Abstract:
An inbred corn line, designated NP 2034, is disclosed. The invention relates to the seeds of inbred corn line NP 2034, to the plants of inbred corn line NP 2034 and to methods for producing a corn plant produced by crossing inbred line NP 2034 with itself or with another corn plant. The invention further relates to hybrid corn seeds and plants produced by crossing inbred line NP 2034 with another corn line.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a new and distinctive corn inbred line designated NP 2034 and to hybrids made by using NP 2034 as a parent. 
     Corn (Zea mays) is a valuable and important field crop. Thus, plant breeders are continually developing new and superior corn inbred lines for production of high yielding, agronomically sound hybrids. The goal of the plant breeder is to combine in a single variety or hybrid an improved combination of desirable traits from the parent, inbred germplasm. These traits may include maximization of yield, resistance to disease and insects, tolerance to drought, heat and other environmental stresses. These traits are governed by a complex genetic system that makes selection and breeding of an inbred line challenging. 
     Corn hybrid development requires the development of homozygous inbred lines, the crossing of these lines, and the subsequent evaluation of those crosses. Pedigree, backcross, and recurrent selection breeding methods are used to develop inbred lines from breeding populations. Breeding programs combine the genetic backgrounds from two or more inbred lines or various other genetic sources into breeding pools from which new inbred lines are developed by self pollination and selection of desired phenotypes. The new inbred lines are crossed with other inbred lines, and hybrids from these crosses are evaluated to determine which have commercial potential. 
     Once the inbred parents that give a superior hybrid are identified, the hybrid seed can be reproduced indefinitely as long as inbred parent homogeneity is maintained. Corn hybrids may be either single cross hybrids, produced when two inbred lines are crossed to produce the first generation (F1) progeny; double cross hybrids, produced from four inbred lines crossed in pairs (A×B and C×D) and then the two F1 hybrids are crossed again (A×B)×(C×D); or three-way cross hybrids produced from crossing a single cross (A×B) to a third inbred line C. Numerous references are available on the topic of corn breeding and hybrid seed corn production. Those skilled in the art of corn breeding and production are well aware of techniques and methods for the development of inbred corn lines and corn hybrids. However, while many of the techniques and methods are known, breeder care and expertise must be used in the selection of breeding material for resulting yield increase and superior agronomic traits. Reference is made particularly to Corn and Corn Improvement, Third Edition, ed. G. F. Sprague and J. W. Dudley, American Society of Agronomy Monograph No. 18, particularly chapters 8 and 9, the substantive content of which is hereby incorporated by reference. 
     SUMMARY OF THE INVENTION 
     According to the invention, there is provided a novel inbred corn line, designated NP 2034. This invention thus relates to the seeds of inbred corn line NP 2034, to the plants of inbred corn line NP 2034 and to methods of producing a corn plant comprising the crossing of inbred corn line NP 2034 with itself or another corn line. 
     This invention further relates to hybrid corn seed produced by crossing the inbred line NP 2034 with another corn inbred line. More specifically the invention extends to hybrid corn seed produced by planting in pollinating proximity seeds of inbred corn line NP 2034 and a second inbred line having a genotype different from NP 2034; cultivating corn plants resulting from said planting until time of flowering; emasculating the flowers of plants of one of the inbred lines; allowing cross pollination to occur between the inbred lines; and harvesting seeds produced on the plants of the inbred line. The hybrid plants grown from the seed produced as stated above. 
     DEFINITIONS 
     In the description and examples that follow a number of terms are used; therefore, to provide a clear and consistent understanding of the specification and claims the following definitions are provided. 
     RK=Round Kernels: the percentage of kernels that do not pass through a 13/64 slotted screen. 
     HE=Husk Extension: the length (cm) of the husk past the ear tip at maturity. 
     PRM=Predicted Relative Maturity. This trait is based on the harvest moisture of the grain. The relative maturity rating is based on a known set of checks, and is referred to as the Minnesota Relative Rating System. 
     MST=Harvest Moisture. The moisture is the actual percentage moisture of the grain at harvest. 
     STK (BR)=The percentage of plants broken below the ear at harvest. 
     YLD=Yield; bushels per acre. The actual yield of the grain at harvest (bu/a) adjusted to approximately 15.5% moisture. 
     RT=Number of plants lodged (leaning from vertical but not broken). 
     Pit. Ht.=Plant Height; The length of the plant to tassel tip (cm). 
     HU=Heat Units; ##EQU1## 
     HUS=Heat units from emergence to 50% of plants in silk. 
     HU to pollen=Heat units from emergence to 50% of plants in pollen. 
     HU to pollen shed=Heat units from 10% to 90% pollen shed. 
     Ear Ht.=Ear Height. The measurement from the ground to the top developed ear node attachment measured in cm. 
     INTL=Late Season Intactness - the degree to which portion of the plant above the ear remains intact and erect at harvest. The rating is based on a scale 1 to 9 wherein 1 is most intact. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Inbred corn line NP 2034 is a yellow dent inbred line with superior characteristics and is best suited as a male in crosses for production of first generation (F1) corn hybrids. NP 2034 is best adapted to the North central Cornbelt Area of the United States. NP 2034 can be used to produce hybrids from approximately 115-125 PRM days based on the Minnesota Relative Maturity Rating System for harvest of grain. Inbred line NP 2034 has demonstrated good combining ability with families derived from Iowa Stiff Stalk, for example, B73 and related lines. 
     Inbred corn line NP 2034 was derived from the crossing LH123, Holdens Foundation Seed to Northrup King Co. Proprietary line NP J8606 followed by a backcross to NP J8606. Northrup King Co. J8606 has PVP Cert. No. 8900226. Self-pollination and standard pedigree ear-to-row breeding were practiced within the above backcross population for seven generations in the development of NP 2034. During the development of the line, crosses of segregating families were made to inbred testers to evaluate combining ability. Inbred line NP 2034 can be reproduced by planting seeds of the line, growing the resulting corn plants under self-pollination or sib-pollination conditions with adequate isolation and then harvesting the resulting seed. No variant traits have been observed or are expected in NP 2034. 
     The inbred line has been evaluated at numerous research stations across the Northern United States Corn Belt and Canada. Inbred line NP 2034 has shown uniformity and stability for all discernible characteristics as described in the following variety description. The description is based on data collected primarily at St. Joseph, Ill. and Phillips, Nebr. on a maximum of 4 replications in 1995. In interpreting the color designations herein, reference is made to the Munsell Glossy Book of Color, a standard color reference to describe all color choices. 
     
                       TABLE 1______________________________________VARIETY DESCRIPTION INFORMATION FORINBRED LINE NP 2034 and Mo17                         Mo17              NP2034     DentType:              Dent       NorthernRegion Best Adapted:              North central                         and Central______________________________________A.  Maturity:    HU to Silk (HUS):  1447 (70 days)                             1615 (76 days)    HU to pollen:      1435 (69 days)                             1474 (71 days)    HU to pollen shed: 75.8 (3 days)                             168 (6 days)    Plant Characteristics:    Plant height (to tassel tip) (cm):                  199.5      203    Length of top ear internode (cm):                  16.5       14    Ear height (to base of top ear                  72.5       77.5    internode) (cm):    Number of tillers: 0.25       0    Number of ears per stalk:                  1.4        1    Cytoplasm type:    Normal     Normal    Anthocyanin of brace roots:                  Moderate   FaintC.  Leaf:    Color of second leaf above the                  Green-yellow                             Green-yellow    ear (at anthesis)  (5GY 4/6)  (5G 4/5)    Leaf angle (from 2nd leaf above                  10° 25°    ear at anthesis to stalk above leaf)    Number of leaves-above top ear                  5          5.2    (mature plants):    Marginal waves:    2.5        3.8    (Scale: 1 = none to 9 = many):    Width (widest point of ear node                  8          9.4    leaf) (cm):    Sheath Pubescence: 3.5        2.5    (Scale 0 = none to 9 = many):    Longitudinal creases:                  2.25       1    (Scale: 1 = none to 9 = heavy):    Length (ear node leaf) (cm):                  75.6       69.2D.  Tassel:    Number of primary  5.15       5.4    lateral branches:    Branch angle of secondary primary                  15° 32.5°    lateral branch at anthesis:    Anther color:      Green-yellow                             Green-yellow                  (2.5GY 8/8)                             (5Y 8/6)    Glume color:       Red        Green-yellow                  (5R4/6)    (5GY6/6)    Bar glumes:        absent     absent    Tassel length (from top leaf                  43.4       46.2    collar to tassel tip):E.  Ear (Husked ear data except    where stated otherwise):    Length (cm):       14.2       18    Weight (gm):       96.6       107    Midpoint diameter (mm):                  38.65      35.6    Kernel rows:       11.8 Distinct                             10.6 Distinct    Row alignment      Straight   Straight    Silk color (3 days Red        Green-Yellow    after emergence):  (SR 5/6)   (2.5GY 8/8)    Husk extension:    Medium     Medium - Long    Taper of ear:      Average    Average    Husk color (fresh)    25 days after 50% silking:                  Green-yellow                             Green-yellow    Husk color (dry)   (5GY 7/8)  (5 GY 7/8)    65 days after 50% silking:                  Yellow     Yellow                  (5Y 8/8)   (5Y 8/6)    Shank length (cm): 5.25       5.0F.  Kernel (Dried):    Size (from ear mid-point):    Length (mm):       7.5        10.25    Width (mm):        8.75       8.0    Thickness (mm):    3.5        4.75    Shape grade (% rounds):                  33.2       54.0    Aleurone color:    Homozygous Homozygous                  Yellow     Yellow    Endosperm color:   Yellow-orange                             Yellow-orange                  (7.5YR 7/10)                             (7.5YR 6/10)    Endosperm type:    Normal starch                             Normal starch    Gm weight/100 seeds (unsized):                  27.4       23.25G.  Cob:    Diameter at mid-point (mm):                  23.2       20.7    Color:             Red        RedH.  Agronomic Traits:    Stay Green, 65 days after anthesis                  4.5        8    Scale 1 = worst    to 9 = excellent):    Root lodging, 65 days after                  0    anthesis (%):      0I   Disease Resistance:    Northern leaf blight:                  5          3    Exserohilum turcicum    Grey leaf spot:    5          3    Cercospora zea-maydis    Southern leaf blight:                  5          3    Bipolaris maydis:J.  Insect Resistance:    European Corn Borer    (Ostrinia nubilialis)    1st generation:    5          3    2nd generation:    5          5______________________________________ The above disease and insect resistance description is based on a scale o 1-9; wherein 1-3 is considered susceptible, 4-5 intermediate, 6-7 resistant and 8-9 highly resistant. 
    
     With respect to publicly available inbred lines, NP 2034 most closely resembles Mo17. However, these lines differ in a number of characteristics. The lines differ in plant height, ear height, ear length and number of kernel rows. While NP 2034 is shorter than Mo17 and has lower ear height, it has more kernel rows compared to Mo17. Other characteristics between NP 2034 and Mo17 are summarized in Table 1. 
     With respect to proprietary Northrup King inbred lines, NP 2034 most closely resembles its parent J8606 and may be distinguished from its parent by numerous characteristic including some of the characteristics listed in Table 2 below. NP 2034 may also be distinguished from NP 899, another closely related proprietary inbred line. 
     
                       TABLE 2______________________________________1994 Variety Comparison DataLine   Plt ht (cm)           Ear Ht.  Silk (HU)                           Pollen (HU)                                   INTL______________________________________NP2034 227      83       1452   1421    5.0NP899  240      89       1490   1460    6.0J8606  234      81       1507   1477    3.8#reps  10       10       14     14      10LSD (0.5)  18       12       43     41      3.0______________________________________ The data are taken from Webster City, IA; Napoleon, OH; Phillips, NE; Washington, IA; St. Joseph, IL; Henderson, KY; and Greenville, NC 
    
     In addition to phenotypic observations, the genotype of a plant can also be examined. There are many techniques available for the analysis, comparison and characterization of plant genotype and these include isozyme electrophoresis, restriction fragment length polymorphism (RFLPs), randomly amplified polymorphic DNAs (RAPDs) sequence characterized amplified regions (SCARs) and amplified fragment length polymorphisms (AFLPs). While many of the techniques are used RFLPs have the advantage of revealing an exceptionally high degree of allelic variation in corn. Moreover there are a tremendous number of markers available to use. Reference is made to Mumm and Dudley, A Classification of 148 U.S. Maize Inbreds: I Cluster Analysis based on RFLP&#39;s, Crop Sci., 34:842-851 (1994) and Lee, M &#34;Inbred Lines of Maize and Their Molecular Markers&#34; The Maize Handbook (Springer-Verlag, New York, Inc. 1994 which is hereby incorporated by reference. 
     Both inbred lines NP 2034 and Mol7 were subject to a various RFLP probes and the results indicate that the two inbreds have 47 out of 96 loci with different alleles. Additionally, RFLP relationship data indicate that NP 2034 is distinguished from other closely related inbred lines, for example NP 2034 differs from NP 899 by 18 out of 79 loci. 
     This invention is also directed to methods for producing a corn plant by crossing a first parent corn plant with a second parent corn plant, wherein the first or second corn plant is a corn plant of the inbred line NP 2034. However, both first and second parent corn plant can come from the inbred corn line NP 2034. Therefore any methods using NP 2034 are part of this invention including self-pollination, backcross-pollination, hybrid breeding and crosses to populations. It may be desirable to use a male-sterile (either cytoplasmic or nuclear) female parent to prevent self-pollination. If the female is not male-sterile, then either physical or chemical steps may be taken to ensure that self-pollination does not occur. Any plants produced using inbred corn line NP 2034 as a parent are within the scope of this invention including any plant produced by the use of cells, protoplasts or tissue from NP 2034. 
     Specifically NP 2034 produces hybrids that are competitive yielding. In general, hybrids have good early season vigor, high test weight grain and good stalk quality. 
     The techniques used to obtain the corn hybrid seeds and plants of this invention are conventional in the seed industry and are well known to those skilled in the art. The two parent lines are planted in pollinating proximity to each other in alternating sets of rows; however, any convenient planting pattern that allows for the free transfer of pollen is acceptable. The plants of both inbred lines are allowed to grow until the time of flowering. At flowering, tassels are removed from all plants of the female parent by hand, machine or other means. Natural cross-pollination is allowed to occur. Ears from the female plants are harvested to obtain novel F1 hybrid corn seeds of the present invention. F1 hybrid corn plants of the invention are obtained by planting seeds harvested from the female plant. 
     An example of a competitive yielding hybrid of this invention is that produced by the cross of PVP Certificate No. 8800032×NP 2034. The hybrid produced is a 120 Minnesota Relative Maturity single cross hybrid. This hybrid most closely resembles the commercially available Northrup King Co. hybrid N7992. The hybrid produced by the cross PVP Cert. No 8800032×NP 2034 has significantly yielded more than N7992 and is significantly better for Southern Corn Leaf Blight resistance. Table 3 below illustrates various characteristics of PVP Cert. No. 880032×NP 2034 compared to other similar hybrids. 
     
                                           TABLE 3__________________________________________________________________________Combined Location and Year Performance Data(1994, 1995; 48 environments; 115-125 RM Markets)   YLD      MST         STK (BR)              RT DE    Plt Ht                          Ear Ht.Hybrid  (bu/a)%-%-%-      #  HUS         cm   cm SCLB__________________________________________________________________________PVP Cert.   154      18.8         8    4  1  1349                       247                          112 2.6No. 8800032 xNP 2034N7590   149      17.3         8    4  0  1343                       243                          98  3.0N7992   145      18.2         7    4  0  1408                       261                          118 3.9N7333   143      17.9         8    2  0  1373                       236                          100 4.3Pioneer 3394   143      16.5         5    2  0  1387                       235                          108 4.2Pioneer 3245   155      17.8         7    3  1  1433                       247                          99  3.3Trials with data:   48 48 28   14 6  4  9  9   1LSD     6  0.4         4    3  0  19 11 7   1.2__________________________________________________________________________ SCLB = Southern Leaf Blight, resistance descrption is based on a scale of 1-9; wherein a rating of 1 = best resistance, 9 = most susceptible. 
    
     As used herein the term plant includes plant cells, plant protoplasts, plant cell tissue cultures including that from which corn plants fertile or otherwise can be regenerated, plant calli and plant cell clumps, and differentiated forms of plants such as, but not limited to embryos, pollen, stamen, anthers, flowers, kernels, ears, cobs, leaves, stalks, roots, shoots, plantlets, silks and kernels. In this context, the invention also includes a corn plant regenerated from any NP 2034 corn cell, protoplast and tissue mentioned above and having the same genotype as NP 2034. 
     Methods of cell and tissue culture and regeneration are well known in the art and described for example in &#34;Plant Tissue Culture Manual: Fundamentals and Application&#34;, Ed. K. Lindsey, Kluwer (1991) and in Green and Rhodes, &#34;Plant Regeneration in Tissue Culture of Maize&#34;, Maize for Biological Research (Plant Molecular Biology Association, Charlottesville, Va., 1982, pp. 367-372), which are hereby incorporated by reference. 
     As is well known corn can be put to a wide variety of uses not only as livestock feed but also for human consumption of corn kernels and as a raw material in industry. Both grain and non-grain portions of the plant are used as a livestock feed for swine, cattle and poultry. In the food industry corn is used in wet and dry milling. In wet milling there is the separation of the germ, hull gluten and starch. Germ is used to produce corn oil and germ cake for feed. Corn starch may be packaged for human consumption or used in food products such as sauces, gravies, puddings, sweeteners, syrups, and baking powder. Other nonedible uses include textiles, paper, adhesives, cosmetics, explosives, corn binders, laundry purposes and agricultural formulations. Dry milling is used to produce breakfast foods, grits, cornmeal and corn flour. Other uses of corn include fuel, in the form of fuel alcohol or ethanol; seed; alcoholic beverages and construction. 
     DEPOSIT INFORMATION 
     Deposits of at least 2500 seeds of inbred NP 2034, has been made unrestrictedly available to the public via the American Type Culture Collection (ATCC), Rockville, Md. 20852 USA. The deposit corresponds to ATCC Deposit No. 209539, and was made on Dec. 10, 1997. The seeds are from stock maintained by Northrup King since prior to filing this application or any parents thereof. The deposit of inbred corn line NP 2034 will be maintained in the ATCC depository, which is a public depositary, for a period of 30 years, or 5 years after the most recent request, or for the enforceable life of the patent, whichever, is longer, and will be replaced if it ever becomes nonviable during that period. Additionally, with respect to Plant Variety Protection Certificates received and applied for, Applicant does not waive any infringement of its rights granted under this patent or under the Plant Variety Protection Act (7 U.S.C. 2312 et seq.).