding pools from which new inbred lines are devel-
`oped by selfing and selection of desired phenotypes.
`The new inbredsare crossed with other inbred lines and
`the hybrids from these crosses are evaluated to deter-
`mine which have commercial potential.
`Pedigree breeding starts with the crossing of two
`genotypes, each of which may have one or more desir-
`able characteristics that is lacking in the other or which
`complement the other. If the two original parents do
`not provide all of the desired characteristics, other
`sources can beincluded in the breeding population. In
`the pedigree method, superior plants are selfed and
`selected in successive generations. In the succeeding
`generations the heterozygous condition gives way to
`homogeneouslines as a result of self-pollination and
`selection. Typically in the pedigree method of breeding
`five or more generationsof selfing and selection is prac-
`ticed: Fj —F2; FoF3; F3—F4; FFs, etc.
`Backcrossing can be used to improve an inbredline.
`Backcrossing transfers a specific desirable trait from
`one inbred or source to an inbred that lacks that trait.
`This can be accomplished for example byfirst crossing
`
`65
`
`Accordingto the invention, there is provided a novel
`inbred corn line, designated PHPO02. This invention thus
`relates to the seeds of inbred corn line PHPO2, to the
`plants of inbred corn line PHPO2, and to methods for
`producing a corn plant produced bycrossing the inbred
`line PHPO2 with itself or another corn line. This inven-
`tion further relates to hybrid corn seeds and plants pro-
`
`

`

`3
`duced by crossing the inbred line PHP02 with another
`corn line or a related species.
`DEFINITIONS
`
`In the description and examples that follow, a number
`of terms are used herein. In order to provide a clear and
`consistent understandingof the specification and claims,
`including the scope to be given such terms, the follow-
`ing definitions are provided:
`Predicted RM. This trait, predicted relative maturity
`(RM), for a hybrid is based on the harvest moisture of
`the grain. The relative maturity rating is based on a
`knownset of checks and utilizes standard linear regres-
`sion analyses and is referred to as the Minnesota Rela-
`tive Maturity Rating System.
`MN RM. This represents the Minnesota Relative
`Maturity Rating (MN RM)for the hybrid andis based
`on the harvest moisture of the grain relative to a stan-
`dard set of checks of previously determined MN RM
`rating. Regression analysis is used to compute this rat-
`ing.
`Selection Index. The selection index gives a single
`measure of the hybrid’s worth based on information for
`up to five traits. A corn breeder may utilize his or her
`ownset of traits for the selection index. One ofthetraits
`that is almost always included is yield. The selection
`index data presented in the tables in the specification
`represent the mean value averaged across testing sta-
`tions.
`Yield (Bushels/Acre). The yield in bushels/acre is
`the actual yield of the grain at harvest adjusted to
`15.5% moisture.
`Percent Yield. The percent yield is the yield obtained
`for the hybrid in terms of percent of the mean for the
`experiments in which it was grown.
`Moisture. The moistureis the actual percentage mois-
`ture of the grain at harvest presented in percent of the
`mean for the experiments in which the hybrid was
`grown.
`GDUShed. The GDU is the number of growing
`degree units (GDU)or heat units required for an inbred
`line or hybrid to reach anthesis or pollen shed 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 = (Maa. + Min.) 50
`
`The highest maximum used is 86° F. and the lowest
`minimum used is 50° F,. For each hybrid it takes a cer-
`tain number of GDUsto reach various stages of plant
`development. GDUsare a way of measuring plant ma-
`turity. The data is given in percent of the mean for the
`experiments in which the hybrid was grown.
`Stalk Lodging. This is the percentage of plants that
`do not stalk lodge, i.e., stalk breakage, as measured by
`either natural lodging or pushing the stalks and deter-
`mining the percentageofplants that break off below the
`ear. This is a relative rating of a hybrid to other hybrids
`for standability. The data are given as the percentage of
`the mean for the experiments in which the hybrid was
`grown.
`Root Lodging. The root lodging is the percentage of
`plants that do not root lodge; i.e., those that lean from
`the vertical axis at an approximately 30° angle or
`greater would be counted as root lodged. The data is
`
`10
`
`30
`
`50
`
`55
`
`60
`
`65
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`5,082,992
`
`4
`given in percentage of mean of the experiments in
`which the hybrid was grown.
`Barren Plants. This is the number of the plants per
`plot that were not barren (lack ears). The data is con-
`verted to percent of the mean for the experiments in
`which the hybrid was grown.
`Stay Green. Stay green is the measure of plant health
`near the time of black layer formation (physiological
`maturity). A high score indicates better late-season
`plant health. The data is given in percentage of means of
`the experiments in which the hybrid was grown.
`Test Weight. This is the measure of the weightof the
`grain in poundsfor a given volume (bushel) adjusted for
`percent moisture. The data is given in percentage of
`mean of the experiments in which the hybrid was
`grown.
`Cob Score. The cob scoreis a rating of how well the
`grain is shelled off the cob and how badly the cob is
`broken up going through the combine. This is given as
`a 1 to 9 score with 9 being good. A high score indicates
`that the grain shells off of the cob well, and the cob does
`not break. The data is given in percentage of means of
`the experiments in which the hybrid was grown.
`Grain Quality. This is a 1 to 9 rating for the general
`quality of the shelled grain as it is harvested based on
`the color of the harvested grain, any mold on the grain,
`and any cracked grain. High scores indicate good grain
`quality. The data is given in percentage of mean of the
`experiments in which the hybrid was grown.
`Seedling Vigor. This is the visual rating (1 to 9) of the
`amount of vegetative growth after emergence at
`the
`seedling stage (approximately five leaves). A higher
`score indicates better vigor. The data is given in per-
`centage of mean of the experiments in which the hybrid
`was grown.
`Early Stand Count. This is a measure of the stand
`establishment in the spring and represents the numberof
`plants that emerge on a per-plot basis for the hybrid.
`The data is given in percentage of mean of the experi-
`ments in which the hybrid was grown.
`Plant Height. This is a measure of the height of the
`hybrid from the ground to the tip of the tassel and is
`measured in inches. The data is given in percentage of
`mean of the experiments in which the hybrid was
`grown,
`Ear Height. The ear height is a measure from the
`ground to the top developed ear node attachment and is
`measured in inches. The data is given in percentage of
`means of the experiments in which the hybrid was
`grown.
`Dropped Ears. This is a measure of the number of
`dropped ears per plot and represents the number of
`plants that did not drop ears prior to harvest. The data
`is given in percentage of mean of the experiments in
`which the hybrid was grown.
`Brittle Stalks. This is a measure of the stalk breakage
`near the time of pollination of the hybrids, and is an
`indication of whether a hybrid would snap or break at
`the time of flowering under severe winds. Data are
`presented as percentageofplants that did not snap. The
`data is given in percentage of meansof the experiments
`in which the hybrid was grown.
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`Inbred corn line PHPO2 is a yellowdent corn inbred
`that gives superior characteristics in hybrid combina-
`tion and is an excellent parental line in crosses for pro-
`
`

`

`5,082,992
`
`5
`ducing first generation F1 corn hybrids. PHPO2 was
`developed from the single cross PHG44/PHG29 by
`selfing and using the ear-row pedigree method ofbreed-
`ing. A complete description of the development PHP02
`is given in Table No. 2. Both parents, PHG44 and
`PHG29 (PVP Certificate 8600047) are proprietary in-
`bred lines of Pioneer Hi-Bred International, Incorpo-
`rated. The initial cross between PHG44 and PHG29
`was madeat Johnston, Iowa and the F1 single cross was
`selfed at Homestead, Fla. The F2 population was grown
`at Algona, Iowa and 7 ears were saved out of the popu-
`lation. The F3 progenies were grownat Janesville, Wis.
`and selfing and selection were practiced to develop
`PHP02. Testcrosses were made to inbred testers and
`evaluated by the Janesville Research Station. Based on
`the performance of the line per se and in testcrosses
`PHP02 was then evaluated in hybrid combination and
`as a line per se extensively by Pioneer Research Station
`across the northern Corn Belt.
`Theinbred is adapted over a wide area of the north-
`erm Corn Belt and can be used advantageously in hy-
`brids from approximately 95-114 RM based on the
`Minnesota Relative Maturity Rating System for harvest
`moisture of the grain. PHPQ2is an outstanding female
`and over 162 replications of research testing has aver-
`aged 90 bushels per acre or 126 percent of the experi-
`mental mean. Cold test is very adequate as a female asit
`has averaged 90 percent (103 percent of experimental
`mean) over 26 reps of data. Kernal size outis also very
`good for PHPOQ2 and it has approximately 41 percent of
`the kernals falling in the medium flat category. Al-
`though PHP0Q2’s primary use would be as a female,it is
`also an acceptable male with a little below average
`pollen shed ability. Over 12 reps of date, it has a pollen
`percentage of 92 percent of the mean of 1.28 grams of
`pollen per plant. Under extreme heat and drought
`stress, PHPO2 maytopfire and have sometassel blasting
`(necrosis of top leaves and tassei, respectively). It does
`shed for a fairly short duration and should be plantedat
`higher densities to ensure adequate pollen in the pro-
`duction of hybrid seed corn ifit is used as a male.
`The inbred has shown uniformity andstability within
`the limits of environmental influence for all
`traits as
`described in the Variety Description Information.
`However,the line did show segregation for yellow and
`purple anther color with the first foundation increase.
`Additional ear-to-row selection for yellow anther type
`hasfixed the inbred for yellow anther color. PHP02 has
`been self-poilinated and ear-rowed a sufficient number
`of generations with careful attention to uniformity to
`plant type to ensure homozygousity and phenotypic
`stability. The line has been increased both by hand and
`sibbed in isolated fields with continued observation for
`uniformity. Besides the initial segregation for anther
`color, no variant traits have been observed or are ex-
`pected with PHPO2.
`Inbred corn line PHPO2, being substantially homozy-
`gous, can be reproduced by planting seeds oftheline,
`growingthe resulting corn plants underself-pollinating
`or sibpollinating conditions with adequate isolation, and
`harvesting the resulting seed, using techniques familiar
`to the agriculturalarts.
`The data given in the Variety Description Informa-
`tion (Table 1) was collected primarily at Johnston,
`Iowa.
`
`6
`TABLE1
`PHPO02
`VARIETY DESCRIPTION INFORMATION
`Type:
`Dent
`Region Best Adapated:
`Most Regions
`A. Maturity: Zone 0: Averaged across maturity zones
`INBRED = PHP02
`Heat Unit Shed: 1340
`Heat Unit Silk: 1360
`No. Reps: 67
`HEAT UNITS =
`[Max. Temp. (86° F.) + Min. Temp (250° F.)]*
`5
`
`-
`
`20
`
`mo
`
`9
`
`tm
`
`40
`
`45
`
`65
`
`*If maximum is greater than 86 degress fahrenheit, then
`86 is used and if minimum is less than 50, then 50is
`used. Heat units accumulated daily and can not be less
`than 0.
`Plant Characteristics:
`Plant height (to tassel tip): 203 cm
`Length of top ear innernode: 12 cm
`Numberofears per stalk: Slight two-earred tendency
`Ear height (to base of top ear): 81 cm
`Number oftillers: None
`Cytoplasm type: Normal
`Leaf:
`Color: Medium Green (WF9)
`Angle from Stalk: 30-60°
`Marginal Waves: Few (WF9)
`Number of Leaves (mature plants): 18
`Sheath Pubescence: Light (W22)
`Longitudinal Creases: Absent (OH51)
`Length (Ear nodeleaf): 86 em
`Width (widest point, ear node leaf): 94 mm
`Tassel:
`Numberlateral branches: 16
`Branch Angle from central spike: 30-45°
`Potlen Shed: Medium
`Peduncle Length (top leaf to basal branches): 18 cm
`Anther Color: Yellow - was segregating for purple and
`yellowanther color butfixed for yellow
`Glume Color: Green
`Ear (Husked Ear Data Except When Stated Otherwise):
`Length: 20 cm
`Weight: 127 gm
`Mid-point Diameter: 42 mm
`Silk color: Salmon
`Husk Extension (Harvest stage): Short (ear exposed)
`Husk Leaf: Long >15 cm
`Taper of Ear: Average Taper
`Position of Shank (dry husks): Upright
`Kernel Rows: Distinct, Straight, Number = 16
`Husk Color(fresh): Light Green
`Husk Color (dry): Buff
`Shank Length: 10 cm
`Shank (No. of internades): 6
`Kernel (Dried):
`Size (from ear mid-point)
`Length: 10 mm
`Width: 7 mm
`Thick: 4 mm
`Shape Grade (% rounds): 20-40% based on Parenttest
`Pericarp Color: Colorless
`Aleurone Color: Homozygous yellow
`Endosperm Color: Yellow
`Endosperm Type: Normal
`Gm Wt/100 Seeds (unsized): 26 gm
`Cob:
`Diameter at mid-point: 25 mm
`Strength: Strong
`Color: Red
`Diseases:
`Northern Leaf Blight: Susceptible
`Goss’ Bacteria Blight: Intermediate
`Southern Leaf Blight: Susceptible
`Head Smut: Susceptible
`Common Smut: Resistant
`Stewart's Bacterial Wilt: Susceptible
`Corn Lethal Necrosis: Susceptible
`Northern Leaf Spot: Susceptible
`Common Rust: Resistant
`Eye Spot: Intermediate
`
`

`

`5,082,992
`
`8
`TABLE3-continued
`Electrophoresis results for PHPO2 and its parents PHG44
`and PHG29.
`Alleles Present
`Locus
`PHP02
`PHG44
`PHG29
`
`Pgml
`9
`9
`9
`Pgm2
`4
`4
`4
`Pgdl
`3.8
`3.8
`3.8
`5
`Pgd2
`5
`5
`
`4
`Phil
`4
`4
`10
`NO. PLANTS
`10
`10
`*PHG44 had slower migration at Mdh2locus than 3.5 control genotype.
`
`7
`TABLE 1-continued
`PHP02
`VARIETY DESCRIPTION INFORMATION
`Type:
`Dent
`Region Best Adapated:
`Most Regions
`Gray Leaf Spot: Susceptible
`Fusarium Ear Rot: Susceptible
`Insects:
`European Corn Borer: Susceptible
`J. Variety Most Closely Resembling:
`Character
`Inbred
`Maturity
`PHG29
`Plant Type
`PHG29
`Ear Type
`PHG29
`Kernel Type
`PHG29
`Usage
`PHG29
`
`I.
`
`Inbred corn line PHP02 most closely resembles
`PHG29 in characteristics of maturity, plant type, ear
`type, kernal type, and usage.
`TABLE2
`BREEDING HISTORYFOR PHP02
`
`Season/
`Year
`Sum/1979
`Win/1979
`Sum/1980
`Sum/1981
`Sum/1982
`Sum/1983
`Sum/1984
`Sum/1985
`Sum/1986
`Win/1986
`Sum/1987
`Sum/1987
`
`Level Pedigree Grown
`PHG44-PHG29 (cross was made)
`PHG44/PHG29
`PHG44/PHG29)X
`PHG44/PHG29)X1
`PHG44/PHG29)X 12
`PHG44/PHG29)X121
`PHG44/PHG29}X1211
`~=PHP02-1
`PHPO2-1-9
`PHPO02-1-9-(1-10)
`PHPO02-1-9-(1-10)-X
`PHP02-1-9-(1-10)
`
`F)
`F2.
`F3.
`F4
`FS
`Fo
`F7
`F8
`F9
`F110
`FQ
`
`Ears
`Saved
`Bulk
`Bulk
`7
`2
`I
`3
`10
`10
`10
`Bulk
`
`Electrophoresis Results
`Isozyme Genotypes for PHP02
`Isozyme data was generated for inbred corn line
`PHP02 according to the procedure described in Good-
`man, M. M. and Stuber, C. M., “Genetic identification
`of lines and crosses using isoenzyme electrophoresis,”
`Proceeding of the Thirty-Fifth Annual Corn and Sor-
`ghum Industry Research Conference, Chicago,
`II].
`(1980).
`Electrophoresis results comparing PHP02to its par-
`ents, PHG44 and PHG29 are given in Table No. 3.
`These results provide additional support to the pedigree
`for PHPO2.
`
`TABLE3
`Electrophoresis results for PHPO2 andits parents PHG44
`and PHG29.
`Alleles Present
`PHG44
`
`Locus
`
`Acpl
`Adhi
`Cat3
`Dial
`Glul
`Gotl
`Got2
`Got3
`Idh}
`Idh2
`Mdh!
`Mdh2
`Mdh3
`Mdh4
`Mdhs5
`Mmm
`
`PHP02
`
`JRRALPARRERARAWOEN in
`
`ROARAWARRADRADRWOAN
`
`*
`
`wr
`
`15
`
`20
`
`30
`
`35
`
`45
`
`50
`
`55
`
`INDUSTRIAL APPLICABILITY
`
`This inventionalso is directed to methods for produc-
`ing 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 PHPO2. Further, both first and second parent
`corn plants may be from the inbred corn line PHPO2.
`Thus, any methods using the inbred corn line PHP0O2
`are part of this invention: selfing, backcrosses, hybrid
`production, crosses to populations, etc. Any plants pro-
`duced using inbred corn line PHPOQ2 as a parent are
`within the scopeofthis invention. Advantageously, the
`inbred corn line is used in crosses with other corn in-
`breds to producefirst generation (F;) corn hybrid seeds
`and plants with superior characteristics.
`As used herein, the terms “plant and plant parts”
`include plant cells, plant protoplasts, plant cell tissue
`culture from which corn plants can be regenerated,
`plantcalli, plant clumps, and plantcells that are intact in
`plants or parts of plants, such as embryos, pollen, flow-
`ers, kernels, ears, cobs, leaves, husks, stalks, roots, root
`tips, anthers, silk and the like.
`Tissue culture of corn is described in European Pa-
`tent Application, publication 160,390,
`incorporated
`herein by reference. Corn tissue culture procedures are
`also described in Green and Rhodes, ‘‘Plant Regenera-
`tion in Tissue Culture of Maize,” Maize for Biological
`Research (Plant Molecular Biology Association, Char-
`lottsville, Wa. 1982, at 367-372. Thus, another aspect of
`this invention is to provide for cells which upon growth
`and differentiation produce the inbred line PHPO2.
`The utility of inbred line PHPO2 also extends to
`crosses with other species. Commonly, suitable species
`will be of the family Graminaceae, and especially of the
`genera Zea, Tripsacum, Coix, Schlerachne, Polytoca,
`Chinonachne, and Trilobachne, of the tribe Maydeae. Of
`these, Zea and Tripsacum, are most preferred. Poten-
`tially suitable for crosses with PHPOQ2 maybethe vari-
`ous varieties of grain sorghum, Sorghum bicolor (L.)
`Moench.
`Corn is used as human food, livestock feed, and as
`raw material in industry. The food uses of corn, in addi-
`tion to human consumption of corn kernels,
`include
`both products of dry- and wet-milling industries. The
`principal products of corn dry milling are grits, meal
`and flour. The corn wet-milling industry can provide
`corn starch, corn syrups, and dextrose for food use.
`Corn oi] is recovered from corn germ, which is a by-
`product of both dry- and wet-milling industries.
`Corn, including both grain and non-grain portions of
`the plant,
`is also used extensively as livestock feed,
`primarily for beefcattle, dairy cattle, hogs, and poultry.
`Industria] uses of corn are mainly from corn starch
`from the wet-milling industry and corn flour from the
`
`ta
`
`65
`
`PHG29
`
`
`
`NNDWADHEEAEHOWEL
`
`

`

`No. of Reps
`
`5,082,992
`
`~
`
`9
`10
`istics make PHPO2 a very important inbred for produc-
`dry-milling industry. The industrial applications of corn
`starch andflour are based on functional properties, such
`ing commercial single cross hybrids.
`TABLE4
`Average inbred by tester performance comparing PHP02 to PHG29 crossed
`to the same inbred testers and grown in the same experiments. All
`values are expressed as percent of the experiment mean except Predicted
`RM, Selection Index, and Yield (Bu./Ac.).
`PREDICTED
`SELECTION
`YIELD
`PERCENT
`GDU
`STALK
`
`HYBRID
`RM
`INDEX
`(BU./AC.)}
`YIELD MOISTURE SHED
`LODGING
`281
`279
`279
`279
`281
`60
`269
`PHG29 Crosses
`108
`100
`144
`101
`101
`100
`98
`PHP02 Crosses
`108
`104
`147
`103
`101
`98
`103
`Difference
`0
`4
`3
`2
`0
`2
`5
`
`EARLY
`ROOT
`BARREN
`STAY
`TEST
`COB
`GRAIN
`SEEDLING STAND
`
`HYBRID
`LODGING
`PLANTS
`GREEN WEIGHT
`SCORE QUALITY
`VIGOR
`COUNT
`No.of Reps
`96
`27
`171
`281
`30
`180
`107
`188
`PHG29 Crosses
`103
`100
`92
`100
`93
`100
`102
`102
`PHP02 Crosses
`100
`100
`101
`98
`87
`95
`108
`102
`Difference
`3
`0
`2
`6
`5
`6
`0
`
`HYBRID
`PLANT HEIGHT EAR HEIGHT DROPPED EARS
`BRITTLE STALKS
`
`No. of Reps
`145
`145
`247
`44
`PHG29 Crosses
`100
`99
`100
`100
`PHP0O2 Crosses
`101
`98
`99
`99
`Difference
`1
`1
`1
`1
`
`
`Deposits
`as viscosity, film formation, adhesive properties, and ,,
`Applicants have made available to the public without
`ability to puspend particles. The vd1 Starchand flour
`restriction a deposit of at
`least 2500 seeds of inbred
`Othe a Neal int al Mear lk texte adhenives
` PHPO2 with the American Type Culture Collection
`Regie atdalefoeadee LietoIndy stacker,
`(ATCC), Rockville, Md. 20852 USA, ATCC Deposit
`sol ing mate ait vad ry 4 the auncry s ol ©
`explosives, oll-well muds,
`and
`other mining applica- 39 No. 75077. The seeds deposited with the ATCC are
`Toe
`her
`than
`th
`in
`of
`1
`4
`taken from the same deposit maintained by Pioneer
`a on eaeerilkea a iene ch are also use§
`_Hi-Bred International Inc., 700 Capital Square, 400
`in Ib ne he he a usQforfi ied edie ke« ha
`Locust Street, Des Moines, Iowa 50309 since prior to
`voal oar
`and cobs are used
`for
`fel
`ane
`to make char-
`the filing date of this application. The deposit will be
`coal.
`35 maintained in the ATCC depository, whichis a public
`The seed of inbred corn line PHP02, the plant pro-
`depository, for a period of 30 years, or 5 years after the
`duced from the inbred seed, the hybrid corn plant pro-
`most recent request, or for the effective life of the pa-
`duced from the crossing of the inbred, hybrid seed, and
`tent, whichever is longer, and will be replaced if it
`various parts of the hybrid corn plant can be utilized for
`becomes nonviable during that period.
`human food, livestock feed, and as a raw material in
`Whatis claimedis:
`mdustry.
`1. Inbred corn seed designated PHP02 having ATCC
`accession No.
`2. A corn plant produced by the seed of claim 1.
`3. Tissue culture of the plant of claim 2.
`4. Tissue culture according to claim 3 comprising
`regenerable cells of a plant part selected from meriste-
`matic tissue, anthers, leaves, embryos, protoplasts, and
`pollen.
`5. A corn plant regenerated from regenerablecells of
`a tissue culture according to claim 4.
`6. An inbred corn plant having all the physiological
`and morphological characteristics of the seed of claim
`1
`
`EXAMPLE
`
`Hybrid Performance of PHP02
`
`In the examples that follow, the key traits and charac-
`teristics of inbred corn line PHPO2 are given for some of
`its hybrid combinations.
`The data in Table No. 4 gives a comparison of PHP02
`to PHG29 crossed to the sametester lines and the hy-
`brids evaluated in the same experiments at the same
`locations. Both inbreds were crossed to the same seven
`lines and evaluated in the Eastern, Northern, Central,
`and Western Regionsand the data presentedis the over-
`all summary and has 279 replications of data averaged
`over testers and locations for yield. PHPO2 is similar
`genetically to PHG29 but does show somesignificant
`advantages. Its hybrids tend to havea little higheryield,
`are earlier to flower, and are a little better agronomi-
`cally for stalk lodging resistance and staygreen charac-
`teristics. PHP02 hybrids do tend to have lowertest
`weight and a little poorer grain quality than PHG29
`crosses. Other attributes tend to be very similar.
`Drought tolerance of PHPO2 hybrids have tended to be
`a little poorer than PHG29 crosses based on research
`testing. PHP02 crosses can be susceptible to ear molds
`and its use in areas of extreme ear mold pressure should
`be limited. However, the overall] performance of the
`line in hybrid combination as well as the outstanding
`female parental and acceptable male parental character-
`
`40
`
`45
`
`7. A method to produce a novel hybrid corn seed
`comprising the steps of:
`a) planting in pollinating proximity seeds of corn
`inbred lines PHP02 and anotherinbredline;
`b) cultivating corn plants resulting from said planting
`until the time the plants bear flowers,
`c) emasculating the flowers of the plants of either
`inbred line;
`d) allowing natural cross pollinating to occur be-
`tween said inbred lines; and
`e) harvesting seed produced on said emasculated
`plants of the inbred line.
`8. An F, hybrid corn plant and seed thereof produced
`by crossing an inbred corn plant according to claim 2
`with another, different corn plant.
`*
`*
`*
`*
`*
`
`65
`
`

`

`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`
`PATENTNO.
`
`- 5,082,992
`
`DATED
`
`: January 21, 1992
`
`INVENTOR(S) : William B. Ambrose, et al.
`
`It is certified that error appears in the above-identified patent and that said Letters Patert is hereby
`corrected as shown below:
`
`
`
`At Column
`| --Stations--.
`
`5,
`
`Line
`
`19,
`
`please
`.
`
`rewrite "Station"
`
`as
`
`At Column 5, Line 36, please rewrite "of" as --to--,
`At Column 7, Line 29,
`after Line Sum/1984, please rewrite
`“PHG44/PHG29}X1211 as --PHG44/PHG29)X1211--.
`At Column 8, Line
`43,
`please rewrite "Charlottsville" as
`-~-Charlottesville-—-.
`
`
`
`At Column
`| --75077--.
`
`|
`
`|
`
`10, Line
`
`42,
`
`following
`
`"No."
`
`please insert
`
`Signed and Sealed this
`Sixth Dayof July, 1993
`
`DYeckael nr Rok
`
`MICHAEL K. KIRK
`
`Attest:
`
`Attesting Officer
`
`Acting Commissioner of Putents and Trademarks
`
`
`
`