scholarly journals Development of Gibberella Ear Rot on Processing Sweet Corn Hybrids Over an Extended Period of Harvest

Plant Disease ◽  
2007 ◽  
Vol 91 (2) ◽  
pp. 171-175 ◽  
Author(s):  
J. N. Nordby ◽  
J. K. Pataky ◽  
D. G. White
Keyword(s):  
Rating Scale ◽  
Sweet Corn ◽  
Extended Period ◽  
Gibberella Zeae ◽  
Ear Rot ◽  
Corn Hybrids ◽  
Gibberella Ear Rot ◽  
Relative Response ◽  
Harvest Dates ◽  
The Difference

Gibberella ear rot, caused by Gibberella zeae, has increased in prevalence recently on lateseason processing sweet corn grown in North America. Little information is available about the development of Gibberella ear rot on processing sweet corn hybrids over extended periods of harvest. In five trials from 2003 to 2005, 12 processing sweet corn hybrids were inoculated with G. zeae and evaluated for severity of Gibberella ear rot on sequential harvest dates from 19 to 27 days after midsilk. Ear rot severity was assessed using a rating scale based on the percentage of kernels with visible symptoms of G. zeae colonization including kernel rot and mycelial growth. Severity ranged from 1.6 to 47.8% over the five trials. None of the hybrids was highly resistant to Gibberella ear rot, although some appeared to be less susceptible. Gibberella ear rot was less severe on three hybrids (GH 2690, GG 147, and Sprint) and more severe on three hybrids (GG 42, GG 145, and Jubilee). Other hybrids had moderate levels of ear rot or responses that varied among years. The relative response of hybrids did not change substantially during the extended period of harvest; however, the rate at which Gibberella ear rot developed on hybrids differed in 2003 and 2005 as reflected by a significant hybrid by harvest interaction. The interaction was primarily the result of Gibberella ear rot developing more severely on susceptible hybrids than on the less susceptible hybrids. The difference in Gibberella development could be exploited to limit losses due to this disease under certain circumstances. If a sweet corn processor had several fields ready to harvest at the same time, and some fields were planted with hybrids that are more susceptible while other fields were planted with hybrids that are less susceptible, losses due to Gibberella ear rot might be minimized by harvesting the most susceptible hybrids first. Other hybrids that might be best suited for early or late harvest can be identified from Gibberella ear rot ratings 28 days after silk channel inoculation at the midsilk growth stage.

scholarly journals Reactions of Processing Sweet Corn Hybrids to Gibberella Ear Rot

Plant Disease ◽  
1999 ◽  
Vol 83 (2) ◽  
pp. 176-180 ◽  
Author(s):  
Lindsey J. du Toit ◽  
Jerald K. Pataky
Keyword(s):  
United States ◽  
Growth Stage ◽  
Sweet Corn ◽  
Gibberella Zeae ◽  
The Other ◽  
Ear Rot ◽  
Corn Hybrids ◽  
Gibberella Ear Rot ◽  
Injection Method ◽  
Coefficients Of Variation

Gibberella ear rot has increased in prevalence recently on late-season processing sweet corn grown in the Midwestern United States. Little information is available about the reactions of hybrids currently grown for processing. A total of 52 processing hybrids were evaluated in 1996 and 1997 for reactions to Gibberella zeae following one of two methods of inoculation: inserting an infested toothpick or injecting a spore suspension in the silk channel 7 days after the mid-silk growth stage. Ratings of ear rot severity ranged from 2.4 to 8 on a scale of 1 to 9. Severity of ear rot differed among hybrids, but none of the hybrids was highly resistant, nor did the hybrids display a great degree of variation for reaction to G. zeae. Severity of ear rot was consistently lower for cvs. Sprint and HMX 5372 than for the other hybrids. Ear rot ratings also were lower for cvs. GH 1834 and GH 2690 in three of four comparisons. Severity of ear rot was consistently higher for cv. GH 2628 in all comparisons and for cvs. Empire, Excalibur, GG 42, GH 1861, Jubilee, Rival, and WSS 3680 in three of four comparisons. Ranks of some hybrids changed between inoculation methods, years, or both, but most hybrids were ranked similarly in at least three of four comparisons. Coefficients of variation were approximately 5% higher for the injection method of inoculation in 1996 than for the other trials. The toothpick method of inoculation required less labor and ranked hybrids as consistently or more consistently than the injection method.

scholarly journals Reciprocal Differences in Sugary × Sugary Enhancer Sweet Corn Hybrids

2008 ◽  
Vol 133 (6) ◽  
pp. 777-782 ◽  
Author(s):  
Bernardo Ordás ◽  
Rosa A. Malvar ◽  
Amando Ordás ◽  
Pedro Revilla
Keyword(s):  
Sweet Corn ◽  
Agronomic Traits ◽  
Sugar Content ◽  
Favorable Effect ◽  
Reciprocal Effects ◽  
Quality Traits ◽  
Seed Parent ◽  
Corn Hybrids ◽  
Reciprocal Differences ◽  
The Difference

Reciprocal effects in sugary × sugary enhancer hybrids of sweet corn (Zea mays L.) have been only reported for sugar content and in a very limited number of hybrids and have not been determined for agronomic traits. By evaluating 34 sugary × sugary enhancer hybrids with reciprocals in three environments, the main objectives of this work were, for agronomic and quality traits, to determine the presence or absence of reciprocal differences in the sugary × sugary enhancer hybrids, to study the interest of using sugary inbreds as seed parents of the sugary × sugary enhancer hybrids, and to determine if reciprocal differences are interacting with different genetic backgrounds and different environments. For agronomic traits as emergence, early vigor, and silking date, significant (P ≤ 0.05) reciprocal differences were found in many of the sugary × sugary enhancer hybrids, but for quality traits, significant (P ≤ 0.05) reciprocal differences were only found in a few hybrids. The sugary lines as seed parents of the crosses tended to have on average a favorable effect on agronomic traits, but this was only considerable in some environmental conditions. The difference between the sugary and sugary enhancer lines as seed parent of the crosses was strongly influenced by the genetic background.

GIBBERELLA EAR ROT DEVELOPMENT AND ZEARALENONE AND VOMITOXIN PRODUCTION AS AFFECTED BY MAIZE GENOTYPE AND Gibberella zeae STRAIN

1983 ◽  
Vol 63 (4) ◽  
pp. 847-853 ◽  
Author(s):  
G. N. ATLIN ◽  
P. M. ENERSON ◽  
L. G. McGIRR ◽  
R. B. HUNTER
Keyword(s):  
Zea Mays L ◽  
Gibberella Zeae ◽  
Strain Effect ◽  
Ear Rot ◽  
Hybrid Strain ◽  
Corn Hybrids ◽  
Single Strain ◽  
Large Rank ◽  
Maize Genotype ◽  
Toxin Accumulation

In 1980, six corn hybrids were inoculated with each of six strains of G. zeae in order to determine whether hybrid-strain interactions occur with respect to ear rot and mycotoxin accumulation. A statistically significant interaction was observed for mold damage, but no large-rank reversals occurred. All six strains identified the same hybrid as being the most resistant. In 1981, three of the original six hybrids were tested with three new strains. No interaction was observed. Hybrids common to the two seasons maintained their relative ranking over years. Analyses for zearalenone and vomitoxin content were performed for both years. Toxin level was significantly correlated with percent mold damage in both years (r = 0.69 to r = 0.83). When covariance adjustment for mold level was performed, hybrids were found not to differ significantly for toxin accumulation in either year. A strain and hybrid × strain effect was observed only for zearalenone in 1980. These data indicate that a single strain should be adequate for resistance screening, and confirm the importance of reducing mold levels through breeding as a solution to the mycotoxin problem.Key words: Corn, maize, Zea mays L., ear mold, mycotoxins

Colonization of maize silks by Fusarium graminearum, the causative organism of gibberella ear rot

2007 ◽  
Vol 85 (4) ◽  
pp. 369-376 ◽  
Author(s):  
S. Shea Miller ◽  
Lana M. Reid ◽  
Linda J. Harris
Keyword(s):  
Fusarium Graminearum ◽  
Fluorescent Protein ◽  
Fungal Growth ◽  
Infection Process ◽  
Gibberella Zeae ◽  
Causative Organism ◽  
Ear Rot ◽  
Wild Type ◽  
Gibberella Ear Rot ◽  
Maize Silks

One of the most economically important diseases of maize in Canada is gibberella ear rot caused by Fusarium graminearum Schwabe (teleomorph = Gibberella zeae (Schw.) Petch). Understanding how the fungus becomes established will help in developing effective strategies to reduce the incidence of this disease. This study investigates the infection process of F. graminearum on maize silks using both a wild-type F. graminearum as well as a strain transformed with a gene from jellyfish to constitutively express green fluorescent protein. Immature ears of maize were inoculated in the field with wild-type F. graminearum and harvested at specific times post infection, and the silks were stained with Chlorazol Black E for examination. In addition, uninoculated ears were excised, placed on water agar in large Petri dishes, and the silks inoculated with a suspension of macroconidia of the transformed fungus. The progress of fungal growth was then monitored using microscopy. Germination of conidia was observed 4–6 h after inoculation. A variable period of random growth often followed, after which some of the hyphae would grow in more or less straight lines down the silk towards the cob (rachis), and ultimately infect the developing kernels. Access to the cob occurred in 7–9 d in susceptible genotypes and 12–15 d in resistant genotypes. The fungus could penetrate the ovary directly through the silk attachment point or, when the silk was growing over other kernels, the fungus could traverse from the silk to colonize interkernel spaces. Entry into the cob was either through the rachis surface via exterior growth between kernels, or into the rachis via the pedicel.

scholarly journals Effect of Water Supply on Spectral Traits and Their Relationship with the Productivity of Sweet Corns

Agronomy ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 63 ◽  
Author(s):  
Eszter Nemeskéri ◽  
Krisztina Molnár ◽  
Csaba Rácz ◽  
Attila Dobos ◽  
Lajos Helyes
Keyword(s):  
Sweet Corn ◽  
Carotenoid Content ◽  
Corn Hybrids ◽  
Carotene Content ◽  
Area Index ◽  
Stage Of Development ◽  
Total Carotenoid Content ◽  
Dry Conditions ◽  
The Difference ◽  
The Individual

Three super-sweet corn hybrids (Zea mays L. convar. saccharata) with different ripening characteristics were grown in three water supplies (regularly irrigated, deficit-irrigated, and unirrigated) to examine the spectral reflectance at leaf and canopy levels, leaf area index (LAI) during the stage of development and their relationship with the yield and nutritional quality. Under unirrigated conditions, the plant’s height, diameter, and weight of ears per plants, as well as total carotenoid content of kernels, decreased, SPAD values of leaves, normalized vegetation differential index (NDVI) and LAI were low. The difference in SPAD and LAI was higher between the hybrids during the silking than the tasseling period under water deficiency. Under unirrigated dry conditions, no correlation was found between SPAD, NDVI, and yield. Using deficit irrigation, SPAD measured during tasseling correlated closely with the individual husked ear and the final yields as well as the sugar and carotene contents of kernels. Under this condition, NDVI did not correlate with the yield, but LAI was correlated with the yield and its carotene content. Under deficit irrigated conditions, the 46 to 49 range of SPAD measured during tasseling predicted 23.5 to 26.7 t ha−1 depending on the hybrid, but this range predicted a yield lower by 6.4 to 10.1% during silking.

scholarly journals Uji Ketahanan beberapa Varietas Unggul Jagung terhadap Penyakit Gibberella dan Diplodia

Biosfera ◽  
2015 ◽  
Vol 32 (2) ◽  
pp. 103
Author(s):  
Soenartiningsih Soenartiningsih
Keyword(s):  
Block Design ◽  
Ear Rot ◽  
Corn Hybrids ◽  
Hybrid Corn ◽  
Gibberella Ear Rot ◽  
Randomized Block Design ◽  
Check Resistance ◽  
Rot Disease ◽  
Hybrid Maize ◽  
Corn Kernels

Gibberella and Diplodia ear rot is a disease that can damage the corn cobs and corn kernels resulting in lower quality and quantity of seed. The objective of the research are to find the varieties of corn which are resistant  the ear  rot disease Gibberella and Diplodia. This study was conducted in Limang Karo regency, North Sumatera, a randomized block design with three replications, each treatment comprised 4 rows and each row contained 25 plants with a spacing of 75 x 20 cm. The results showed 25 Hybrid maize tested against Gibberella ear rot there are 7 Hybrid corn hybrids that are resistant to ear rot  Kenia-2, NK33, Bima 3, Bima 10 Bima 12 Q, NEI-9008 and X8B649 (check resistance) and moderately resistance there are 9 hybrid that Kenia-3, DK979, NK22, P12, Gumarang, Srikandi putih, Lamuru and Sukmaraga  and 9 hybrid to ear rot disease were reacted susceptible and highly susceptible. Whereas from 25 Hybrid maize tested against Diplodia ear rot there are 6 Hybrid corn hybrids resistant to ear rot disease is Kenia - 2, NK33, Bima 3, Bima 12 Q, NEI-9008 and X8B649 (check resistance) while that is moderately resistancet there are 11 hybrid that is Kenia-3, DK979, NK22, P29, Bisi 2, P12, Bima 10, Gumarang, Srikandi putih, Lamuru and Sukmaraga, while 8 hybrid others were reacted susceptible and highly susceptible.

D-test: A New Test for Analyzing Scale Invariance Using Symbolic Dynamics and Symbolic Entropy

Methodology ◽  
2011 ◽  
Vol 7 (3) ◽  
pp. 88-95 ◽  
Author(s):  
Jose A. Martínez ◽  
Manuel Ruiz Marín
Keyword(s):  
Symbolic Dynamics ◽  
Scale Invariance ◽  
Rating Scales ◽  
Rating Scale ◽  
Marketing Research ◽  
Response Patterns ◽  
Measurement Scales ◽  
Improve Measurement ◽  
Entropy Measures ◽  
The Difference

The aim of this study is to improve measurement in marketing research by constructing a new, simple, nonparametric, consistent, and powerful test to study scale invariance. The test is called D-test. D-test is constructed using symbolic dynamics and symbolic entropy as a measure of the difference between the response patterns which comes from two measurement scales. We also give a standard asymptotic distribution of our statistic. Given that the test is based on entropy measures, it avoids smoothed nonparametric estimation. We applied D-test to a real marketing research to study if scale invariance holds when measuring service quality in a sports service. We considered a free-scale as a reference scale and then we compared it with three widely used rating scales: Likert-type scale from 1 to 5 and from 1 to 7, and semantic-differential scale from −3 to +3. Scale invariance holds for the two latter scales. This test overcomes the shortcomings of other procedures for analyzing scale invariance; and it provides researchers a tool to decide the appropriate rating scale to study specific marketing problems, and how the results of prior studies can be questioned.

Phytotoxic effect of deoxynivalenol and gibberella ear rot resistance of com

1995 ◽  
Vol 3 (5) ◽  
pp. 383-388 ◽  
Author(s):  
Françoise Cossette ◽  
J. David Miller
Keyword(s):  
Ear Rot ◽  
Gibberella Ear Rot ◽  
Phytotoxic Effect

scholarly journals Review of the efficacy of placebo in comparative clinical trials between typical and atypical antipsychotics

2009 ◽  
Vol 31 (1) ◽  
pp. 52-56 ◽  
Author(s):  
Irismar Reis de Oliveira ◽  
Paulo Menezes Nunes ◽  
Domingos Macedo Coutinho ◽  
Eduardo Pondé de Sena
Keyword(s):  
Clinical Trials ◽  
Atypical Antipsychotic ◽  
Atypical Antipsychotics ◽  
Rating Scale ◽  
Study Drug ◽  
Typical Antipsychotic ◽  
The Difference ◽  
Psychiatric Rating Scale ◽  
Efficacy Parameters ◽  
Typical Antipsychotics

OBJECTIVE: To review the efficacy of placebo in comparison with atypical and typical antipsychotics for the treatment of schizophrenia and schizoaffective disorder and to evaluate the pertinence of using placebo in clinical trials with antipsychotics. METHOD: Trials in which the atypical antipsychotics were compared with typical antipsychotics and placebo were included. A search was conducted using the terms "amisulpride", "aripiprazole", "clozapine", "olanzapine", "quetiapine", "risperidone", "sertindole", "ziprasidone" and "zotepine". Main efficacy parameters were calculated using the proportion of "events" (defined as a deterioration or lack of improvement by at least 20% in Positive and Negative Syndrome Scale or Brief Psychiatric Rating Scale) and the pooled relative risk with random effects, with their respective 95% confidence intervals. We also calculated the necessary sample sizes in studies in which the study drug is compared to a typical antipsychotic or placebo. RESULTS: The pooled efficacy rates observed were 40.8%, 34.9% and 21.3% for the atypical antipsychotics, typical antipsychotics and placebo, respectively. One hundred and sixty six patients would have to be included when a new drug is compared with placebo if calculation is based on a difference of 20% found between the atypical antipsychotic and placebo and 2,054 if the difference sought were that found between the atypical antipsychotic and the typical antipsychotic, i.e. 6%. The estimated therapeutic failures would be 115 of the 166 patients when the study drug is compared with placebo, and 1,274 failures in the 2,054 patients when the study drug is compared to the typical antipsychotic. CONCLUSIONS: Placebo controlled studies may reduce the number of individuals exposed to the harmful effects of ineffective drugs.

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