Plants and seeds of corn variety 1294213 Number:7,521,609 from the United States Patent and Trademark Office (PTO) owispatent According to the invention, there is provided seed and plants of the corn variety designated I294213. This invention thus relates to the plants, seeds and tissue cultures of the variety I294213, and to methods for producing a corn plant produced by crossing a corn plant of variety I294213 with itself or with another corn plant, such as a plant of another variety. This invention further relates to corn seeds and plants produced by crossing plants of variety I294213 with plants of another variety, such as another inbred line, and to crosses with related species. This invention further relates to the inbred and hybrid genetic complements of plants of variety I294213, and also to the SSR profiles of corn variety I294213.<H 1294213, variety, Plants, and, seed, 7521609.html, Patent, pto, 7521609

Title: Plants and seeds of corn variety 1294213

Abstract: According to the invention, there is provided seed and plants of the corn variety designated I294213. This invention thus relates to the plants, seeds and tissue cultures of the variety I294213, and to methods for producing a corn plant produced by crossing a corn plant of variety I294213 with itself or with another corn plant, such as a plant of another variety. This invention further relates to corn seeds and plants produced by crossing plants of variety I294213 with plants of another variety, such as another inbred line, and to crosses with related species. This invention further relates to the inbred and hybrid genetic complements of plants of variety I294213, and also to the SSR profiles of corn variety I294213.

Patent Number: 7,521,609 Issued on 04/21/2009 to Hall, et al.

Inventors: Hall; Michael A. (Sycamore, IL), Cook; Vanessa M. (Spencer, IA)
Assignee: Monsanto Technology LLC (St. Louis, MO)

Appl. No.: 11/626,268

Filed: January 23, 2007

Related U.S. Patent Documents


Application Number	Filing Date	Patent Number	Issue Date
10384358	Mar., 2003	7166779

Current U.S. Class: 800/320.1 ; 800/275; 800/300.1; 800/301; 800/302; 800/303

Current International Class: A01H 5/00 (20060101); A01H 5/10 (20060101); A01H 1/02 (20060101)

References Cited [Referenced By]

U.S. Patent Documents


4517763	May 1985	Beversdorf et al.
4658084	April 1987	Beversdorf et al.
4658085	April 1987	Beversdorf et al.
4677246	June 1987	Armond et al.
4731499	March 1988	Puskaric et al.
5276263	January 1994	Foley

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Duvick, "Genetic contributions to yield gains of U.S. hybrid maize, 1930 to 1980," Genetic Contributions to Yield Gains of Five Major Crop Plants: Proceedings of a Symposium sponsored by Div. C-1, Crop Science Society of America, Dec. 2, 1981 in Atlanta, Georgia; W.R. Fehr, Crop Science Society of America and American Society of Agronomy, Madison, Wisconsin, pp. 15-47. cited by other .
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Hallauer et al., "Corn Breeding," In: Corn and Corn Improvement, Sprague et al. (eds.)., Madison, Wisconsin, Ch. 8, pp. 463-564, 1988. cited by other .
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Meghji et al., "Inbreeding depression, inbred and hybrid grain yields, and other traits of maize genotypes representing three eras," Crop Science, 24:545-549, 1984. cited by other .
Poehlman et al., Breeding Field Crops, 4.sup.th edition, Iowa State University Press, Ames, IA, pp. 172-175, 1995. cited by other .
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Rieger et al., Glossary of Genetics and Cytogenetics, Classical and Molecular, Springer-Verlag, Berlin, p. 116, 1976. cited by other .
Sprague et al., "Corn Breeding," In: Corn and Corn Improvements, Sprague (ed.), No. 18 in Agronomy Series, American Society of Agronomy, Inc., Madison, Wisconsin, Ch. 6, pp. 305-323, 1977. cited by other .
Troyer, "A retrospective view of corn genetic resources," Journal of Heredity, 81:17-24, 1990. cited by other .
Wych, "Production of hybrid seed corn," In: Corn and Corn Improvement, Sprague et al.(eds.), Madison, Wisconsin, Ch. 9, pp. 567-607, 1988. cited by other.

Primary Examiner: Fox; David T
Attorney, Agent or Firm: Sonnenschein Nath & Rosenthal LLP

Parent Case Text

This application is a continuation application of application Ser. No. 10/384,358, filed Mar. 7, 2003, now U.S. Pat. No. 7,166,779, the entire disclosure of which is specifically incorporated herein by reference.

Claims

What is claimed is:

1. A hybrid corn seed having a male parent and a female parent, wherein the male and female parents each comprise a diploid genome having a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, each parent further being homozygous with respect to each allele pair; the hybrid corn seed also comprising a diploid genome having a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, one of the alleles being contributed by the male parent and the other being contributed by the female parent, wherein one of the parents is a plant of the corn variety I294213, a sample of the seed of said corn variety I294213 having been deposited under ATCC Accession PTA-7859, and wherein the other parent is a plant of a different variety; whereby one allele at each locus in the hybrid genome consists essentially of the allele found at the same locus in corn variety I294213, and further whereby the other allele in a plurality of such loci in the hybrid genome is different from the allele found at the same locus in corn variety I294213.

2. A corn plant grown from the seed of claim 1.

3. The hybrid corn seed of claim 1, wherein the plant of corn variety I294213 further comprises a transgene introduced by genetic transformation.

4. The hybrid corn seed of claim 3, wherein the transgene confers a trait selected from the group consisting of herbicide tolerance; insect resistance; resistance to bacterial, fungal, nematode or viral disease; waxy starch; male sterility and restoration of male fertility.

5. The hybrid corn seed of claim 1, wherein the plant of corn variety I294213 further comprises a conversion of the I294213 parent to express at least one new trait, wherein the conversion was produced by a method comprising the steps of: (a) crossing a first corn plant having a first diploid genome comprising a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, and further comprising a genetic locus that confers at least one new trait, with a second plant of the corn variety I294213, a sample of the seed of the corn variety I294213 having been deposited under ATCC Accession PTA-7859, the plant of the corn variety I294213 having a second diploid genome comprising a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, to produce seed comprising a diploid genome having a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, wherein one of the alleles is contributed by the first corn plant and the other is contributed by the plant of the corn variety I294213, said genome further comprising the genetic locus that confers the new trait; (b) harvesting and planting the seed thereby produced to produce at least one progeny plant of the first filial generation, said progeny plant comprising a diploid genome comprising the genetic locus; (c) crossing said progeny plant with a plant of the corn variety I294213 to produce seed of a subsequent filial generation, the seed comprising a diploid genome having a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, wherein one of the alleles is contributed by the progeny plant and the other is contributed by the plant of the corn variety I294213, and further comprising the genetic locus that confers the new trait; (d) growing at least one progeny plant of the subsequent filial generation from the seed produced in step (c), said progeny plant comprising a genome comprising the genetic locus that confers the new trait; (e) repeating steps (c) and (d) for at least three additional generations to produce a convened plant of the corn variety I294213 wherein the plant comprises a diploid genome having a plurality of paired chromosomes comprising a plurality of mappable genetic loci with a pair of alleles at each locus, wherein both alleles at substantially all of the loci consist essentially of the allele found at the same locus in corn variety I294213, the genome further comprising the genetic locus that confers the new trait; and (f) harvesting the seed of the converted plant.

6. The hybrid corn seed of claim 5, wherein the genetic locus was conferred by a transgene.

7. The hybrid corn seed of claim 5, wherein the genetic locus is selected from the group consisting of a dominant allele and a recessive allele.

8. The hybrid corn seed of claim 5, wherein the new trait is selected from the group consisting of herbicide tolerance; insect resistance; resistance to bacterial, fungal, nematode or viral disease; waxy starch; male sterility and restoration of male fertility.

9. A corn plant grown from the seed of claim 3.

10. A corn plant grown from the seed of claim 5.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of corn breeding. In particular, the invention relates to inbred corn seed and plants of the variety designated I294213, and derivatives and tissue cultures thereof.

2. Description of Related Art

The goal of field crop breeding is to combine various desirable traits in a single variety/hybrid. Such desirable traits include greater yield, better stalks, better roots, resistance to insecticides, herbicides, pests, and disease, tolerance to heat and drought, reduced time to crop maturity, better agronomic quality, higher nutritional value, and uniformity in germination times, stand establishment, growth rate, maturity, and fruit size.

Breeding techniques take advantage of a plant's method of pollination. There are two general methods of pollination: a plant self-pollinates if pollen from one flower is transferred to the same or another flower of the same plant. A plant cross-pollinates if pollen comes to it from a flower on a different plant.

Corn plants (Zea mays L.) can be bred by both self-pollination and cross-pollination. Both types of pollination involve the corn plant's flowers. Corn has separate 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 ear shoot.

Plants that have been self-pollinated and selected for type over many generations become homozygous at almost all gene loci and produce a uniform population of true breeding progeny, a homozygous plant. A cross between two such homozygous plants produces a uniform population of hybrid plants that are heterozygous for many gene loci. Conversely, a cross of two plants each heterozygous at a number of loci produces a population of hybrid plants that differ genetically and are not uniform. The resulting non-uniformity makes performance unpredictable.

The development of uniform corn plant hybrids requires the development of homozygous inbred plants, the crossing of these inbred plants, and the evaluation of the crosses. Pedigree breeding and recurrent selection are examples of breeding methods used to develop inbred plants from breeding populations. Those breeding methods combine the genetic backgrounds from two or more inbred plants or various other broad-based sources into breeding pools from which new inbred plants are developed by selfing and selection of desired phenotypes. The new inbreds are crossed with other inbred plants and the hybrids from these crosses are evaluated to determine which of those have commercial potential.

The pedigree breeding method involves crossing two genotypes. Each genotype can have one or more desirable characteristics lacking in the other; or, each genotype can complement the other. If the two original parental genotypes do not provide all of the desired characteristics, other genotypes can be included in the breeding population. Superior plants that are the products of these crosses are selfed and selected in successive generations. Each succeeding generation becomes more homogeneous as a result of self-pollination and selection. Typically, this method of breeding involves five or more generations of selfing and selection: S.sub.1.fwdarw.S.sub.2; S.sub.2.fwdarw.S.sub.3; S.sub.3.fwdarw.S.sub.4; S.sub.4.fwdarw.S.sub.5, etc. After at least five generations, the inbred plant is considered genetically pure.

Backcrossing can also be used to improve an inbred plant. Backcrossing transfers a specific desirable trait from one inbred or non-inbred source to 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 locus or loci for the trait in question. The progeny of this cross are then mated back to 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 generations with selection for the desired trait, the progeny are heterozygous for loci controlling the characteristic being transferred, but are like the superior parent for most or almost all other loci. The last backcross generation would be selfed to give pure breeding progeny for the trait being transferred.

A single cross hybrid corn variety is the cross of two inbred plants, each of which has a genotype which complements the genotype of the other. The hybrid progeny of the first generation is designated F.sub.1. Typically, F.sub.1 hybrids are more vigorous than their inbred parents. This hybrid vigor, or heterosis, is manifested in many polygenic traits, including markedly improved yields, better stalks, better roots, better uniformity and better insect and disease resistance. In the development of hybrids only the F.sub.1 hybrid plants are typically sought. An F.sub.1 single cross hybrid is produced when two inbred plants are crossed. A double cross hybrid is produced from four inbred plants crossed in pairs (A.times.B and C.times.D) and then the two F.sub.1 hybrids are crossed again (A.times.B).times.(C.times.D).

The development of 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 plants, which, although different from each other, each breed true and are highly uniform; and (3) crossing the selected inbred plants with unrelated inbred plants to produce the hybrid progeny (F.sub.1). During the inbreeding process in corn, the vigor of the plants decreases. Vigor is restored when two unrelated inbred plants are crossed to produce the hybrid progeny (F.sub.1). An important consequence of the homozygosity and homogeneity of the inbred plants is that the hybrid between any two inbreds is always the same. Once the inbreds that give a superior hybrid have been identified, hybrid seed can be reproduced indefinitely as long as the homogeneity of the inbred parents is maintained. Conversely, much of the hybrid vigor exhibited by F.sub.1 hybrids is lost in the next generation (F.sub.2). Consequently, seed from hybrid varieties is not used for planting stock. It is not generally beneficial for farmers to save seed of F.sub.1 hybrids. Rather, farmers purchase F.sub.1 hybrid seed for planting every year.

North American farmers plant tens of millions of acres of corn at the present time and there are extensive national and international commercial corn breeding programs. A continuing goal of these corn breeding programs is to develop corn hybrids that are based on stable inbred plants and have one or more desirable characteristics. To accomplish this goal, the corn breeder must select and develop superior inbred parental plants.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a corn plant of the variety designated I294213. Also provided are corn plants having all the physiological and morphological characteristics of the inbred corn variety I294213. The inbred corn plant of the invention may further comprise, or have, a cytoplasmic or nuclear factor that is capable of conferring male sterility or otherwise preventing self-pollination, such as by self-incompatibility. Parts of the corn plant of the present invention are also provided, for example, pollen obtained from an inbred plant and an ovule of the inbred plant.

The invention also concerns seed of the inbred corn variety I294213. The inbred corn seed of the invention may be provided as an essentially homogeneous population of inbred corn seed of the variety designated I294213. Essentially homogeneous populations of inbred seed are those that consist essentially of the particular inbred seed, and are generally free from substantial numbers of other seed, so that the inbred seed forms between about 90% and about 100% of the total seed, and preferably, between about 95% and about 100% of the total seed. Most preferably, an essentially homogeneous population of inbred corn seed will contain between about 98.5%, 99%, 99.5% and about 99.9% of inbred seed, as measured by seed grow outs. This corresponds to current commercial practice among the leading companies in the seed industry.

Therefore, in the practice of the present invention, inbred seed generally forms at least about 97% of the total seed. However, even if a population of inbred corn seed was found, for some reason, to contain about 50%, or even about 20% or 15% of inbred seed, this would still be distinguished from the small fraction (generally less than 2% and preferably less than 1%) of inbred seed that may be found within a population of hybrid seed, e.g., within a commercial bag of hybrid seed. In such a bag of hybrid seed offered for sale, Federal regulations require that the hybrid seed be at least about 95% of the total seed, or be labeled as a mixture. In the most preferred practice of the invention, the female inbred seed that may be found within a bag of hybrid seed will be about 1% of the total seed, or less, and the male inbred seed that may be found within a bag of hybrid seed will be negligible, i.e., will be on the order of about a maximum of 1 per 100,000, and usually less than this value.

The population of inbred corn seed of the invention can further be particularly defined as being essentially free from hybrid seed. The inbred seed population may be separately grown to provide an essentially homogeneous population of inbred corn plants designated I294213.

In another aspect of the invention, a conversion of the corn variety I294213 is provided that expresses at least one new trait. The conversion may comprise a genetic locus that is a dominant or recessive allele. In certain embodiments of the invention, the genetic locus confers one or more traits such as, for example, male sterility, yield stability, waxy starch, yield enhancement, industrial usage, herbicide resistance, insect resistance, resistance to bacterial, fungal, nematode or viral disease, male fertility, and enhanced nutritional quality. The genetic locus may be a naturally occurring maize gene introduced into the genome of the variety by backcrossing, a natural or induced mutation, or a transgene introduced through genetic transformation techniques. When introduced through transformation, a genetic locus may comprise one or more transgenes integrated at a single chromosomal location.

In yet another aspect of the invention, an inbred corn plant of the variety designated I294213 is provided, wherein a cytoplasmically-inherited trait has been introduced into said inbred plant. Such cytoplasmically-inherited traits are passed to progeny through the female parent in a particular cross. An exemplary cytoplasmically-inherited trait is the male sterility trait. Cytoplasmic-male sterility (CMS) is a pollen abortion phenomenon determined by the interaction between the genes in the cytoplasm and the nucleus. Alteration in the mitochondrial genome and the lack of restorer genes in the nucleus will lead to pollen abortion. With either a normal cytoplasm or the presence of restorer gene(s) in the nucleus, the plant will produce pollen normally. A CMS plant can be pollinated by a maintainer version of the same variety, which has a normal cytoplasm but lacks the restorer gene(s) in the nucleus, and continue to be male sterile in the next generation. The male fertility of a CMS plant can be restored by a restorer version of the same variety, which must have the restorer gene(s) in the nucleus. With the restorer gene(s) in the nucleus, the offspring of the male-sterile plant can produce normal pollen grains and propagate. A cytoplasmically inherited trait may be a naturally occurring maize trait or a trait introduced through genetic transformation techniques.

In another aspect of the invention, a tissue culture of regenerable cells of a plant of variety I294213 is provided. The tissue culture will preferably be capable of regenerating plants capable of expressing all of the physiological and morphological characteristics of the variety, and of regenerating plants having substantially the same genotype as other plants of the variety. Examples of some of the physiological and morphological characteristics of the variety I294213 include characteristics related to yield, maturity, and kernel quality, each of which is specifically disclosed herein. The regenerable cells in such tissue cultures will preferably be derived from embryos, meristematic cells, immature tassels, microspores, pollen, leaves, anthers, roots, root tips, silk, flowers, kernels, ears, cobs, husks, or stalks, or from callus or protoplasts derived from those tissues. Still further, the present invention provides corn plants regenerated from the tissue cultures of the invention, the plants having all the physiological and morphological characteristics of variety I294213.

In yet another aspect of the invention, processes are provided for producing corn seeds or plants, which processes generally comprise crossing a first parent corn plant with a second parent corn plant, wherein at least one of the first or second parent corn plants is a plant of the variety designated I294213. These processes may be further exemplified as processes for preparing hybrid corn seed or plants, wherein a first inbred corn plant is crossed with a second corn plant of a different, distinct variety to provide a hybrid that has, as one of its parents, the inbred corn plant variety I294213. In these processes, crossing will result in the production of seed. The seed production occurs regardless of whether the seed is collected or not.

In a preferred embodiment of the invention, the first step in "crossing" comprises planting, preferably in pollinating proximity, seeds of a first and second parent corn plant, and preferably, seeds of a first inbred corn plant and a second, distinct inbred corn plant. Where the plants are not in pollinating proximity, pollination can nevertheless be accomplished by transferring a pollen or tassel bag from one plant to the other as described below.

A second step comprises cultivating or growing the seeds of said first and second parent corn plants into plants that bear flowers. Corn bears both male flowers (tassels) and female flowers (silks) in separate anatomical structures on the same plant.

A third step comprises preventing self-pollination of the plants, i.e., preventing the silks of a plant from being fertilized by any plant of the same variety, including the same plant. This is preferably done by emasculating the male flowers of the first or second parent corn plant, (i.e., treating or manipulating the flowers so as to prevent pollen production, in order to produce an emasculated parent corn plant), Self-incompatibility systems are also used in some hybrid crops for the same purpose. Self-incompatible plants still shed viable pollen and can pollinate plants of other varieties but are incapable of pollinating themselves or other plants of the same variety.

A fourth step comprises allowing cross-pollination to occur between the first and second parent corn plants. When the plants are not in pollinating proximity, this is done by placing a bag, usually paper or glassine, over the tassels of the first plant and another bag over the silks of the incipient ear on the second plant. The bags are left in place for at least 24 hours. Since pollen is viable for less than 24 hours, this assures that the silks are not pollinated from other pollen sources, that any stray pollen on the tassels of the first plant is dead, and that the only pollen transferred comes from the first plant. The pollen bag over the tassel of the first plant is then shaken vigorously to enhance release of pollen from the tassels, and the shoot bag is removed from the silks of the incipient ear on the second plant. Finally, the pollen bag is removed from the tassel of the first plant and is placed over the silks of the incipient ear of the second plant, shaken again and left in place. Yet another step comprises harvesting the seeds from at least one of the parent corn plants. The harvested seed can be grown to produce a corn plant or hybrid corn plant.

The present invention also provides corn seed and plants produced by a process that comprises crossing a first parent corn plant with a second parent corn plant, wherein at least one of the first or second parent corn plants is a plant of the variety designated I294213. In one embodiment of the invention, corn seed and plants produced by the process are first generation (F.sub.1) hybrid corn seed and plants produced by crossing an inbred in accordance with the invention with another, distinct inbred. The present invention further contemplates seed of an F.sub.1 hybrid corn plant. Therefore, certain exemplary embodiments of the invention provide an F.sub.1 hybrid corn plant and seed thereof.

In still yet another aspect of the invention, the genetic complement of the corn plant variety designated I294213 is provided. The phrase "genetic complement" is used to refer to the aggregate of nucleotide sequences, the expression of which sequences defines the phenotype of, in the present case, a corn plant, or a cell or tissue of that plant. A genetic complement thus represents the genetic make up of an inbred cell, tissue or plant, and a hybrid genetic complement represents the genetic make up of a hybrid cell, tissue or plant. The invention thus provides corn plant cells that have a genetic complement in accordance with the inbred corn plant cells disclosed herein, and plants, seeds and diploid plants containing such cells.

Plant genetic complements may be assessed by genetic marker profiles, and by the expression of phenotypic traits that are characteristic of the expression of the genetic complement. It is understood that variety I294213 could also be identified by many types of genetic markers such as, for example, Simple Sequence Length Polymorphisms (SSLPs) (Williams et al., 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNA Amplification Fingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858, specifically incorporated herein by reference in its entirety), and Single Nucleotide Polymorphisms (SNPs) (Wang et al., 1998).

In still yet another aspect, the present invention provides hybrid genetic complements, as represented by corn plant cells, tissues, plants, and seeds, formed by the combination of a haploid genetic complement of an inbred corn plant of the invention with a haploid genetic complement of a second corn plant, preferably, another, distinct inbred corn plant. In another aspect, the present invention provides a corn plant regenerated from a tissue culture that comprises a hybrid genetic complement of this invention.

In still yet another aspect, the present invention provides a method of producing an inbred corn plant derived from the corn variety I294213, the method comprising the steps of: (a) preparing a progeny plant derived from corn variety I294213, wherein said preparing comprises crossing a plant of the corn variety I294213 with a second corn plant; (b) crossing the progeny plant with itself or a second plant to produce a seed of a progeny plant of a subsequent generation; (c) growing a progeny plant of a subsequent generation from said seed of a progeny plant of a subsequent generation and crossing the progeny plant of a subsequent generation with itself or a second plant; and (d) repeating steps (c) and (d) for an addition 3-10 generations to produce an inbred corn plant derived from the corn variety I294213. In the method, it may be desirable to select particular plants resulting from step (c) for continued crossing according to steps (b) and (c). By selecting plants having one or more desirable traits, an inbred corn plant derived from the corn variety I294213 is obtained which possesses some of the desirable traits of corn variety I294213 as well potentially other selected traits.

DETAILED DESCRIPTION OF THE INVENTION

I. Definitions of Plant Characteristics

Barren Plants: Plants that are barren, i.e., lack an ear with grain, or have an ear with only a few scattered kernels.

Cg: Colletotrichum graminicola rating. Rating times 10 is approximately equal to percent total plant infection.

CLN: Corn Lethal Necrosis (combination of Maize Chlorotic Mottle Virus and Maize Dwarf Mosaic virus) rating: numerical ratings are based on a severity scale where 1=most resistant to 9=susceptible.

Cn: Corynebacterium nebraskense rating. Rating times 10 is approximately equal to percent total plant infection.

Cz: Cercospora zeae-maydis rating. Rating times 10 is approximately equal to percent total plant infection.

Dgg: Diatraea grandiosella girdling rating (values are percent plants girdled and stalk lodged).

Dropped Ears: Ears that have fallen from the plant to the ground.

Dsp: Diabrotica species root ratings (1=least affected to 9=severe pruning).

Ear-Attitude: The attitude or position of the ear at harvest scored as upright, horizontal, or pendant.

Ear-Cob Color: The color of the cob, scored as white, pink, red, or brown.

Ear-Cob Diameter: The average diameter of the cob measured at the midpoint.

Ear-Cob Strength: A measure of mechanical strength of the cobs to breakage, scored as strong or weak.

Ear-Diameter: The average diameter of the ear at its midpoint.

Ear-Dry Husk Color: The color of the husks at harvest scored as buff, red, or purple.

Ear-Fresh Husk Color: The color of the husks 1 to 2 weeks after pollination scored as green, red, or purple.

Ear-Husk Bract: The length of an average husk leaf scored as short, medium, or long.

Ear-Husk Cover: The average distance from the tip of the ear to the tip of the husks. Minimum value no less than zero.

Ear-Husk Opening: An evaluation of husk tightness at harvest scored as tight, intermediate, or open.

Ear-Length: The average length of the ear.

Ear-Number Per Stalk: The average number of ears per plant.

Ear-Shank Internodes: The average number of internodes on the ear shank.

Ear-Shank Length: The average length of the ear shank.

Ear-Shelling Percent: The average of the shelled grain weight divided by the sum of the shelled grain weight and cob weight for a single ear.

Ear-Silk Color: The color of the silk observed 2 to 3 days after silk emergence scored as green-yellow, yellow, pink, red, or purple.

Ear-Taper (Shape): The taper or shape of the ear scored as conical, semi-conical, or cylindrical.

Ear-Weight: The average weight of an ear.

Early Stand: The percent of plants that emerge from the ground as determined in the early spring.

ER: Ear rot rating (values approximate percent ear rotted).

Final Stand Count: The number of plants just prior to harvest.

GDUs: Growing degree units which are calculated by the Barger Method, where the heat units for a 24-h period are calculated as GDUs=[(Maximum daily temperature+Minimum daily temperature)/2]-50. The highest maximum daily temperature used is 86.degree. F. and the lowest minimum temperature used is 50.degree. F.

GDUs to Shed: The number of growing degree units (GDUs) or heat units required for an inbred line or hybrid to have approximately 50% of the plants shedding pollen as measured from time of planting. GDUs to shed is determined by summing the individual GDU daily values from planting date to the date of 50% pollen shed.

GDUs to Silk: The number of growing degree units for an inbred line or hybrid to have approximately 50% of the plants with silk emergence as measured from time of planting. GDUs to silk is determined by summing the individual GDU daily values from planting date to the date of 50% silking.

Hc2: Helminthosporium carbonum race 2 rating. Rating times 10 is approximately equal to percent total plant infection.

Hc3: Helminthosporium carbonum race 3 rating. Rating times 10 is approximately equal to percent total plant infection.

Hm: Helminthosporium maydis race 0 rating. Rating times 10 is approximately equal to percent total plant infection.

Ht1: Helminthosporium turcicum race 1 rating. Rating times 10 is approximately equal to percent total plant infection.

Ht2: Helminthosporium turcicum race 2 rating. Rating times 10 is approximately equal to percent total plant infection.

HtG: Chlorotic-lesion type resistance. +=indicates the presence of Ht chlorotic-lesion type resistance; -=indicates absence of Ht chlorotic-lesion type resistance; and +/-=indicates segregation of Ht chlorotic-lesion type resistance. Rating times 10 is approximately equal to percent total plant infection.

Kernel-Aleurone Color: The color of the aleurone scored as white, pink, tan, brown, bronze, red, purple, pale purple, colorless, or variegated.

Kernel-Cap Color: The color of the kernel cap observed at dry stage, scored as white, lemon-yellow, yellow, or orange.

Kernel-Endosperm Color: The color of the endosperm scored as white, pale yellow, or yellow.

Kernel-Endosperm Type: The type of endosperm scored as normal, waxy, or opaque.

Kernel-Grade: The percent of kernels that are classified as rounds.

Kernel-Length: The average distance from the cap of the kernel to the pedicel.

Kernel-Number Per Row: The average number of kernels in a single row.

Kernel-Pericarp Color: The color of the pericarp scored as colorless, red-white crown, tan, bronze, brown, light red, cherry red, or variegated.

Kernel-Row Direction: The direction of the kernel rows on the ear scored as straight, slightly curved, spiral, or indistinct (scattered).

Kernel-Row Number: The average number of rows of kernels on a single ear.

Kernel-Side Color: The color of the kernel side observed at the dry stage, scored as white, pale yellow, yellow, orange, red, or brown.

Kernel-Thickness: The distance across the narrow side of the kernel.

Kernel-Type: The type of kernel scored as dent, flint, or intermediate.

Kernel-Weight: The average weight of a predetermined number of kernels.

Kernel-Width: The distance across the flat side of the kernel.

Kz: Kabatiella zeae rating. Rating times 10 is approximately equal to percent total plant infection.

Leaf-Angle: Angle of the upper leaves to the stalk scored as upright (0 to 30 degrees), intermediate (30 to 60 degrees), or lax (60 to 90 degrees).

Leaf-Color: The color of the leaves 1 to 2 weeks after pollination scored as light green, medium green, dark green, or very dark green.

Leaf-Length: The average length of the primary ear leaf.

Leaf-Longitudinal Creases: A rating of the number of longitudinal creases on the leaf surface 1 to 2 weeks after pollination. Creases are scored as absent, few, or many.

Leaf-Marginal Waves: A rating of the waviness of the leaf margin 1 to 2 weeks after pollination. Rated as none, few, or many.

Leaf-Number: The average number of leaves of a mature plant. Counting begins with the cotyledonary leaf and ends with the flag leaf.

Leaf-Sheath Anthocyanin: A rating of the level of anthocyanin in the leaf sheath 1 to 2 weeks after pollination, scored as absent, basal-weak, basal-strong, weak or strong.

Leaf-Sheath Pubescence: A rating of the pubescence of the leaf sheath. Ratings are taken 1 to 2 weeks after pollination and scored as light, medium, or heavy.

Leaf-Width: The average width of the primary ear leaf measured at its widest point.

LSS: Late season standability (values times 10 approximate percent plants lodged in disease evaluation plots).

Moisture: The moisture of the grain at harvest.

On1: Ostrinia nubilalis 1st brood rating (1=resistant to 9=susceptible).

On2: Ostrinia nubilalis 2nd brood rating (1=resistant to 9=susceptible).

Relative Maturity: A maturity rating based on regression analysis. The regression analysis is developed by utilizing check hybrids and their previously established day rating versus actual harvest moistures. Harvest moisture on the hybrid in question is determined and that moisture value is inserted into the regression equation to yield a relative maturity.

Root Lodging: Root lodging is the percentage of plants that root lodge. A plant is counted as root lodged if a portion of the plant leans from the vertical axis by approximately 30 degrees or more.

Seedling Color: Color of leaves at the 6 to 8 leaf stage.

Seedling Height: Plant height at the 6 to 8 leaf stage.

Seedling Vigor: A visual rating of the amount of vegetative growth on a 1 to 9 scale, where 1 equals best. The score is taken when the average entry in a trial is at the fifth leaf stage.

Selection Index: The selection index gives a single measure of hybrid's worth based on information from multiple traits. One of the traits that is almost always included is yield. Traits may be weighted according to the level of importance assigned to them.

Sr: Sphacelotheca reiliana rating is actual percent infection.

Stalk-Anthocyanin: A rating of the amount of anthocyanin pigmentation in the stalk. The stalk is rated 1 to 2 weeks after pollination as absent, basal-weak, basal-strong, weak, or strong.

Stalk-Brace Root Color: The color of the brace roots observed 1 to 2 weeks after pollination as green, red, or purple.

Stalk-Diameter: The average diameter of the lowest visible internode of the stalk.

Stalk-Ear Height: The average height of the ear measured from the ground to the point of attachment of the ear shank of the top developed ear to the stalk.

Stalk-Internode Direction: The direction of the stalk internode observed after pollination as straight or zigzag.

Stalk-Internode Length: The average length of the internode above the primary ear.

Stalk Lodging: The percentage of plants that did stalk lodge. Plants are counted as stalk lodged if the plant is broken over or off below the ear.

Stalk-Nodes With Brace Roots: The average number of nodes having brace roots per plant.

Stalk-Plant Height: The average height of the plant as measured from the soil to the tip of the tassel.

Stalk-Tillers: The percent of plants that have tillers. A tiller is defined as a secondary shoot that has developed as a tassel capable of shedding pollen.

Staygreen: Staygreen is a measure of general plant health near the time of black layer formation (physiological maturity). It is usually recorded at the time the ear husks of most entries within a trial have turned a mature color. Scoring is on a 1 to 9 basis where 1 equals best.

STR: Stalk rot rating (values represent severity rating of 1=25% of inoculated internode rotted to 9=entire stalk rotted and collapsed).

SVC: Southeastern Virus Complex (combination of Maize Chlorotic Dwarf Virus and Maize Dwarf Mosaic Virus) rating; numerical ratings are based on a severity scale where 1=most resistant to 9=susceptible (1988 reactions are largely Maize Dwarf Mosaic Virus reactions).

Tassel-Anther Color: The color of the anthers at 50% pollen shed scored as green-yellow, yellow, pink, red, or purple.

Tassel-Attitude: The attitude of the tassel after pollination scored as open or compact.

Tassel-Branch Angle: The angle of an average tassel branch to the main stem of the tassel scored as upright (less than 30 degrees), intermediate (30 to 45 degrees), or lax (greater than 45 degrees).

Tassel-Branch Number: The average number of primary tassel branches.

Tassel-Glume Band: The closed anthocyanin band at the base of the glume scored as present or absent.

Tassel-Glume Color: The color of the glumes at 50% shed scored as green, red, or purple.

Tassel-Length: The length of the tassel measured from the base of the bottom tassel branch to the tassel tip.

Tassel-Peduncle Length: The average length of the tassel peduncle, measured from the base of the flag leaf to the base of the bottom tassel branch.

Tassel-Pollen Shed: A visual rating of pollen shed determined by tapping the tassel and observing the pollen flow of approximately five plants per entry. Rated on a 1 to 9 scale where 9=sterile, 1=most pollen.

Tassel-Spike Length: The length of the spike measured from the base of the top tassel branch to the tassel tip.

Test Weight: Weight of the grain in pounds for a given volume (bushel) adjusted to 15.5% moisture.

Yield: Yield of grain at harvest adjusted to 15.5% moisture.

II. Other Definitions

Allele: Any of one or more alternative forms of a gene locus, all of which alleles relate to one trait or characteristic. In a diploid cell or organism, the two alleles of a given gene occupy corresponding loci on a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybrid progeny back to one of the parents, for example, a first generation hybrid (F.sub.1) with one of the parental genotypes of the F.sub.1 hybrid.

Chromatography: A technique wherein a mixture of dissolved substances are bound to a solid support followed by passing a column of fluid across the solid support and varying the composition of the fluid. The components of the mixture are separated by selective elution.

Converted (Conversion) Plant: Plants which are developed by a plant breeding technique called backcrossing wherein essentially all of the desired morphological and physiological characteristics of an inbred are recovered in addition to one or more new trait conferred by the genetic locus transferred into the inbred via the backcrossing technique. By "new trait," it is understood that the trait may or may not be naturally occurring in maize, but is added or modified with respect to the starting inbred. A genetic locus may comprise one or more genes. In the case of transgenes, one or more transgenes are commonly integrated into a host genome at a given locus. Such transgenes may comprise selectable markers, enhancers, or other components of the transformation vector used.

Crossing: The pollination of a female flower of a corn plant, thereby resulting in the production of seed from the flower.

Cross-pollination: Fertilization by the union of two gametes from different plants.

Diploid: A cell or organism having two sets of chromosomes.

Electrophoresis: A process by which particles suspended in a fluid or a gel matrix are moved under the action of an electrical field, and thereby separated according to their charge and molecular weight. This method of separation is well known to those skilled in the art and is typically applied to separating various forms of enzymes and of DNA fragments produced by restriction endonucleases.

Emasculate: The removal of plant male sex organs or the inactivation of the organs with a chemical agent or a cytoplasmic or nuclear genetic factor conferring male sterility.

Enzymes: Molecules which can act as catalysts in biological reactions.

F.sub.1 Hybrid: The first generation progeny of the cross of two plants.

Genetic Complement: An aggregate of nucleotide sequences, the expression of which sequences defines the phenotype in corn plants, or components of plants including cells or tissue.

Genotype: The genetic constitution of a cell or organism.

Haploid: A cell or organism having one set of the two sets of chromosomes in a diploid.

Isozymes: Detectable variants of an enzyme, the variants catalyzing the same reaction(s) but differing from each other, e.g., in primary structure and/or electrophoretic mobility. The differences between isozymes are under single gene, codominant control. Consequently, electrophoretic separation to produce band patterns can be equated to different alleles at the DNA level. Structural differences that do not alter charge cannot be detected by this method.

Isozyme typing profile: A profile of band patterns of isozymes separated by electrophoresis that can be equated to different alleles at the DNA level.

Linkage: A phenomenon wherein alleles on the same chromosome tend to segregate together more often than expected by chance if their transmission was independent.

Marker: A readily detectable phenotype, preferably inherited in codominant fashion (both alleles at a locus in a diploid heterozygote are readily detectable), with no environmental variance component, i.e., heritability of 1.

Phenotype: The detectable characteristics of a cell or organism, which characteristics are the manifestation of gene expression.

Quantitative Trait Loci (QTL): Genetic loci that contribute, at least in part, certain numerically representable traits that are usually continuously distributed.

Regeneration: The development of a plant from tissue culture.

SSR profile: A profile of simple sequence repeats used as genetic markers and scored by gel electrophoresis following PCR.TM. amplification using flanking oligonucleotide primers.

Self-pollination: The transfer of pollen from the anther to the stigma of the same plant.

Tissue Culture: A composition comprising isolated cells of the same or a different type or a collection of such cells organized into parts of a plant.

Transgene: A genetic sequence which has been introduced into the nuclear or chloroplast genome of a maize plant by a genetic transformation technique.

The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples that follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments that are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

III. Inbred Corn Plant I294213

In accordance with one aspect of the present invention, there is provided a novel inbred corn plant variety designated I294213. Inbred corn plant I294213 can be compared to other inbred corn plants. Examples of such comparisons are provided in Tables 1 and 2.

TABLE-US-00001 TABLE 1 Comparison of Corn Variety I294213 with Corn Variety I112443 I294213 I112443 DIFF P VALUE BARREN % 2.9 3.0 0.1 0.975 EHT INCH 37.1 29.8 7.3 0.166 FINAL 69.5 61.8 7.6 0.000** MST % 23.0 22.6 0.3 0.756 PHT INCH 73.1 70.5 2.6 0.609 RTL % 1.1 0.4 0.7 0.522 SHED GDU 1402.0 1472.2 -70.1 0.000** SILK GDU 1432.8 1492.8 -59.9 0.002* STL % 0.9 2.9 -2.0 0.000** YLD BU/A 118.4 69.4 49.0 0.000** Significance Levels are indicated as: += 10%, *= 5%, **= 1%. Legend Abbreviations: BARREN % = Barren Plants (percent) EHT INCH = Ear Height (inches) FINAL = Final Stand MST % = Moisture (percent) PHT INCH = Plant Height (inches) RTL % = Root Lodging (percent) SHED GDU = GDUs to Shed SILK GDU = GDUs to Silk STL % = Stalk Lodging (percent) YLD BU/A = Yield (bushels/acre)

TABLE-US-00002 TABLE 2 Comparison of Corn Variety I294213 with Corn Variety I881032 I294213 I881032 DIFF P VALUE BARREN % 2.9 2.5 0.4 0.826 EHT INCH 37.1 30.8 6.3 0.227 FINAL 69.5 64.5 5.0 0.000** MST % 23.0 19.7 3.2 0.007* PHT INCH 73.1 81.6 -8.4 0.117 RTL % 1.1 1.5 -0.4 0.785 SHED GDU 1402.0 1436.1 -34.1 0.060+ SILK GDU 1432.8 1474.4 -41.5 0.028+ STL % 0.9 3.7 -2.7 0.000** YLD BU/A 118.4 90.2 28.2 0.000** Significance Levels are indicated as: += 10%, *= 5%, **= 1%. Legend Abbreviations: BARREN % = Barren Plants (percent) EHT INCH = Ear Height (inches) FINAL = Final Stand MST % = Moisture (percent) PHT INCH = Plant Height (inches) RTL % = Root Lodging (percent) SHED GDU = GDUs to Shed SILK GDU = GDUs to Silk STL % = Stalk Lodging (percent) YLD BU/A = Yield (bushels/acre)

A. Origin and Breeding History

Inbred plant I294213 was derived from the initial cross of inbred lines 01DHD10 and 90DJD28. The origin and breeding history of inbred plant I294213 can be summarized as follows:

TABLE-US-00003 Summer 1996 The inbred line 01DHD10 (a proprietary Monsanto Company inbred) was crossed to the inbred line 90DJD28 (a proprietary Monsanto Company inbred) in nursery rows 96: 308-46 and 96: 309-45. Winter 1996 The S0 seed was grown and self-pollinated in nursery row 6W: 2X38-61. Summer 1997 The S1 seed was grown and self-pollinated in nursery rows 97: 3-36 through 97: 3-55. 64 ears were selected. Summer 1998 S2 ears were grown ear-to-row and self-pollinated. 4 ears were selected in nursery row 98: 63-38. Winter 1998 S3 ears were grown ear-to-row and self-pollinated. In nursery row 98W: MX-1297. 3 ears were selected. Summer 1999 S4 ears were grown ear-to-row and self-pollinated. 3 ears from nursery row 99: 79-5 were selected and designated as Corn variety I294213. Winter 1999 S5 ears were grown ear-to-row and self-pollinated. 7 ears from nursery row 9K6WQ17-31 were selected. Summer 2000 S6 ears were grown ear-to-row and self-pollinated. The final 30 ears were selected from nursery rows 2000: 203-44 through 2000: 203-46.

Corn variety I294213 shows uniformity and stability within the limits of environmental influence for the traits described hereinafter in Table 3. I294213 has been self-pollinated and ear-rowed a sufficient number of generations with careful attention paid to uniformity of plant type to ensure homozygosity and phenotypic stability. No variant traits have been observed or are expected in I294213.

Inbred corn plants can be reproduced by planting the seeds of the inbred corn plant I294213, growing the resulting corn plants under self-pollinating or sib-pollinating conditions with adequate isolation using standard techniques well known to an artisan skilled in the agricultural arts. Seeds can be harvested from such a plant using standard, well known procedures.

B. Phenotypic Description

In accordance with another aspect of the present invention, there is provided a corn plant having the physiological and morphological characteristics of corn plant I294213. A description of the physiological and morphological characteristics of corn plant I294213 is presented in Table 3.

TABLE-US-00004 TABLE 3 Morphological Traits for Corn Variety I294213 and Comparative Corn Varieties VALUE CHARACTERISTIC I294213 I112443 I881032 1. STALK Diameter (width) cm. 2.0 2.2 2.3 Anthocyanin Basel-Weak Absent Absent Brace Root Color Dark Dark Moderate Nodes With Brace 2.1 2.3 1.6 Roots Internode Direction Straight Straight Straight Internode Length cm. 12.3 13.9 14.1 2. LEAF Color Dark Green Green Dark Green Length cm. 73.2 61.2 76.5 Width cm. 8.9 7.1 7.6 Sheath Anthocyanin Weak Weak Weak Sheath Pubescence Moderate Moderate Heavy Marginal Waves Few Few Few Longitudinal Creases Moderate Moderate Few 3. TASSEL Length cm. 37.9 33.5 41.8 Spike Length cm. 22.4 16.7 25.1 Peduncle Length cm. 7.9 9.8 8.5 Branch Number 4.7 6.1 5.5 Anther Color Pink Pink Pink Glume Color Green Green Green Glume Band Absent Absent Absent 4. EAR Silk Color Tan Green-Yellow Pink Number Per Stalk 1.0 1.0 1.2 Position (attitude) -- Upright Pendent Length cm. 12.0 14.5 16.4 Shape Semi- Semi-Conical Semi- Conical Conical Diameter cm. 4.1 4.1 4.0 Shank Length cm. 11.4 8.0 6.7 Husk Bract Short Short Short Husk Cover cm. 2.0 5.5 5.4 Husk Opening Tight Intermediate Intermediate Husk Color Fresh Green Green Green Husk Color Dry Buff Buff Buff Cob Diameter cm. 2.4 2.5 2.3 Cob Color Red Red Red Shelling Percent 87.5 83.9 85.9 5. KERNEL Row Number 16.2 17.4 14.5 Number Per Row 24.9 29.5 34.8 Row Direction Straight Slightly Slightly Curved Curved Type Dent Dent Dent Cap Color Deep-Yellow Yellow Yellow Side Color Yellow- Deep-Yellow Orange Orange Length (depth) mm. 11.4 11.1 10.9 Width mm. 7.1 6.7 7.4 Thickness 3.9 4.0 3.3 Endosperm Type Normal Normal Normal Endosperm Color Yellow Yellow Yellow *These are typical values. Values may vary due to environment. Other values that are substantially equivalent are also within the scope of the invention.

C. Deposit Information

A representative deposit of 2500 seeds of the inbred corn variety designated I294213 has been made with the American Type Culture Collection (ATCC), 10801 University Blvd., Manassas, Va on Sep. 13, 2006. Those deposited seeds have been assigned ATCC Accession No. PTA-7859. The deposit was made in accordance with the terms and provisions of the Budapest Treaty relating to deposit of microorganisms and was made for a term of at least thirty (30) years and at least five (05) years after the most recent request for the furnishing of a sample of the deposit is received by the depository, or for the effective term of the patent, whichever is longer, and will be replaced if it becomes non-viable during that period.

IV. Conversions of Variety I294213

When the term inbred corn plant is used in the context of the present invention, this also includes any conversions of that inbred to express one or more new traits. The term converted plant as used herein refers to those corn plants which are developed by a plant breeding technique called backcrossing, wherein essentially all of the desired morphological and physiological characteristics of an inbred are recovered in addition to the genetic locus transferred into the inbred via the backcrossing technique. Backcrossing methods can be used with the present invention to improve or introduce a trait into the inbred. The term backcrossing as used herein refers to the repeated crossing of a hybrid progeny back to one of the parental corn plants for that inbred. The parental corn plant which contributes the locus or loci for the desired trait is termed the nonrecurrent or donor parent. This terminology refers to the fact that the nonrecurrent parent is used one time in the backcross protocol and therefore does not recur. The parental corn plant to which the locus or loci from the nonrecurrent parent are transferred is known as the recurrent parent as it is used for several rounds in the backcrossing protocol (Poehlman et al., 1995; Fehr, 1987; Sprague and Dudley, 1988). In a typical backcross protocol, the original inbred of interest (recurrent parent) is crossed to a second inbred (nonrecurrent parent) that carries the genetic locus of interest to be transferred. The resulting progeny from this cross are then crossed again to the recurrent parent and the process is repeated until a corn plant is obtained wherein essentially all of the desired morphological and physiological characteristics of the recurrent parent are recovered in the converted plant, in addition to the transferred locus from the nonrecurrent parent. The backcross process may be accelerated by the use of genetic markers, such as SSR, RFLP, SNP or AFLP markers to identify plants with the greatest genetic complement from the recurrent parent.

The selection of a suitable recurrent parent is an important step for a successful backcrossing procedure. The goal of a backcross protocol is to add or substitute one or more new traits in the original inbred. To accomplish this, a genetic locus of the recurrent inbred is modified or substituted with the desired locus from the nonrecurrent parent, while retaining essentially all of the rest of the desired genetic, and therefore the desired physiological and morphological constitution of the original inbred. The choice of the particular nonrecurrent parent will depend on the purpose of the backcross; one of the major purposes is to add some commercially desirable, agronomically important trait to the plant. The exact backcrossing protocol will depend on the characteristic or trait being altered to determine an appropriate testing protocol. Although backcrossing methods are simplified when the characteristic being transferred is a dominant allele, a recessive allele may also be transferred. In this instance it may be necessary to introduce a test of the progeny to determine if the desired characteristic has been successfully transferred.

Many traits have been identified that are not regularly selected for in the development of a new inbred but that can be improved by backcrossing techniques. A genetic locus conferring the traits may or may not be transgenic. Examples of such traits known to those of skill in the art include, but are not limited to, male sterility, waxy starch, herbicide resistance, resistance for bacterial, fungal, or viral disease, insect resistance, male fertility, enhanced nutritional quality, industrial usage, yield stability, and yield enhancement. These genes are generally inherited through the nucleus, but may be inherited through the cytoplasm. Some known exceptions to this are genes for male sterility, some of which are inherited cytoplasmically, but still act as a single locus trait. A number of exemplary genetic loci conferring new traits are described in, for example, PCT Application WO 95/06128, the disclosure of which is specifically incorporated herein by reference.

Examples of genes conferring male sterility include those disclosed in U.S. Pat. Nos. 3,861,709, 3,710,511, 4,654,465, 5,625,132, and 4,727,219, each of the disclosures of which are specifically incorporated herein by reference in their entirety. A particularly useful type of male sterility gene is one which can be induced by exposure to a chemical agent, for example, a herbicide (U.S. patent Ser. No. 08/927,368, filed Sep. 11, 1997, the disclosure of which is specifically incorporated herein by reference in its entirety). Both inducible and non-inducible male sterility genes can increase the efficiency with which hybrids are made, in that they eliminate the need to physically emasculate the corn plant used as a female in a given cross.

Where one desires to employ male-sterility systems with a corn plant in accordance with the invention, it may be beneficial to also utilize one or more male-fertility restorer genes. For example, where cytoplasmic male sterility (CMS) is used, hybrid seed production requires three inbred lines: (1) a cytoplasmically male-sterile line having a CMS cytoplasm; (2) a fertile inbred with normal cytoplasm, which is isogenic with the CMS line for nuclear genes ("maintainer line"); and (3) a distinct, fertile inbred with normal cytoplasm, carrying a fertility restoring gene ("restorer" line). The CMS line is propagated by pollination with the maintainer line, with all of the progeny being male sterile, as the CMS cytoplasm is derived from the female parent. These male sterile plants can then be efficiently employed as the female parent in hybrid crosses with the restorer line, without the need for physical emasculation of the male reproductive parts of the female parent.

The presence of a male-fertility restorer gene results in the production of fully fertile F.sub.1 hybrid progeny. If no restorer gene is present in the male parent, male-sterile hybrids are obtained. Such hybrids are useful where the vegetative tissue of the corn plant