Abstract:
Broadly this invention provides inbred corn line ZS1202. The methods for producing a corn plant by crossing the inbred line ZS1202 are encompassed by the invention. Additionally, the invention relates to the various parts of inbred ZS1202 including culturable cells. This invention relates to hybrid corn seeds and plants produced by crossing the inbred line ZS1202 with at least one other corn line.

Description:
FIELD OF THE INVENTION 
     This invention is in the field of corn breeding, specifically relating to an inbred corn line designated ZS1202. 
     BACKGROUND OF THE INVENTION 
     The original maize plant was indigenous to the Western Hemisphere. The plants were weedlike and only through the efforts of early breeders was a cultivated crop species developed. The physical traits of maize are such that self pollination or cross pollination can occur. Each plant has a separate male and female flower, the tassel and ear, respectively. Natural pollination occurs when wind transfers pollen from tassel to the silks on the corn ears. This type of pollination contributed to the wide variation of maize varieties present in the Western Hemisphere. 
     The development of a planned breeding program for maize only occurred in the last century. Originally, maize was an open pollinated variety having heterogeneous genotypes. The maize farmer selected uniform ears from the yield of these genotypes and reserved them for planting the next season. The result was a field of maize plants that were segregating for a variety of traits. This type of maize selection lead to at most incremental increases in seed yield. 
     Large increases in seed yield were the result of the development of hybrid corn varieties in planned breeding programs. Hybrids were developed by selecting corn lines and selfing these lines for several generations to develop homozygous pure inbred lines and crossing selected inbred lines with unrelated inbred lines to produce hybrid progeny (F1). Inbred lines can be difficult to produce since the inbreeding process in corn decreases the vigor. However, when two inbred lines are crossed, the hybrid plant evidences greatly increased vigor compared to open pollinated segregating maize plants. An important factor of the homozygosity and the homogeneity of the inbred lines is that the hybrid from any cross will always be the same, and can be reproduced. 
     The ultimate objective of the commercial maize seed companies is to produce high yielding, agronomically sound plants which perform well in certain regions or areas of the Corn Belt. To produce these types of hybrids, the companies must develop inbreds which carry needed traits into the hybrid combination. Hybrids are not uniformly adapted for the Corn Belt, but are specifically adapted for regions of the Corn Belt. Northern regions of the Corn Belt require shorter season hybrids than do southern regions of the Corn Belt. Hybrids that grow well in Colorado and Nebraska soils may not flourish in rich Illinois soil. Thus, a variety of major agronomic traits are important in hybrid combination for the various Corn Belt regions, and have an impact on hybrid performance. 
     Inbred line development and hybrid testing have been emphasized in the past half century in commercial maize production as a means to increase hybrid performance. Inbred development is usually done by pedigree selection. Pedigree selection can be selection in an F 2  population produced from a planned cross of two genotypes (often elite inbred lines), or selection of progeny of synthetic varieties, open pollinated, composite, or backcross populations. This type of selection is effective for highly inheritable traits, but other traits, for example, yield requires replicated test crosses at a variety of stages for accurate selection. 
     Maize breeders select for a variety of traits in inbreds that impact hybrid performance along with selecting for acceptable parental traits. Such traits include yield potential in hybrid combination; dry down; maturity; grain moisture at harvest; greensnap; resistance to root lodging; resistance to stalk lodging; grain quality; disease and insect resistance; ear and plant height; performance in different soil types such as: low level of organic matter, clay, sand, black, high pH, low pH; performance in: wet environments, drought environments, and no tillage conditions. These traits appear to be governed by a complex genetic system that makes selection and breeding of an inbred line extremely difficult. Even if an inbred in hybrid combination has excellent yield (a desired characteristic), it may not be useful because it fails to have acceptable parental traits such as seed yield, seed size, pollen production, good silks, plant height, etc. 
     To illustrate the difficulty of breeding and developing inbred lines, the following example is given. Two inbreds compared for similarity of 29 traits differed significantly for 18 traits between the two lines. If 18 simply inherited single gene traits were polymorphic with gene frequencies of 0.5 in the parental lines, and assuming independent segregation (as would essentially be the case if each trait resided on a different chromosome arm), then the specific combination of these traits as embodied in an inbred would only be expected to become fixed at a rate of one in 262,144 possible homozygous genetic combinations. Selection of the specific inbred combination is also influenced by the specific selection environment on many of these 18 traits which makes the probability of obtaining this one inbred even more remote. Thus, the general procedure of producing a non segregating F 1  generation and self pollinating to produce a F 2  generation that segregates for traits does not easily lead to a useful inbred. Great care and breeder expertise must be used in selection of breeding material to continue to increase yield and agronomics of inbreds and resultant commercial hybrids. 
     SUMMARY OF THE INVENTION 
     The present invention relates to an inbred corn line ZS1202. Specifically, this invention relates to plants and seeds of this line. Additionally, this relates to a method of producing hybrid seed corn from this inbred. More particularly, this invention relates to the unique combination of traits that combine in corn line ZS1202. 
     Generally then, broadly the present invention includes an inbred corn seed designated ZS1202. This seed produces a corn plant. 
     The invention also includes the tissue culture of regenerable cells of ZS1202 wherein the tissue regenerates plants having the genotype of ZS1202. The tissue culture is selected from the group consisting of leaves, pollen, embryos, roots, root tips, anthers, silk, flowers, kernels, ears, cobs, husks and stalks, and cells and protoplasts thereof. The corn plant regenerated from ZS1202 having ZS1202&#39;s genotype. 
     The invention extends to hybrid seed produced by planting, in pollinating proximity, seeds of corn inbred lines ZS1202 and another inbred line; cultivating corn plants resulting from said planting; preventing pollen production by the plants of one of the inbred lines; allowing natural cross pollinating to occur between said inbred lines; and harvesting seeds produced on plants of the inbred. The hybrid seed produced by hybrid combination of plants of inbred corn seed designated ZS1202 and plants of another inbred line. Hybrid plants grown from this hybrid seed. 
     The invention further includes a method of hybrid F1 production. A first generation (F1) hybrid corn plant produced by the process of planting, in pollinating proximity, seeds of corn inbred lines ZS1202 and another inbred line; cultivating corn plants resulting from said planting; preventing pollen production by the plants of one of the inbred lines; allowing natural cross pollinating to occur between said inbred lines; harvesting seeds produced on plants of the inbred; and growing a harvested seed. 
     A tissue culture of the regenerable cells of hybrid plants produced with use of ZS1202 genetic material. A tissue culture of the regenerable cells of the corn plant produced by the method described above. 
     DEFINITIONS 
     In the description and examples which follow, a number of terms are used. In order to provide a clear and consistent understanding of the specifications and claims, including the scope to be given such terms, the following definitions are provided. 
     BL MOIST 
     The moisture percentage of the grain at black layer, ie, when 50% of the plants per plot have reached physiological maturity. 
     COLD GERM 
     Cold Germ is a measurement of seed germination under cold soil conditions. Data is reported as percent of seed germinating. 
     ECB 
     European corn borer a maize eating insect. ECBI is the first brood generation of European corn borers. ECBII is the second generation of European corn borers. 
     EMERGE 
     The number of emerged plants per plot (planted at the same seedling rate) collected when plants have two fully developed leaves. 
     GI 
     This is a selection index which provides a single quantitative measure of the worth of a hybrid based on four traits. Yield is the primary trait contributing to index values. The GI value is calculated by combining stalk lodging, root lodging, yield and dropped ears according to the attached mathematical formula: 
     
         GI=100+0.5 (YLD)-0.9(%STALK LODGE)-0.9(%ROOT LODGE)-2.7(%DROPPED EAR) 
    
     GLS 
     Grey Leaf Spot (Cercospora Zeae) disease rating. This is rated on a 1-9 scale with a &#34;1&#34; being very susceptible, and a &#34;9&#34; being very resistant.* 
    
     GW 
     Goss&#39; Wilt (Corynebacterium nebraskense). This is rated on a 1-9 scale with a &#34;1&#34; being very susceptible, and a &#34;9&#34; being very resistant.* 
    
     HEATP10 
     The number of Growing Degree Units (GDU&#39;s) or heat units required for an inbred line or hybrid to have approximately 10 percent of the plants shedding pollen. This trait is measured from the time of planting. Growing Degree Units are calculated by the Barger Method where the GDU&#39;s for a 24 hour period are: ##EQU1## The highest maximum temperature used is 86° F. and the lowest minimum temperature used is 50° F. For each inbred or hybrid it takes a certain number of GDU&#39;s to reach various stages of plant development. 
     HEATBL 
     The number of GDU&#39;s after planting when approximately 50 percent of the inbred or hybrid plants in a plot have grain which has reached physiological maturity (black layer). 
     HEATPEEK 
     The number of GDU&#39;s after planting of an inbred when approximately 50 percent of the plants show visible tassel extension. 
     HEATP50 
     The number of GDU&#39;s required for an inbred or hybrid to have approximately 50 percent of the plants shedding pollen. Growing Degree Units are calculated by the Barger Method as shown in the HEATP10 definition. 
     HEATP90 
     The number of GDU&#39;s accumulated from planting when the last 100 percent of plants in an inbred or hybrid are still shedding enough viable pollen for pollination to occur. Growing Degree Units are calculated by the Barger Method as shown in the HEATP10 definition. 
     HEATS10 
     The number of GDU&#39;s required for an inbred or hybrid to have approximately 10 percent of the plants with silk emergence of at least 0.5 inches. Growing Degree Units are calculated by the Barger Method as shown in the HEATP10 definition. 
     HEATS50 
     The number of GDU&#39;s required for an inbred or hybrid to have approximately 50 percent of the plants with silk emergence of at least 0.5 inches. Growing Degree Units are calculated by the Barger Method as shown in the HEATP10 definition. 
     HEATS90 
     The number of GDU&#39;s required for an inbred or hybrid to have approximately 90 percent of the plants with silk emergence of at least 0.5 inches. Growing Degree Units are calculated by the Barger Method as shown in the HEATP10 definition. 
     MDMV A   
     Maize Dwarf Mosaic Virus strain A. The corn is rated on a 1-9 scale with a &#34;1&#34; being very susceptible, and a &#34;9&#34; being very resistant.* 
    
     MDMV B   
     Maize Dwarf Mosaic Virus strain B. This is rated on a 1-9 scale with a &#34;1&#34; being very susceptible and a &#34;9&#34; being very resistant.* 
    
     MOISTURE 
     The average percentage grain moisture of an inbred or hybrid at harvest time. 
     NLB 
     Northern Leaf Blight (Exserohilum turcicum) disease rating. This is rated on a 1-9 scale with a &#34;1&#34; being very susceptible, and a &#34;9&#34; being very resistant.* 
    
     PCT TILLER 
     The total number of tillers per plot divided by the total number of plants per plot. 
     PLANT 
     This term includes plant cells, plant protoplasts, plant cell tissue cultures from which corn plants can be regenerated, plant calli, plant clumps, and plant cells that are intact in plants or parts of plants, such as embryos, pollen, flowers, kernels, ears, cobs, leaves, husks, stalks, roots, root tips, anthers, silk and the like. 
     PLANT HEIGHT 
     The distance in centimeters from ground level to the base of the tassel peduncle. 
     RM 
     Predicted relative maturity based on the moisture percentage of the grain at harvest. This rating is based on a known set of checks and utilizes standard linear regression analyses and is referred to as the Minnesota Relative Maturity Rating System. 
     SHED 
     The volume of pollen shed by the male flower rated on a 1-9 scale where a &#34;1&#34; is a very light pollen shedder, a &#34;4.5&#34; is a moderate shedder, and a &#34;9&#34; is a very heavy shedder. If the Table(s) 3 have reduced the 1-9 shed scale to a 1-3 shed scale then any shed on Table 3 can be multiplied by 3 to reach the 1-9 shed scale. 
     SLB 
     Southern Leaf Blight (Bipolaris maydis) disease rating. This is rated on a 1-9 scale with a &#34;1&#34; being very susceptible, and a &#34;9&#34; being very resistant.* 
    
     TWT 
     The measure of the weight of grain in pounds for a one bushel volume adjusted for percent grain moisture. 
     VIGOR 
     Visual rating of 1 to 9 made 2-3 weeks post-emergence where a &#34;1&#34; indicates very poor early plant development, and a &#34;9&#34; indicates superior plant development. 
     WARM GERM 
     A measurement of seed germination under ideal (warm, moist) conditions. Data is reported as percent of seeds germinating. 
     YIELD (YLD) 
     Actual yield of grain at harvest adjusted to 15.5% moisture. Measurements are reported in bushels per acre. 
     % DROPPED EARS (DE) 
     The number of plants per plot which dropped their primary ear divided by the total number of plants per plot. 
     % LRG FLAT 
     Percentage by weight of shelled corn that passes through a 26/64 inch round screen and a 14/64 inch slot screen, but does not pass through a screen with 20.5/64 inch round openings. 
     % LRG ROUND 
     Percentage by weight of shelled corn that passes through a 26/64 inch round screen, but does not pass through a 14/64 inch slot screen or a screen with 20.5/64 inch round openings. 
     % MED FLAT 
     Percentage by weight of shelled corn that passes through a 20.5/64 inch round screen and a 13/64 inch slotted screen, but does not pass through a screen with 17/64 inch round openings. 
     % MED ROUND 
     Percentage by weight of shelled corn that passes through a 20.5/64 inch round screen, but does not pass through a 13/64 inch slot screen or a screen with 17/64 inch round openings. 
     % SML FLAT 
     Percentage by weight of shelled corn that passes through a 17/64 inch round screen and a 12/64 inch slotted screen, but does not pass through a screen with 15/64 inch round openings. 
     % SML ROUND 
     Percentage by weight of shelled corn that passes through a 17/64 inch round screen, but does not pass through a 12/64 inch slotted screen or a screen with 15/64 inch round openings. 
     % ROOT LODGE (RL) 
     Percentage of plants per plot leaning more that 30 degrees from vertical divided by total plants per plot. 
     % STALK LODGE (SL) 
     Percentage of plants per plot with the stalk broken below the primary ear node divided by the total plants per plot. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     ZS1202 can be used as a female or a male line due to its pollen shed and seed production abilities. This ZS1202 line evidences good general combining ability and specific combining ability with all types of males. This line makes big robust hybrids. 
     The inbred has shown uniformity and stability within the limits of environmental influence for all the traits as described in the Variety Description Information (Table 1) that follows. Most of the data in the Variety Description information was collected at Slater, Iowa. 
     The inbred has been self-pollinated for a sufficient number of generations to give inbred uniformity. During plant selection in each generation, the uniformity of plant type was selected to ensure homozygosity and phenotypic stability. The line has been increased in isolated farmland environments with data on uniformity and agronomic traits being observed to assure uniformity and stability. No variant traits have been observed or are expected in ZS1202. 
     The best method of producing the invention, ZS1202 which is substantially homozygous, is by planting the seed of ZS1202 which is substantially homozygous and self-pollinating or sib pollinating the resultant plant in an isolated environment, and harvesting the resultant seed or the resultant pollen. 
     
                                           TABLE 1__________________________________________________________________________          ZS1202          VARIETY DESCRIPTION INFORMATION          #1 Type: Dent          #2 Region Best Adapted: Central and east northern regionsINBRED ZS1202__________________________________________________________________________# 3 MATURITYDAYS    HEATUNITS79  1493     FROM PLANTING TO 50% OF PLANTS IN SILK78  1474     FROM PLANTING TO 50% OF PLANTS IN POLLEN 7           FROM 10% TO 90% POLLEN SHED#4  PLANTDATA 4           ANTHOCYANIN OF BRACE ROOTS: 1 = ABSENT 2 = FAINT 3 =        MODERATE 4 = DARK#5  LEAFCOLOR/DATA 3/DARK GREEN        LEAF COLOR **MUNSELL CODE-5GY 3/4 6           LEAF SHEATH PUBESCENCE (1 = NONE TO 9 = PEACH FUZZ) 5           MARGINAL WAVES (1 = NONE TO 9 = MANY) 4           LONGITUDINAL CREASES (1 = NONE TO 9 = MANY)#6  TASSELCOLOR/DATA 4           POLLEN SHED (0 = STERILE TO 9 = HEAVY SHEDDER) 7/YELLOW    ANOTHER COLOR **MUNSELL CODE-5Y 8/1002 w/17      GLUME COLOR **MUNSELL CODE-5GY 6/6 w/ 5R 3/4 STRIPES 2           BAR GLUME: 1 = ABSENT 2 = PRESENT#7A EAR (UNHUSKED DATA)COLOR/DATA 7/YELLOW    SILK COLOR (3 DAYS AFTER EMERGE) **MUNSELL CODE-5Y 7/8 w/ a        tint of pink 3/DARK GREEN        FRESH HUSK (25 DAYS AFTER 50% SILK) **MUNSELL CODE-5GY 5/622/TAN       DRY HUSK COLOR (65 DAYS AFTER 50% SILK **MUNSELL CODE-2.5Y        8/4 1           POSITION OF EAR AT DRY HUSK: 1 = UPRIGHT 2 = HORIZONTAL 3 =        PENDENT 5           HUSK TIGHTNESS (1 = VERY LOOSE TO 9 = VERY TIGHT) 2           HUSK EXTENSION AT HARVEST: 1 = EXPOSED EAR 2 = 8 CM 3 = 8-10        CM 4 = &gt;10 CM#7B EAR (HUSKED DATA)DATA 1           KERNEL ROWS: 1 = INDISTINCT 2 = DISTINCT 2           ROW ALIGNMENT: 1 = STRAIT 2 = SLIGHT CURVE 3 = SPIRAL 2           EAR TAPPER: 1 = STRAIT 2 = AVERAGE 3 = EXTREME#8  KERNEL (DRY)COLOR/DATA 1           ALEURONE COLOR PATTERN: 1 = HOMO 2 = SEG 8/YELLOW-ORANGE        ALEURONE COLOR **MUNSELL CODE-2.5Y 8/10 8/YELLOW-ORANGE        HARD ENDOSPERM COLOR **MUNSELL CODE-7.5YR 6/10 3           ENDOSPERM TYPE 7/YELLOW    CROWN COLOR **MUNSELL CODE-2.5Y 8/10#9  COBCOLOR14/RED       COB COLOR **MUNSELL CODE-10R 6/8__________________________________________________________________________COLOR CHOICES (Use in conjunction with Munsell color code to describe allcolor choices01 = Light Green       06 = Pale Yellow                  11 = Pink 16 = Pale Purple                                       21 = Buff02 = Medium Green       07 = Yellow                  12 = Light Red                            17 = Purple                                       22 = Tan03 = Dark Green       08 = Yellow-Orange                  13 = Cherry Red                            18 = Colorless                                       23 = Brown04 = Very Dark Green       09 = Salmon                  14 = Red  19 = White 24 = Bronze05 = Green-Yellow       10 = Pink-Orange                  15 = Red &amp; White                            20 = White Capped                                       25 = Variegated (Describe)                                       26 = Other (Describe)__________________________________________________________________________#10                        N   MEAN  STD   T-STAT PROB  95%__________________________________________________________________________                                                   CIEAR HEIGHT(CM)             15  87.80 9.10  37.38  0.0000                                                   (83.20,92.40)LENGTH OF PRIMARY EAR LEAF(CM)                      15  91.00 5.88  59.95  0.0000                                                   (88.02,93.98)WIDTH OF PRIMARY EAR LEAF(CM)                      15  9.20  0.49  72.30  0.0000                                                   (8.95,9.45)TOP EAR INTERNODE(CM)      15  14.53 1.11  50.73  0.0000                                                   (13.97,15.09)DEGREE OF LEAF ANGLE       15  30.40 6.49  18.14  0.0000                                                   (27.12,33.68)# OF EARS PER PLANT        15  1.80  0.41  16.84  0.0000                                                   (1.59,2.01)# OF LEAVES ABOVE TOP EAR  15  5.87  0.35  64.57  0.0000                                                   (5.69,6.04)# OF PRIMARY LATERAL TASSEL BRANCHES                      15  7.93  1.39  22.15  0.0000                                                   (7.23,8.64)PLANT HEIGHT(CM)           15  183.1 9.56  74.19  0.0000                                                   (178.3,188.0)TASSEL LENGTH(CM)          15  43.80 2.81  60.41  0.0000                                                   (42.38,45.22)TASSEL BRANCH ANGLE        15  24.13 6.65  14.05  0.0000                                                   (20.77,27.50)# OF TILLER PER PLANTS     15  0.00  0.00               (0.00,0.00)WEIGHT PER 100 KERNELS(GM) 15  34.22 1.48  89.85  0.0000                                                   (33.47,34.97)EAR LENGTH(CM)             15  15.56 0.86  70.00  0.0000                                                   (15.12,16.00)EAR WEIGHT(GM)             15  109.5 21.18 20.02  0.0000                                                   (98.79,120.2)# OF KERNEL ROWS           15  12.13 0.52  91.00  0.0000                                                   (11.87,12.39)COB DIAMETER AT MID-POINT(MM)                      15  25.40 0.72  137.2  0.0000                                                   (25.04,25.76)EAR DIAMETER AT MID-POINT(MM)                      15  41.69 1.48  109.3  0.0000                                                   (40.95,42.44)KERNEL LENGTH(MM)          15  11.05 0.49  88.16  0.0000                                                   (10.80,11.29)KERNEL THICKNESS(MM)       15  5.45  0.60  35.00  0.0000                                                   (5.15,5.76)KERNEL WIDTH(MM)           15  8.87  0.53  65.29  0.0000                                                   (8.60,9.13)% ROUND KERNELS(SHAPE GRADE)                      15  65.73 10.09 25.23  0.0000                                                   (60.63,70.84)SHANK LENGTH               15  8.93  1.89  18.33  0.0000                                                   (7.97,9.88)__________________________________________________________________________#11 DISEASE RESISTANCE -           Common corn rust = 3.8           Northern leaf blight = 2           Gray leaf spot = 5           Maize dwarf mosaic virus strain B = 1#12 The parent of ZS1202 is Holden&#39;s Inbred # 136. There is no comparablesame location data for the other parent.Other comparable inbreds are A632, PVP# 9000067, and PVP# 8200063.__________________________________________________________________________ 
    
     The Munsell code is a reference book of color which is known and used in the industry and by persons with ordinary skill in the art of plant breeding. 
     The purity and homozygosity of inbred ZS1202 is constantly being tracked using isozyme genotypes as shown in Table 2. 
     Isozyme Genotypes for ZS1202 
     Isozyme data were generated for inbred corn line ZS1202 according to procedures known and published in the art. The data in Table 2 gives the electrophoresis data on ZS1202. 
     
                                           TABLE 2__________________________________________________________________________ELECTROPHORESIS RESULTS FOR ZS1202INBRED ACP1     ACP4         ADH MDH1                 MDH2                     PGD1                         PGD2                             PH1                                PGM IDH2__________________________________________________________________________ZS1202 33  55  22  22  11  11  11  22 22  22__________________________________________________________________________ 
    
     Inbred and Hybrid Performance of ZS1202 
     The traits and characteristics of inbred corn line ZS1202 are listed to compare with other inbreds and/or in hybrid combination. ZS1202 data shows the characteristics and traits of importance, giving a snapshot of ZS1202. 
     Table 3A shows a comparison between ZS1202 and one of its parents Holden&#39;s Inbred #136. ZS1202 has significantly higher seedling vigor than does its parent Holden&#39;s Inbred #136. ZS1202 has higher yield and lower grain moisture at harvest than does Holden&#39;s Inbred #136. ZS1202 flowers significantly earlier than its parent across all pollination and silking data. ZS1202 reaches heat peek with significantly fewer heat units than does Holden&#39;s Inbred #136. ZS1202 has significantly lower germination under warm testing conditions than does Holden&#39;s Inbred #136. 
     
                                           TABLE 3A__________________________________________________________________________PAIRED INBRED COMPARISON DATA__________________________________________________________________________                      PCT  PLANT   EAR         EAR   PCTYEAR   INBRED        VIGOR   EMERGE                      TILLER                           HEIGHT  HEIGHT  SHED                                               QUALITY                                                     BARREN__________________________________________________________________________OVERALL  ZS1202        7.3     82.8       193.9   84.2    1.8 2.3  Holden&#39;s        6.0     81.9       175.7   64.8    1.8 2.7  Inbred #136  # EXPTS        3       3          3       3       2   3  DIFF  1.3     0.9        18.2    19.5    0.0 0.3  PROB  0.057             ***                0.915      0.016 **                                   0.020 **    0.423__________________________________________________________________________YEAR   INBRED        HEATP10 HEATP50 HEATP90 HEATS10  HEATS50 HEATS90__________________________________________________________________________OVERALL  ZS1202        1247    1286    1340    1309     1341    1379  Holden&#39;s        1321    1356    1411    1357     1396    1440  Inbred #136  # EXPTS        3       3       3       3        3       3  DIFF  73      69      71      48       55      60  PROB  0.003 * 0.025 **                        0.033 **                                0.059 ***                                         0.044 **                                                 0.096 ***__________________________________________________________________________                       BL   % ROOT                                 % STALK                                       % DROPPEDYEAR   INBRED        HEATPEEK HEATBL                       MOIST                            LODGE                                 LODGE EARS    MOISTURE                                                     YIELD__________________________________________________________________________OVERALL  ZS1202        1190     2558  28.5                    9.5   67.3  Holden&#39;s        1272     2591  27.5                    9.7   59.5  Inbred #136  # EXPTS        3        1     1                       3     3  DIFF  83       34    1.0                     0.2   7.8  PROB  0.012  **                              0.876__________________________________________________________________________        WARM    COLD % LRG   % LRG  % MED % MED                                               % SML % SMLYEAR   INBRED        GERM    GERM ROUND   FLAT   ROUND FLAT ROUND FLAT__________________________________________________________________________OVERALL  ZS1202        95.8    89.2 26.0    22.0   27.8  20.0 2.5   1.1  Holden&#39;s        97.5    89.8 5.2     3.7    42.8  30.7 8.8   7.4  Inbred #136  # EXPTS        3       3    3       3      3     3    3     3  DIFF  1.7     0.7  20.8    18.3   15.1  10.6 6.3   6.3  PROB  0.063             ***                0.625                     0.007 * 0.008                                  * 0.235__________________________________________________________________________ 
    
     Table 3B compares ZS1202 with A632. ZS1202 has better yield by 25 bushels and has lower grain moisture at harvest than does A632. ZS1202 has significantly more seedling vigor and is a taller plant with higher ear placement than is inbred A632. ZS1202 has significantly lower warm germination results in testing than does A632. ZS1202 and A632 flower at similar numbers of heat units. 
     
                                           TABLE 3B__________________________________________________________________________PAIRED INBRED COMPARISON DATA__________________________________________________________________________                      PCT  PLANT    EAR       EAR   PCTYEAR   INBRED        VIGOR   EMERGE                      TILLER                           HEIGHT   HEIGHT                                          SHED                                              QUALITY                                                    BARREN__________________________________________________________________________OVERALL  ZS1202        7.3     82.8       193.9    84.2  1.8 2.3  A632  4.5     79.8       166.8    73.2  1.8 2.7  # EXPTS        3       3          3        3     2   3  DIFF  2.8     3.0        27.1     11.0  0.0 0.3  PROB  0.060             ***                0.688      0.073 ***                                    0.119     0.423__________________________________________________________________________YEAR   INBRED        HEATP10 HEATP50 HEATP90 HEATS10 HEATS50 HEATS90__________________________________________________________________________OVERALL  ZS1202        1247    1286    1340    1309    1341    1379  A632  1261    1303    1354    1317    1356    1397  # EXPTS        3       3       3       3       3       3  DIFF  13      17      14      8       15      18  PROB  0.558   0.442   0.554   0.726   0.604   0.603__________________________________________________________________________                     BL   % ROOT                                % STALK                                      % DROPPEDYEAR   INBRED        HEATPEEK               HEATBL                     MOIST                          LODGE LODGE EARS    MOISTURE                                                     YIELD__________________________________________________________________________OVERALL  ZS1202        1190   2558  28.5                     9.5    67.3  A632  1155   2383  33.0                     10.1   41.9  # EXPTS        3      1     1                        3      3  DIFF  35     175   4.5                      0.6    25.4  PROB  0.226                                 0.484__________________________________________________________________________        WARM   COLD % LRG   % LRG  % MED  % MED                                               % SML % SMLYEAR   INBRED        GERM   GERM ROUND   FLAT   ROUND  FLAT ROUND FLAT__________________________________________________________________________OVERALL  ZS1202        95.8   89.2 26.0    22.0   27.8   20.0 2.5   1.1  A632  98.5   86.8 6.4     4.9    51.5   25.3 8.7   2.4  # EXPTS        3      3    3       3      3      3    3     3  DIFF  2.7    2.3  19.6    17.0   23.7   5.2  6.2   1.3  PROB  0.026             **               0.504                    0.026 **                            0.001                                 * 0.014                                        **__________________________________________________________________________ 
    
     Table 3C is an inbred comparison between ZS1202 and PVP #8200063. ZS1202 has significantly better seedling vigor than does PVP #8200063 as well as having better emergence of plants. ZS1202 is a significantly taller plant with significantly higher ear placement than PVP #8200063. ZS1202 reaches all three rated levels of pollination (HeatP10-90) significantly earlier than does PVP #8200063. ZS1202 has lower grain moisture at harvest and higher yield than PVP #8200063. 
     
                                           TABLE 3C__________________________________________________________________________PAIRED INBRED COMPARISON DATA__________________________________________________________________________                    PCT  PLANT    EAR          EAR   PCTYEAR   INBRED        VIGOR  EMERGE                    TILLER                         HEIGHT   HEIGHT   SHED                                               QUALITY                                                     BARREN__________________________________________________________________________OVERALL  ZS1202        7.3    82.8      193.9    84.2     1.8 2.3  PVP   4.7    76.9      159.6    72.0     1.5 2.5  #8200063  # EXPTS        3      3         3        3        2   3  DIFF  2.7    5.9       34.3     12.3     0.3 0.2  PROB  0.026             **               0.381     0.061 ***                                  0.065 ***                                           0.500                                               0.423__________________________________________________________________________YEAR   INBRED        HEATP10  HEATP50  HEATP90  HEATS10                                          HEATS50                                                 HEATS90__________________________________________________________________________OVERALL  ZS1202        1247     1286     1340     1309   1341   1379  PVP   1294     1338     1380     1305   1358   1393  #8200063  # EXPTS        3        3        3        3      3      3  DIFF  46       52       40       4      17     14  PROB  0.002  * 0.011  **                          0.001  * 0.516  0.188  0.501__________________________________________________________________________                       BL   % ROOT                                 % STALK                                       % DROPPEDYEAR   INBRED        HEATPEEK HEATBL                       MOIST                            LODGE                                 LODGE EARS    MOISTURE                                                     YIELD__________________________________________________________________________OVERALL  ZS1202        1190     2558  28.5                    9.5   67.3  PVP   1253     2442  28.5                    10.1  63.9  #8200063  # EXPTS        3        1     1                       3     3  DIFF  64       116   0.0                     0.5   3.4  PROB  0.017  **                              0.288__________________________________________________________________________        WARM  COLD  % LRG   % LRG   % MED % MED                                               % SML % SMLYEAR   INBRED        GERM  GERM  ROUND   FLAT    ROUND FLAT ROUND FLAT__________________________________________________________________________OVERALL  ZS1202        95.8  89.2  26.0    22.0    27.8  20.0 2.5   1.1  PVP   95.8  95.8  2.7     2.2     35.7  30.6 14.4  9.9  #8200063  # EXPTS        3     3     3       3       3     3    3     3  DIFF  0.0   6.7   23.3    19.8    8.0   10.6 11.9  8.9  PROB  1.000 0.233 0.004 * 0.009 * 0.349__________________________________________________________________________ 
    
     Table 3D compares ZS1202 with PVP #9000067 and shows ZS1202 has lower grain moisture at harvest and higher grain yield by 10 bushels per acre. ZS1202 is a significantly taller plant with higher ear placement than PVP #9000067. ZS1202 evidences more seedling vigor but less seedling emergence than does PVP #9000067. ZS1202 reaches 10% and 50% pollination significantly earlier than PVP #9000067 and reaches 90% earlier but not significantly earlier. This indicates ZS1202 has an extended pollen shed period in comparison to PVP #9000067. ZS1202 reaches Heat Peek significantly earlier than does PVP #9000067. ZS1202 has better seedling germination results in both warm and cold testing. 
     
                                           TABLE 3D__________________________________________________________________________PAIRED INBRED COMPARISON DATA__________________________________________________________________________                   PCT   PLANT   EAR          EAR   PCTYEAR   INBRED        VIGOR             EMERGE                   TILLER                         HEIGHT  HEIGHT  SHED QUALITY                                                    BARREN__________________________________________________________________________OVERALL  ZS1202        7.5  81.6        191.0   81.8    1.8  2.2  PVP   6.4  86.0        153.2   62.5    1.9  2.1  #9000067  # EXPTS        5    5           5       5       4    5  DIFF  1.1  4.4         37.8    19.3    0.1  0.1  PROB  0.180             0.435       0.006 * 0.017 **                                         0.718                                              0.374__________________________________________________________________________YEAR   INBRED        HEATP10   HEATP50  HEATP90                                  HEATS10                                         HEATS50 HEATS90__________________________________________________________________________OVERALL  ZS1202        1271      1311     1370   1331   1367    1408  PVP   1324      1365     1413   1345   1385    1428  #9000067  # EXPTS        5         5        5      5      5       5  DIFF  53        54       43     14     18      20  PROB  0.011   **                  0.014  **                           0.138  0.251  0.267   0.268__________________________________________________________________________                       BL   % ROOT                                 % STALK                                       % DROPPEDYEAR   INBRED        HEATPEEK HEATBL                       MOIST                            LODGE                                 LODGE EARS    MOISTURE                                                     YIELD__________________________________________________________________________OVERALL  ZS1202        1213     2558  28.5                    9.8   69.9  PVP   1250     2449  32.5                    10.1  59.8  #9000067  # EXPTS        5        1     1                       5     5  DIFF  37       109   4.0                     0.3   10.0  PROB  0.055 ***                              0.342__________________________________________________________________________        WARM  COLD % LRG   % LRG  % MED   % MED                                               % SML % SMLYEAR   INBRED        GERM  GERM ROUND   FLAT   ROUND   FLAT ROUND FLAT__________________________________________________________________________OVERALL  ZS1202        96.1  90.4 26.8    22.5   27.0    19.3 2.5   1.1  PVP   83.6  75.8 6.6     11.2   36.9    33.9 6.7   3.4  #9000067  # EXPTS        5     5    5       5      5       5    5     5  DIFF  12.5  14.6 20.2    11.3   9.9     14.7 4.1   2.3  PROB  0.244 0.146                   0.000 * 0.001                                * 0.003 *__________________________________________________________________________ 
    
     Table 4 shows the GCA (general combining ability) estimates of ZS1202 compared with the GCA estimates of the other inbreds. The estimates show the general combining ability is weighted by the number of experiment/location combinations in which the specific hybrid combination occurs. The interpretation of the data for all traits is that a positive comparison is a practical advantage. A negative comparison is a practical disadvantage. The general combining ability of an inbred is clearly evidenced by the results of the general combining ability estimates. This data compares the inbred parent in a number of hybrid combinations to a group of &#34;checks&#34;. The check data is from other companies&#39; hybrids, particularly the leader in the industry and ICI Seeds&#39; commercial products and pre-commercial hybrids which were grown in the same sets and locations. 
     
                                           TABLE 4A__________________________________________________________________________  HYBRID  #     N  YM GI YLD                    MOIST                         % SL                             % RL                                 % DE                                     RM__________________________________________________________________________ZS1202 115   1635            0.1              -1.5                 -1.4                    0.4  -0.2                             -0.7                                 0.0 110Holden&#39;s   22    737           -0.2              -0.8                 -3.5                    0.1   0.4                              0.5                                 0.1 124Inbred #136__________________________________________________________________________ 
    
     Table 4A shows ZS1202 crossed to 115 different inbreds and Holden&#39;s Inbred #136, its parent, crossed to 22 inbreds. ZS1202 in hybrid combination shows an advantage for yield by moisture compared to Holden&#39;s Inbred #136 which has a disadvantage in yield by moisture. ZS1202 has a better rating for yield and a better advantage rating for moisture at 0.4 than Holden&#39;s Inbred #136 at 0.1 moisture. ZS1202 has more tendency to have stalk lodging and root lodging than Holden&#39;s Inbred #136 but ZS1202 drops less ears than does Holden&#39;s Inbred #136. 
     
                                           TABLE 4B__________________________________________________________________________   HYBRID   #     N  YM GI YLD                     MOIST                          % SL                              % RL                                  % DE                                      RM__________________________________________________________________________ZS1202  115   1635            0.1               -1.5                  -1.4                     0.4  -0.2                              -0.7                                  0.0 110A632     13    213            -0.3               -2.9                  -4.4                     -0.3 0.1 -0.6                                  0.0  98PVP #8200063    87   2446            0.0               -1.9                  -2.8                     0.5  -0.2                              -0.3                                  0.0 105PVP #9000067   156   7371            0.0               -1.9                  -5.0                     0.8  0.1 0.4 0.1 108__________________________________________________________________________ 
    
     Table 4B compares ZS1202 in random hybrid combinations with A632, PVP #8200063, and PVP #9000067 in random combinations. ZS1202 has an advantage in yield by moisture when compared to the ratings of A632, PVP #8200063, and PVP #9000067. ZS1202 also shows the best GI index rating of the four inbreds in the table. ZS1202 has a negative 1.4 yield advantage compared with PVP #8200063 and PVP #9000067 which have a negative 1.9 advantage and A632 which has a negative 2.9 advantage. ZS1202 has a moisture advantage over A632 but less moisture advantage than either PVP #8200063 or PVP #9000067. ZS1202 has the most tendency to root lodge. As is evidenced by the GI index, the inbred ZS1202 has the best, most consistent inbred package to bring into the hybrid combination. 
     
                       TABLE 5______________________________________YIELD RESPONSEHYBRID    YIELD______________________________________ZS1202/Inbred     84     107     130   153   176   199Environment     75     100     125   150   175   200______________________________________ 
    
     Table 5 shows the yield response of ZS1202 in hybrid combination in comparison with the plants in the environment around it at the same location. ZS1202 in hybrid combination yields well in low yielding environments, in medium yield environments the ZS1202 hybrid continues to out yield the competition. In high yielding environments, the ZS1202 hybrid tends to show less aggressive yields compared to the environment. 
     
                                           TABLE 6A__________________________________________________________________________HYBRID SUMMARYZS1202/INBREDPERFORMANCE DATAHYBRID   N FI GI YM YLD                  MST                     % SL                         % RL                             % DE                                 TWT__________________________________________________________________________RE 8777  62      -5.1         -0.1            -0.4               2.8                  -2.2                     -0.7                         -1.3                             0.1 1.2RE 8692IT    63      3.6         3.9            0.4               11.8                  -0.1                     -0.9                         -1.2                             0.0 -0.9RE 8612  62      2.1         1.6            0.3               5.7                  0.2                     -0.5                         -1.4                             0.2 1.3RE 8574  70      10.3         2.1            1.0               8.9                  3.6                     -1.8                         -1.3                             0.2 1.4__________________________________________________________________________ 
    
     Table 6A shows in positive numbers the advantage the ZS1202 hybrid has over four commercially available ICI Seeds&#39; hybrids. ZS1202 hybrid compares the least favorably with 8777. 8777 is adapted to a slightly different zone of the Corn Belt; however, ZS1202 in hybrid comparison has better yield results and less dropped ears than 8777. ZS1202 in hybrid combination has a better G index rating, yield by moisture than 8692IT. 
     Additionally, ZS1202 has 11.8 advantage in yield over 8692IT. ZS1202 has similar drop ear tendency as 8692IT and a slight disadvantage in its tendency to stalk and root lodge. ZS1202 in hybrid combination has the competitive advantage over 8612 and 8574 in all indexes and in the yield and moisture categories except stalk and root lodging. 
     
                                           TABLE 6B__________________________________________________________________________HYBRID SUMMARYZS1202/INBREDAGRONOMIC DATA              EAR   PLANT      STAY HEAT-                                         HEAT-HYBRID N ESTAND         VIGOR              HEIGHT                    HEIGHT                          PCTTIL                               GREEN                                    P50  S50  HEATBL__________________________________________________________________________8777  8 -3.2  -0.1 5.5   3.9   0.8  -1.0 44.2 58.1 30.68692IT 8 -0.7  0.3  6.8   7.8   -2.6 -0.8 8.5  31.0 5.08512  8 -0.7  0.2  2.5   0.1   -1.6 0.8  -14.3                                         3.3  27.48574  8 -2.0  0.1  3.2   4.0   -0.0 -1.7 -8.1 2.9  -18.8__________________________________________________________________________ 
    
     Table 6B shows the advantages and disadvantages generated by comparison of the agronomic data of the four hybrids with the ZS1202 hybrid. These advantages are shown in Table 6A. ZS1202 has a lower emerged early plant stand count than the four hybrids. However, ZS1202 shows seedling vigor advantage over three hybrids and a slight disadvantage to 8777. Clearly, ZS1202 is a taller plant with higher ear placement than the other four hybrids. In all instances, the ZS1202 hybrid reaches 50% silking earlier than the other four hybrids. ZS1202 reaches 50% pollination earlier than 8777 and 8692IT and later than 8612 and 8574. ZS1202 reaches HeatBL with fewer heat units than 8777, 8692IT, and 8612. 
     
                                           TABLE 7A__________________________________________________________________________HYBRID    TESTS          GI ADV YLD                    ADV MOIST                             ADV SL                                   ADV RL ADV DE ADV__________________________________________________________________________ZS1202/Inbred   RE     407  181              2  170.6                    6.4*                        19.8 0.6*                                 2.5                                   0.1 1.8                                          -1.3                                              0.0                                                 -0.08692IT  RE     407  179    164.2  20.4     2.6   0.6    0.0ZS1202/Inbred   ST     224  180             -3  166.4                    -2.6*                        20.1 -0.1                                 2.3                                   -0.0                                       1.6                                          -0.6                                              0.1                                                 -0.18692IT  ST     224  183    169.1  20.0     2.3   1.0    0.0__________________________________________________________________________ The following conditions are met: 1. The comparison was made in at least two of the three years. 2. FIVE OR MORE 1994 STRIP TESTS/RESEARCH HAVE THE COMPARISON. 3. THE 92-94 MOIST DIFFERENCE IS BETWEEN -4 AND 4. NOTE: The * beside the MOIST ADV and the YIELD ADV denotes significance a the .10 level. 
    
     Table 7A shows ZS1202/Inbred and 8692IT in both research testing and in experimental strip plots across years. ZS1202 hybrid evidenced significantly better yield and significantly lower moisture in the research plots than 8692IT. ZS1202/Inbred showed better resistance to stalk lodging and similar tendency to drop ears as did 8692IT. 
     In the experimental strip test data, ZS1202 in hybrid combination showed a significantly lower yield than 8692IT and approximately equivalent moisture and stalk lodging. 
     
                                           TABLE 7B__________________________________________________________________________HYBRID    TESTS          GI ADV YLD                    ADV MOIST                             ADV SL                                   ADV RL ADV DE ADV__________________________________________________________________________ZS1202/Inbred   RE     52   167             2   146.6                    8.2*                        22.0 -0.3                                 3.0                                   -0.8                                       3.4                                          -1.6                                              0.0                                                 -0.08644    RE     52   165    138.4  21.7     3.1   1.8    0.0__________________________________________________________________________ The following conditions are met: 1. The comparison was made in at least two of the three years. 2. FIVE OR MORE 1994 STRIP TESTS/RESEARCH HAVE THE COMPARISON. 3. THE 92-94 MOIST DIFFERENCE IS BETWEEN -4 AND 4. NOTE: The * beside the MOIST ADV and the YIELD ADV denotes significance a the .10 level. 
    
     Table 7B compares ZS1202/Inbred with 8644 in research trials. In the research plots, ZS1202 in hybrid combination significantly out yielded 8644 and had slightly higher moisture. 
     
                                           TABLE 8A__________________________________________________________________________  ECB1        ECB2          ECB TUNNELLING  VISUAL        # YEARS              STAMDARD                      # YEARS                            cm OF    # YEARSINBRED RATING        TESTED              RATING  TESTED                            TUNNELLING                                     TESTED__________________________________________________________________________ZS1202 4.6   2     4.1     2     54.2     2Holden&#39;s  4.9   8     4.4     8     17.5     8Inbred #136__________________________________________________________________________ 
    
     Table 8A compares ZS1202 as an inbred with its inbred parent Holden&#39;s Inbred #136 for ECB resistance to the first and second brood. Holden&#39;s Inbred #136 has slightly higher ECBI and ECBII ratings than does ZS1202. 
     
                       TABLE 8B______________________________________INBRED       CCR    GLS       MDMV.sub.B                                NLB______________________________________A632         4.3    3.2       3.7    5.2PVP #8200063 4.4    3.3       3.6    5.1PVP #9000067 2.5    3         2      4.3ZS0193       6      3         3      7ZS1202       3.8    5         1      2Holden&#39;s     4      3.9       2.8    5.4Inbred #136______________________________________ 
    
     Table 8B compares the pathology data of ZS1202 with its parent and the other comparable inbreds. ZS1202 evidences a much better gray leaf spot rating than the other comparable inbreds. 
     The inbred ZS1202 can be employed as the female or the male plant in a hybrid production field. This inbred is a medium tall line with moderate ear height. ZS1202 has a dark green color during the growing season with long slender ears. 
     In hybrid combination, ZS1202 carries good yield for moisture characteristics into the hybrid. ZS1202 shows good performance in heat and moisture stress and tends to carry this trait into its hybrids. This inbred has good early vigor which it carries into its hybrids. Additionally, this inbred adapts well from South Dakota eastward, when in hybrid combination. At least one ZS1202 hybrid may be pH sensitive. This inbred has fairly good general combining and specific combining ability for yield, with most male lines. ZS1202 is a versatile line. This ZS1202 inbred makes robust hybrids. 
     The foregoing is set forth by way of example and is not intended to limit the scope of the invention. 
     This invention also is directed to methods for producing a corn plant by crossing a first parent corn plant with a second parent corn plant wherein the first or second parent corn plant is an inbred corn plant from the line ZS1202. Further, both first and second parent corn plants can come from the inbred corn line ZS1202. A variety of breeding methods can be selected depending on the mode of reproduction, the trait, the condition of the germplasm. Thus, any such methods using the inbred corn line ZS1202 are part of this invention: selfing, backcrosses, hybrid production, crosses to populations, and the like. 
     Various culturing techniques known to those skilled in the art, such as haploid, transformation, and a host of other conventional and unconventional methods are within the scope of the invention. All plants and plant cells produced using inbred corn line ZS1202 are within the scope of this invention. The invention encompasses the inbred corn line used in crosses with other, different, corn inbreds to produce (F1) corn hybrid seeds and plants with the characteristics that make good hybrids. This invention includes cells which upon growth and differentiation produce corn plants having the physiological and morphological characteristics of the inbred line ZS1202. 
     Duncan, from at least 1985-1988 produced literature on plant regeneration from callus. Both inbred and hybrid callus have resulted in regenerated plants at excellent efficiency rates. Somatic embryogenesis has been performed on various maize tissue such as glume which before the 1980&#39;s was considered unuseable for this purpose. The prior art clearly teaches the regeneration of plants from various maize tissues. 
     Stauffer Chemical, the predecessor to Zeneca Ag Chem, in European Patent Application, publication 160,390, incorporated herein by reference describes tissue culture of corn. Corn tissue culture procedures are also described in the literature as early as 1982. 
     A deposit of at least 2500 seeds of the inbred seed of of this invention is maintained by ICI Seeds, 2369 330th Street, Slater, Iowa 50244. Access to this deposit will be available during the pendency of this application to the Commissioner of Patents and Trademarks and persons determined by the Commissioner to be entitled thereto upon request. All restrictions on availability to the public of such material are removed upon issuance of the patent. The Applicant made a deposit of at least 2500 seeds of Inbred Corn Line ZS1202 with the American Type Culture Collection (ATCC), located at 12301 Parklawn Drive, Rockville, Md. 20852. The ATCC Accession No. is 97629. The seeds were deposited with the ATCC on Jun. 26, 1996 and were taken from the inbred seed deposit maintained by ICI Seeds. The ATCC deposit will be maintained in that depository, which is a public depository, for a period of 30 years, or 5 years after the last request, or for the effective life of the patent, whichever is longer, and will be replaced if it becomes nonviable during that period. Additionally, Applicant has satisfied all the requirements of 37 C.F.R. §§1.801-1.809, including providing an indication of the viability of the sample. 
     Inbreds designated MBS are available from Mike Brayton Seed in Iowa. Inbreds designated SGI are available from Seed Genetic Inc. in New Jersey. Information on the ZS designations may be available from the PVP office. 
     Accordingly, the present invention has been described with some degree of particularity directed to the preferred embodiment of the present invention. It should be appreciated, though, that the present invention is defined by the following claims contrued in light of the prior art so that modifications or changes may be made to the preferred embodiment of the present invention without departing from the inventive concepts contained herein.