Reactions of Sweet Corn Hybrids to Prevalent Diseases

(sumarized for named varieties rated for disease resistance to maize dwarf mosaic virus, mdm)

Revised October 2000

Jerald K. Pataky

Department of Crop Sciences,

University of Illinois, Urbana, IL 61801

Common rust (Puccinia sorghi), northern leaf blight - NLB (Exserohilum turcicum), Stewart's bacterial wilt (Erwinia stewartii), maize dwarf mosaic - MDM (MDM viruses), southern leaf blight - SLB (Bipolaris maydis), anthracnose leaf blight - ALB (Colletotrichum graminicola), southern rust (Puccinia polysora) and gray leaf spot - GLS (Cercospora zeae-maydis) are endemic diseases of sweet corn grown in North America. Reactions to these diseases vary among commercial sweet corn hybrids. Since 1984, nearly 2,200 hybrids have been evaluated for disease reactions in nurseries at the University of Illinois at Urbana-Champaign.. Hybrids were classified as resistant (R), moderately resistant (MR), moderate (M), moderately susceptible (MS), and susceptible (S) based on standard deviations from trial means (z-scores), separations based on multiple comparison tests (BLSD), and multivariate clustering procedures. This type of classification produces statistically “overlapping” groups without clear-cut differences between classes (e.g., the hybrid with the least severe symptoms in the MR class does not differ significantly from the hybrid with the most severe symptoms in the R class); however, a consistent response of a hybrid over several trials gives a reasonable estimate of the disease reaction of that hybrid. These reactions are relative because a hybrid is classified from R to S based on its response in comparison to all other hybrids being evaluated.

Results of the annual disease nurseries have been reported each year in the Midwestern Vegetable Variety Trial Report. This article summarizes the disease reactions of 624 commercially-available hybrids that that have been evaluated in UIUC nurseries since 1984. The summary includes 117 sugary hybrids (109 yellow, 2 bi-color and 6 white), 185 sugary enhancer hybrids (66 yellow, 83 bi-color, 34 white, and 2 red), 315 shrunken-2 hybrids (154 yellow, 108 bi-color, 52 white and 1 multi-color), and 7 brittle hybrids (5 yellow, 1 bi-color and 1 white).

General information

Details about specific trials are reported annually in the Midwestern Vegetable Variety Trial Report. Plants usually were inoculated with P. sorghi, E. turcicum, E. stewartii, C. graminicola, B. maydis, P. polysora, or C. zeae-maydis to insure uniform disease pressure. Evaluations of reactions to MDM and systemic Stewart’s wilt were based on natural infection when disease pressure was relatively uniform.

In this summary, hybrids are grouped by: i) endosperm phenotype (sugary, sugary enhancer, shrunken, and brittle); ii) kernel color (yellow, bi-color, white, and other), and iii) alphabetically by hybrid name. The table includes: seed source (SC - company which entered the hybrid in the nursery), endosperm type (ET), kernel color (KC), relative maturity (RM) from 1 to 5 as reported by each seed company (where 1 = first early, 2 = second early, 3 = mid-season, 4 = main season, and 5 = full season), hybrid name, and reactions to diseases: common rust, NLB, Stewart’s wilt, MDM, SLB, ALB, southern rust, and GLS. Disease reactions are averaged over all years a hybrid was evaluated and are presented on a 0 to 9 scale, where: 1 = resistant, 3 = moderately resistant, 5 = moderate, 7 = moderately susceptible, and 9 = susceptible. Hybrids with Rp-reactions to common rust are noted with an asterisk. The number of years a hybrid was evaluated for each disease is noted with a superscript. For example, the reaction of Jubilee to common rust is listed as 5 ¹⁵indicating that the average rust reaction of Jubilee is moderate (5) relative to all other sweet corn hybrids and this estimate is based on 15 years of evaluation of Jubilee in UIUC trials for common rust.

Interpretation of disease reactions

Resistance and susceptibility are the two extremes of a continuum of host reactions to diseases. Resistance measures the ability of the host to reduce the growth, reproduction, or disease-producing abilities of the pathogen, thus resulting in less severe symptoms. Major genes for resistance, such as Rp, Ht, or Mdm1, can prevent or substantially limit disease development if specific virulence is not present in pathogen populations. Hybrids with major gene resistance usually are identified from specific phenotypes.

Major gene resistance may be ineffective when specific virulence occurs. For example, a biotype of the P. sorghi virulent on hybrids with the Rp1-D resistance gene was widespread in the North America in 1999 and 2000 (8,10). Rust pustules were observed on all Rp-resistant hybrids in the disease nursery in 2000, but severity was usually lower on Rp-resistant hybrids than on non-Rp hybrids probably because P. sorghi biotypes with virulence against Rp1-D comprised a relatively low percentage of the rust population. Since common rust occurred on all Rp-resistant hybrids in the nursery in 2000, hybrids with Rp-resistance are noted with an asterisk, and the rust reaction of Rp-resistant hybrids is given for trials in which Rp-resistance was not completely effective (i.e., 2000). For example, the rust reaction of Bonus is listed as 2* ¹. The asterisk indicates that Bonus was Rp-resistant in previous trials, but it was rated R/MR (2) in 2000 when Rp-resistance was not entirely effective. If a disease reaction is not given for an Rp-hybrid (e.g., Bold rated .^* ³), the hybrids was evaluated only in nurseries in which Rp-resistance was completely effective ( i.e., all nurseries prior to 2000) and the number of years the hybrid was evaluated is noted as the superscript.

If hybrids do not have effective major gene resistance, disease reactions often range from partially resistant to susceptible. Since our nurseries have included most of the sweet corn hybrids available commercially, our ratings reflect the disease reactions of a hybrid relative to all sweet corn.

Disease reactions of resistant (R) hybrids are listed as 1. These were among the best hybrids evaluated in our trials in the past 17 years. Those rated 9 are susceptible (S) and were among the worst. The moderately resistant ratings (3) included hybrids with disease reactions that were better than average. The moderately susceptible ratings (7) include hybrids that are worse than average. Moderate ratings (5) are hybrids with average reactions. Classification of hybrid reactions can vary among years (e.g., some hybrids may have been classified M in one trial and MR or MS in another trial due to random variation). Average reactions based on at least three years of data are probably more accurate estimates than those based on one or two years.

Symptoms will occur on hybrids rated R, but the amount of the disease will be less than the amount on hybrids rated MR to S. The effects of diseases on yield are related to hybrid reactions to diseases which affect disease severity (1,2,3,4,5,6,7,9).

References

1. Kerns, M. R., and J. K. Pataky. 1997. Reactions of sweet corn hybrids with resistance to maize dwarf mosaic. Plant Disease 81:460-464.

2. Pataky, J. K. 1987. Quantitative relationships between sweet corn yield and common rust, Puccinia sorghi. Phytopathology 77:1066-1071.

3. Pataky, J. K. 1992. Relationships between yield of sweet corn and northern leaf blight caused by Exserohilum turcicum. Phytopathology 82:370-375.

4. Pataky, J.K., and D.M. Eastburn. 1993. Using hybrid disease nurseries and yield loss studies to evaluate levels of resistance in sweet corn. Plant Disease 77:760-765.

5. Pataky, J. K., J. M. Headrick, and Suparyono. 1988. Classification of sweet corn hybrid reactions to common rust, northern leaf blight, Stewart’s wilt, and Goss’s wilt and associated yield reductions. Phytopathology 78:172-178.

6. Pataky, J. K., J. F. Murphy, and C. J. D’Arcy. 1990. Resistance to maize dwarf mosaic virus, severity of symptoms, titer of virus, and yield of sweet corn. Plant Disease 74:359-364.

7. Pataky, J. K., R. N. Raid, L. J. du Toit, and T. J. Schueneman. 1998. Disease severity and yield of sweet corn hybrids with resistance to northern leaf blight. Plant Disease 82:57-63.

8. Pataky, J. K., and W. F. Tracy. 1999. Widespread occurrence of common rust, caused by Puccinia sorghi, on Rp-resistant sweet corn in the midwestern United States. Plant Disease. 83:1177.

9. Suparyono and J. K. Pataky. 1989. Influence of host resistance and growth stage at the time of inoculation on Stewart’s wilt and Goss’s wilt development and sweet corn hybrid yield. Plant Disease 73:339-345.

10. Pate, M.C., J. K. Pataky, W. C. Houghton, and R. H. Teyker. 2000. First report of Puccinia sorghi virulent on sweet corn with the Rp1-D gene in Florida and Texas. Plant Disease 84:1154

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Yellow sugary

Rog su Y 5 Bonus 2* ¹ 5 ⁵ 1 ⁴ 1 ⁵ 6 ⁵ 3 ¹ 8 ² 4 ¹

Cr su Y 5 Conquest 2* ¹ 6 ³ 6 ³ 9 ⁴ 6 ³ . ^. 7 ¹ 6 ¹

HM su Y 3 Dynamo .* ³ 6 ³ 5 ² 4 ² 5 ³ . ^. 9 ² . ^.

Cr su Y 2 Earlivee 8 ⁸ 8 ⁷ 8 ⁷ 8 ⁴ 8 ⁵ 7 ³ . ^. . ^.

Asg su Y 4 El Toro 3* ¹ 7 ⁵ 4 ⁴ 2 ⁵ 4 ⁵ . ^. 9 ² 4 ¹

Cr su Y 4 Eliminator 5* ¹ 6 ⁸ 2 ⁷ 1 ⁵ 6 ⁷ 4 ³ 9 ² 6 ¹

Asg su Y 5 Esquire 2* ¹ 7 ⁵ 6 ⁴ 7 ⁵ 4 ⁵ . ^. 8 ² 4 ¹

Rog su Y 4 Jubilee 5 ¹⁵ 8 ¹⁵ 9 ¹⁶ 8 ⁵ 4 ⁷ 7 ⁵ 8 ² . ^.

HM su Y 4 Lumina .* ⁴ 8 ⁴ 8 ⁴ 9 ² 6 ³ 5 ² 9 ² . ^.

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Bi-color/White sugary

Cr su B 3 Honey & Cream 6 ⁶ 6 ⁶ 7 ⁶ 9 ⁵ 6 ⁵ 5 ³ 8 ² 6 ¹

Cr su B 1 Quickie 9 ⁹ 9 ⁸ 7 ⁹ 7 ⁵ 9 ⁶ 8 ³ 9 ² . ^.

Rog su W 5 Silver Queen 8 ⁴ 3 ⁵ 3 ⁶ 9 ¹ 5 ¹ 6 ³ 9 ¹ . ^.

Yellow sugary enhancer

Cr se Y 3 Bodacious 4 ¹² 5 ¹² 5 ¹³ 9 ⁵ 4 ⁸ 3 ³ 8 ² 6 ¹

Cr se Y 3 Bodacious R 3 ¹ 5 ¹ 4 ¹ 9 ² 2 ¹ . ^. . ^. . ^.

Asg se Y 4 Climax 2 ¹ 8 ¹ 2 ¹ 9 ² 1 ¹ . ^. . ^. . ^.

Rog se Y 4 Empire .* ⁴ 6 ⁵ 6 ⁴ 7 ² 3 ⁴ 5 ² 8 ² . ^.

Cr se Y 4 Incredible 3 ¹³ 5 ¹² 3 ¹² 9 ⁵ 5 ⁸ 6 ⁴ 7 ² 6 ¹

Cr se Y 4 Incredible R 3 ¹ 6 ¹ 3 ¹ 9 ² 2 ¹ . ^. . ^. . ^.

Cr se Y 4 Intrigue 2* ¹ 7 ³ 6 ³ 8 ⁴ 6 ³ . ^. 9 ¹ 6 ¹

Mesa se Y 5 Merlin 3 ⁷ 4 ⁷ 2 ⁷ 8 ⁵ 2 ⁶ 3 ¹ 6 ² 4 ¹

Cr se Y 4 Miracle 2 ¹⁵ 3 ¹⁵ 1 ¹⁶ 9 ⁵ 4 ⁸ 3 ⁵ 8 ² 4 ¹

Sen se Y 2 Seneca Arrow II 7 ² 5 ² 3 ² 9 ³ 4 ² . ^. . ^. 4 ¹

Sen se Y 1 Seneca Pronto 5 ² 5 ² 7 ² 9 ² 6 ² . ^. 6 ¹ 8 ¹

Cr se Y 2 Sugar Buns 5 ¹² 4 ¹¹ 6 ¹¹ 8 ⁵ 4 ⁸ 5 ³ 8 ² 6 ¹

HM se Y 1 Sweet Cheeks 9 ² 8 ² 7 ² 7 ² 5 ² . ^. 8 ² . ^.

HM se Y 1 Sweet Riser 6 ³ 6 ³ 6 ² 9 ² 4 ³ 1 ¹ 8 ² . ^.

Mesa se Y 5 Tablemaster 7 ² 5 ² 4 ² 7 ² 5 ² . ^. 5 ¹ 4 ¹

HM se Y 5 Topacio 3* ¹ 4 ⁷ 3 ⁷ 2 ⁵ 6 ⁷ 3 ¹ 8 ² 6 ¹

Mesa se Y 4 Tuxedo 3 ³ 2 ³ 2 ³ 9 ² 2 ³ . ^. . ^. . ^.

Mesa se Y 2 Welcome TSW 7 ¹ . ^. 5 ¹ 9 ² 4 ¹ . ^. . ^. . ^.

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Bi-color sugary enhancer

Cr se B 3 Ambrosia 5 ⁹ 5 ⁸ 1 ⁹ 9 ⁵ 6 ⁷ 6 ³ 8 ² 4 ¹

Mesa se B 2 Bon Apetit TSW 7 ¹ 5 ¹ 4 ¹ 9 ² 3 ¹ . ^. . ^. . ^.

Cr sb B 3 Bravado 5 ³ 6 ³ 4 ³ 9 ⁴ 4 ³ . ^. 7 ¹ 8 ¹

Mesa se B 4 Buckeye 6 ² 5 ² 2 ² 9 ³ 5 ² . ^. . ^. 4 ¹

Cr se B 2 D Artagnan 8 ⁹ 8 ⁹ 7 ¹¹ 9 ³ 8 ⁷ 5 ³ 9 ² 6 ¹

Cr se B 4 Delectable 3 ⁷ 4 ⁷ 4 ⁶ 9 ⁵ 3 ⁶ 6 ³ 8 ² 8 ¹

HM se B 3 Double Choice 4 ² 8 ² 6 ² 9 ² 8 ² . ^. 8 ² . ^.

Sdw se B 2 Ecstase II 6 ³ 4 ³ 6 ² 9 ² 7 ³ . ^. 8 ² . ^.

Mesa se B 5 Encore 5 ² 6 ² 2 ² 9 ³ 4 ² . ^. . ^. 4 ¹

Cr se B 1 Fleet 5 ³ 9 ³ 6 ³ 7 ⁴ 4 ³ . ^. 9 ¹ . ^.

Mesa se B 4 Friendship 6 ¹ 3 ¹ 3 ¹ 9 ² 6 ¹ . ^. . ^. . ^.

Mesa se B 3 Luscious TSW 7 ¹ 4 ¹ 3 ¹ 9 ² 4 ¹ . ^. . ^. . ^.

Cr se B 3 Mystique 6 ³ 3 ³ 3 ³ 9 ⁴ 5 ³ . ^. 9 ¹ 6 ¹

Mesa se B 3 Parfait 5 ² 5 ² 4 ² 9 ² 6 ² . ^. 9 ¹ 8 ¹

Mesa se B 4 Precious Gem 5 ² 4 ² 4 ² 9 ³ 4 ² . ^. . ^. 3 ¹

Sen se B 1 Seneca Arrowhead 5 ³ 7 ³ 6 ³ 8 ³ 5 ³ . ^. 8 ² 8 ¹

Sen se B 4 Seneca Dancer 4 ⁵ 5 ⁵ 5 ⁴ 9 ³ 4 ⁴ 4 ² 6 ² 4 ¹

Sen se B 4 Seneca Nation 5 ³ 3 ³ 1 ³ 8 ⁴ 5 ³ . ^. 7 ¹ 6 ¹

Sen se B 2 Seneca Spring 5 ³ 5 ³ 4 ³ 8 ⁴ 5 ³ . ^. 9 ¹ 8 ¹

Sen se B 2 Seneca Tomahawk 4 ³ 4 ³ 6 ³ 7 ³ 4 ³ . ^. 7 ² 6 ¹

Asg se B 4 Sensor 3 ⁸ 4 ⁸ 5 ¹⁰ 9 ⁴ 3 ⁶ 3 ¹ 6 ¹ 6 ¹

HS se B 2 Sir Prize 8 ⁴ 6 ⁴ 7 ⁴ 9 ⁵ 4 ³ . ^. 7 ² . ^.

Asg se B 4 Sunset 4 ⁶ 6 ⁶ 6 ⁶ 9 ⁵ 2 ⁵ 4 ² 7 ² 4 ¹

HM sb B 2 Sweet Chorus 6 ³ 7 ³ 7 ² 4 ² 6 ³ . ^. 8 ² . ^.

Cr se B 2 Trinity 7 ⁵ 7 ⁵ 6 ⁴ 8 ⁵ 6 ⁵ . ^. 8 ² 8 ¹

Asg se B 4 Wizard 5 ⁴ 7 ⁴ 8 ⁴ 8 ⁵ 4 ⁴ . ^. 7 ² 6 ¹

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

White sugary enhancer

Cr se W 4 Argent 4 ⁹ 3 ⁸ 2 ⁹ 9 ⁵ 3 ⁷ 5 ³ 6 ² 6 ¹

Mesa se W 4 Avalanche 8 ¹ 4 ¹ 5 ¹ 9 ² 4 ¹ . ^. . ^. . ^.

HM se W 4 Brilliance 4 ² 5 ² 4 ² 9 ² 5 ² . ^. 8 ² . ^.

Asg se W 1 Celebration 7 ⁴ 5 ⁴ 4 ⁴ 7 ⁴ 7 ³ 5 ² 9 ¹ 4 ¹

Mesa se W 4 Cloud Nine TSW 5 ² 4 ² 2 ² 9 ³ 5 ² . ^. . ^. 6 ¹

Asg se W 3 Fantasia 4 ⁵ 8 ⁵ 8 ⁴ 7 ² 6 ⁵ 5 ¹ 7 ² . ^.

Cr se W 3 Frosty 6 ⁴ 6 ⁴ 6 ⁴ 7 ⁵ 4 ⁴ . ^. 8 ² 8 ¹

Mesa se W 4 Imaculata 6 ¹ 3 ¹ 3 ¹ 9 ² 4 ¹ . ^. . ^. . ^.

Sen se W 2 Seneca SEnsation 4 ⁵ 5 ⁵ 5 ⁴ 9 ⁵ 2 ⁵ . ^. 7 ² 6 ¹

Sen se W 2 Seneca Snowshoe 7 ³ 4 ³ 2 ³ 6 ² 9 ² 7 ¹ 9 ¹ 8 ¹

Rog se W 3 Silver King 3 ⁴ 5 ⁴ 5 ³ 9 ⁴ 3 ⁴ 3 ¹ 9 ¹ 6 ¹

Rog se W 2 Silver Princess 6 ⁴ 6 ⁴ 5 ⁴ 8 ⁵ 4 ⁴ . ^. 8 ² 6 ¹

HM se W 3 Sweet Ice 7 ³ 6 ³ 5 ² 9 ² 3 ³ 1 ¹ 9 ² . ^.

Red sugary enhancer

Asg sesu R 5 Sweet Scarlet 5 ² 6 ² 9 ² 9 ³ 3 ² . ^. . ^. 4 ¹

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Yellow shrunken

Cr sh2 Y 5 Assure 3* ¹ 5 ⁴ 8 ⁴ 8 ⁵ 2 ⁴ . ^. 8 ² 4 ¹

HM sh2 Y 4 Bandit .* ³ 8 ³ 7 ² 2 ² 4 ³ 5 ¹ 8 ² . ^.

Asg sh2 Y 5 Brigadier 6 ⁵ 3 ⁵ 8 ⁵ 9 ³ 4 ⁴ 4 ² 7 ² 4 ¹

Asg sh2 Y 4 Brut 6 ³ 4 ³ 6 ³ 8 ⁴ 3 ³ . ^. 7 ¹ 6 ¹

Asg sh2 Y 3 Challenger 6 ⁹ 3 ⁹ 4 ¹¹ 9 ⁴ 3 ⁷ 2 ³ 6 ¹ 6 ¹

Cr sh2 Y 4 Crisp n Sweet 710 6 ¹³ 2 ¹² 3 ¹³ 9 ⁵ 2 ⁸ 2 ⁵ 9 ² 6 ¹

Cr sh2 Y 4 Crisp n Sweet 710A 6 ⁷ 2 ⁷ 4 ⁶ 9 ⁵ 2 ⁶ 3 ³ 7 ² 3 ¹

Cr sh2 Y 4 Crisp n Sweet 710ARR 3 ¹ 1 ¹ . ^. 9 ² 1 ¹ . ^. . ^. . ^.

Rog sh2 Y 3 Cronus 3* ¹ 5 ⁴ 5 ⁴ 7 ⁵ 6 ⁴ . ^. 8 ² 4 ¹

HM sh2 Y 4 Day Star 6 ⁷ 1 ⁷ 4 ⁶ 8 ⁵ 2 ⁶ 2 ³ 7 ² 2 ¹

IFS sh2 Y 3 Early Illini 8 ² 5 ² 6 ² 9 ² 5 ² . ^. 9 ¹ 4 ¹

Asg sh2 Y 3 Endeavor 6 ⁷ 3 ⁷ 5 ⁶ 9 ⁵ 2 ⁶ 2 ³ 6 ² 4 ¹

Sdw sh2 Y 4 Envy 3* ¹ 2 ² 5 ² 9 ³ 2 ² . ^. 6 ¹ . ^.

Sdw sh2 Y 5 Flagship II 5* ¹ 4 ⁴ 4 ³ 9 ⁴ 2 ⁴ . ^. 6 ¹ 4 ¹

IFS sh2 Y 5 Florida Staysweet 8 ¹³ 3 ¹³ 3 ¹⁴ 9 ² 3 ⁶ 3 ⁵ 8 ² . ^.

Sak sh2 Y 5 Honey 420 6 ² 3 ² 5 ² 9 ² 1 ² . ^. 7 ² . ^.

Cr sh2 Y 4 Marvel 5* ¹ 5 ⁶ 7 ⁵ 8 ⁵ 2 ⁵ 4 ² 7 ² 8 ¹

Cr sh2 Y 4 Missouri 6 ⁴ 4 ⁴ 2 ³ 9 ⁴ 3 ⁴ . ^. 6 ¹ 6 ¹

HM sh2 Y 5 Morning Star 5* ¹ 1 ⁵ 6 ⁴ 5 ⁵ 1 ⁵ . ^. 5 ² 2 ¹

Rog sh2 Y 3 Prime Plus 3* ¹ 2 ⁵ 3 ⁴ 9 ⁵ 6 ⁵ 1 ¹ 9 ² 4 ¹

Rog sh2 Y 3 Primetime 6 ⁵ 2 ⁵ 3 ⁴ 9 ³ 8 ⁴ 5 ² 6 ¹ . ^.

Asg sh2 Y 3 Punchline 7 ⁷ 3 ⁷ 3 ⁶ 9 ⁴ 4 ⁶ 3 ³ 6 ¹ 6 ¹

Rog sh2 Y 4 Royal Sweet .* ⁵ 6 ⁵ 7 ⁴ 9 ² 6 ³ 6 ³ 7 ¹ 6 ¹

Sdw sh2 Y 3 Saturn 5 ⁴ 6 ⁴ 3 ³ 9 ³ 4 ³ 3 ² 6 ¹ . ^.

Cr sh2 Y 3 Samson 5* ¹ 6 ³ 6 ³ 7 ⁴ 5 ³ . ^. 9 ¹ 6 ¹

Asg sh2 Y 5 Shimmer 3* ¹ 2 ⁷ 5 ⁷ 9 ⁵ 2 ⁶ 2 ³ 5 ² 4 ¹

Asg sh2 Y 4 Stetson 5* ¹ 5 ⁵ 5 ⁴ 9 ⁵ 2 ⁵ . ^. 7 ² 6 ¹

AC sh2 Y 2 Summer Sweet 6800 R 6* ¹ 5 ² 7 ² 9 ³ 3 ² . ^. . ^. 6 ¹

AC sh2 Y 3 Summer Sweet 7100 7 ³ 7 ³ 5 ³ 8 ³ 7 ² 5 ² . ^. 4 ¹

AC sh2 Y 4 Summer Sweet 7630 6 ⁹ 2 ⁸ 2 ⁹ 9 ⁵ 2 ⁸ 4 ² 8 ² 4 ¹

AC sh2 Y 4 Summer Sweet 7710 7 ¹⁰ 2 ¹⁰ 2 ¹² 8 ⁵ 2 ⁸ 4 ³ 8 ² 4 ¹

AC sh2 Y 3 Summer Sweet 8100 4 ³ 3 ³ 5 ³ 9 ⁴ 1 ³ . ^. 6 ¹ 3 ¹

Sak sh2 Y 5 Super Honey Bantam 5 ¹ 7 ¹ 9 ¹ 9 ² 2 ¹ . ^. . ^. . ^.

Rog sh2 Y 4 Supersweet Jubilee 6 ⁹ 7 ⁹ 9 ⁷ 8 ⁵ 3 ⁶ 7 ² 8 ² 4 ¹

HM sh2 Y 4 Suregold 5* ¹ 7 ⁴ 6 ³ 3 ⁴ 3 ⁴ . ^. 0 ¹ 4 ¹

HM sh2 Y 3 Sweetear 6 ⁴ 6 ⁵ 5 ⁵ 9 ² 4 ³ 5 ¹ . ^. . ^.

HM sh2 Y 4 Ultimate 6 ⁹ 2 ⁸ 2 ⁹ 8 ⁵ 2 ⁷ 4 ³ 7 ² 4 ¹

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Bi-color shrunken

HM sh2 B 3 Candy Corner .* ³ 8 ³ 6 ³ 3 ³ 4 ³ 7 ¹ 8 ² 4 ¹

IFS sh2 B 3 Early Illini BC 7 ² 5 ² 6 ² 9 ² 5 ² . ^. 9 ¹ 6 ¹

IFS sh2 B 2 Fortune BC 2 ² 5 ² 6 ² 5 ² 4 ² . ^. 8 ¹ 6 ¹

IFS sh2 B 1 Fresh Start 8 ² 6 ² 5 ² 9 ² 6 ² . ^. 9 ¹ 4 ¹

Asg sh2 B 4 Hollywood 5* ¹ 6 ² 6 ² 9 ³ 5 ² . ^. . ^. 4 ¹

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

Bi-color shrunken (continued)

Asg sh2 B 4 Madonna 6 ³ 6 ³ 6 ² 9 ² 5 ³ . ^. 9 ² . ^.

IFS sh2 B 3 Majesty 7 ³ 3 ³ 6 ³ 9 ² 4 ³ 4 ² 8 ¹ 4 ¹

Sak sh2 B 5 Petercorn 6 ⁶ 5 ⁶ 7 ⁴ 9 ² 3 ⁴ 6 ² 7 ² . ^.

Cr sh2 B 5 Phenomenal 6 ¹⁵ 5 ¹⁵ 5 ¹⁶ 9 ⁵ 5 ⁸ 5 ⁵ 7 ² 4 ¹

Sen sh2 B 3 Seneca Lone Wolf 8 ⁴ 7 ⁴ 9 ³ 9 ² 4 ³ 5 ² 9 ¹ 6 ¹

Sdw sh2 B 4 Starship II 3* ¹ 3 ² 5 ² 9 ³ 1 ² . ^. 6 ¹ . ^.

AC sh2 B 4 Summer Sweet 8102 5 ⁸ 2 ⁷ 3 ⁸ 9 ⁴ 1 ⁷ 1 ¹ 7 ¹ 4 ¹

AC sh2 B 4 Summer Sweet 8102R 3 ¹ 3 ¹ 4 ¹ 9 ² 1 ¹ . ^. . ^. . ^.

Rog sh2 B 3 Tethys 3 ¹ 5 ¹ 5 ¹ 9 ² 4 ¹ . ^. . ^. . ^.

HM sh2 B 5 Twin Star 5* ¹ 1 ³ 4 ³ 2 ⁴ 2 ³ . ^. 7 ¹ 4 ¹

Sak sh2 B 5 Yumeno corn 3* ¹ 4 ² 7 ² 8 ³ 4 ² . ^. . ^. 4 ¹

Reactions of sweet corn hybrids in the University of Illinois Disease Nursery

Common Stewart’s Southern

SC ET KCRM Hybrid rust NLB wilt MDM SLB ALB rust GLS

White shrunken

Rog sh2 W 3 Boreal 5* ¹ 3 ⁴ 4 ⁴ 9 ⁵ 7 ⁴ . ^. 7 ² 4 ¹

Asg sh2 W 5 Dreamer 5 ⁴ 6 ⁴ 7 ⁴ 8 ⁵ 4 ⁴ . ^. 8 ² 6 ¹

Asg sh2 W 5 Even Sweeter 6 ⁹ 5 ⁹ 5 ¹⁰ 9 ² 4 ⁶ 5 ¹ 8 ² . ^.

IFS sh2 W 1 First Class 9 ² 7 ² 6 ² 9 ² 6 ² . ^. 9 ¹ 6 ¹

IFS sh2 W 2 First Snow 8 ² 6 ² 6 ² 7 ² 5 ² . ^. 9 ¹ 6 ¹

Cr sh2 W 5 How Sweet It Is 6 ¹² 5 ¹¹ 4 ¹¹ 8 ⁵ 4 ⁷ 3 ⁵ 7 ² 4 ¹

HM sh2 W 3 Ice Queen .* ³ 7 ³ 4 ² 3 ² 4 ³ 7 ¹ 6 ¹ 4 ¹

IFS sh2 W 3 Majesty W 8 ² 5 ² 6 ² 9 ² 4 ² . ^. 9 ¹ 4 ¹

Sak sh2 W 5 Millennium 3 ¹ 3 ¹ 1 ¹ 2 ² 1 ¹ . ^. . ^. . ^.

IFS sh2 W 2 Nova 9 ² 6 ² 8 ² 9 ² 5 ² . ^. 9 ¹ 6 ¹

Sen sh2 W 3 Seneca Sugarburst 6 ³ 8 ³ 9 ² 9 ² 2 ³ 5 ¹ 6 ¹ 6 ¹

HM sh2 W 3 Silver Dollar 8 ² 3 ² 4 ² 5 ¹ 6 ¹ 5 ² 9 ¹ . ^.

IFS sh2 W 4 Snow Storm 5 ³ 5 ³ 7 ³ 9 ³ 3 ³ . ^. 8 ² 4 ¹

HM sh2 W 4 Snow White 9 ⁹ 7 ¹⁰ 7 ¹⁰ 4 ⁵ 3 ⁸ 7 ³ 8 ² 6 ¹

Asg sh2 W 4 Sugar Bowl 6 ⁵ 4 ⁵ 7 ⁴ 9 ⁴ 2 ⁴ 5 ² 7 ² . ^.

AC sh2 W 4 Summer Sweet 7631 6 ⁶ 2 ⁶ 3 ⁵ 8 ⁵ 2 ⁵ 4 ² 7 ² 4 ¹

AC sh2 W 3 Summer Sweet 781 Ultra 6 ⁷ 3 ⁷ 3 ⁶ 9 ⁵ 4 ⁶ 5 ³ 9 ² 4 ¹

Rog sh2 W 3 Vail 7 ³ 2 ³ 5 ² 9 ² 4 ³ . ^. 8 ¹ 4 ¹

Sdw sh2 W 3 White Saturn 6 ¹ 6 ¹ 4 ¹ 9 ² 6 ¹ . ^. . ^. . ^.

Rog sh2 W 3 Windham 5* ¹ 7 ³ 7 ³ 9 ⁴ 3 ³ . ^. 9 ¹ 4 ¹

ET = endosperm type: su = sugary, se = sugary enhancer, sesu = heterozygous sugary enhancer, sb = sweet breed, sh2 = shrunken-2, bt1 = brittle.

KC = kernel color: B = bicolor, W = white, Y = yellow, R = red

RM = relative maturity estimates from seed source: 1 – first early

2 – second early

3 – mid-season

4 – main season

5 – full season

6 – sub-temperate or later

SC = seed company: AC = Abbott & Cobb, Asg = Asgrow (Seminis), Cht = Charter Seed, Cr = Crookham, DM = Del Monte, GG = Green Giant, HM = Harris Moran, HS = Harris Seeds, IFS = Illinois Foundation Seeds, JS = Johnny’s Selected, LSC = Liberty Seed, Mesa = Mesa Maize, Rog = Rogers Novartis, Sak = Sakata, Sdw = SeedWay (Agway), Sen = Seneca Hybrids/Peto Brand (Seminis), SnRv = Snowy River, UHA = University of Hawaii

Rxn = classification of hybrid disease reaction: * - Rp reaction (see text)

1 – resistant

3 - moderately resistant

5 – moderate

7 – moderately susceptible

9 – susceptible

Superscript – number of years each hybrid was evaluated for each disease