Is artificial inoculation or natural infection better for evaluating forage maize cultivars for resistance to fumonisin contamination?

SUMMARYThe objectives of the present study were to determine the effects of nitrogen (N) application rate, harvest date and maize cultivar on the yield, quality and the subsequent conservation characteristics of whole-crop, cob and stover silages. The experiment was organized in a spilt-plot design, with harvest date (15 September, 6 October and 27 October) as the main plot, and a three (maize cultivars: Tassilo, Andante and KXA 7211)×two (N application rate: 33 and 168 kg N/ha) factorial arrangement of treatments as the sub-plot, within three replicate blocks, and was conducted at Grange, Dunsany, Co. Meath, Ireland in 2009. The three harvest dates represented early, normal and late harvests, respectively, for a midland site in Ireland. Of the three maize cultivars selected, cvars Tassilo and Andante represent conventional cultivars sown by commercial livestock farmers in Ireland, while cvar KXA 7211 is categorized as a high biomass cultivar. No effect of N application rate was observed on the dry matter (DM) yield, nutritive value or ensiling characteristics of maize whole-crop or cob. Whole-crop and stover harvested on the later date had a lower digestible DM (DDM) content and the silages underwent a more restricted fermentation, compared to silages produced from herbage harvested on earlier dates. Cob silages produced from crops harvested on 15 September had lower DDM content and higher DM loss during ensiling than later harvest dates. Despite higher whole-crop DM yields, the later maturing cultivar KXA 7211 did not improve the DM yields of cob and also resulted in increased DM losses from the ensilage of cob, when compared with the other cultivars. In addition to the DM yield and nutritive value of forage maize at harvest, the subsequent fermentation profile during ensilage influences the optimum choice of cultivar and date for crop harvest in a maize silage production system.

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Response of Barley Genotypes to Fusarium Head Blight under Natural Infection and Artificial Inoculation Conditions

The Plant Pathology Journal ◽

10.5423/ppj.oa.06.2021.0094 ◽

2021 ◽

Vol 37 (5) ◽

pp. 455-464

Author(s):

Raja Khanal ◽

Thin Meiw Choo ◽

Allen G. Xue ◽

Bernard Vigier ◽

Marc E. Savard ◽

...

Keyword(s):

Fusarium Head Blight ◽

Prince Edward Island ◽

Natural Infection ◽

Spring Barley ◽

Artificial Inoculation ◽

High Yield ◽

Conidial Suspension ◽

Head Blight ◽

One Year ◽

Barley Genotypes

Forty-eight spring barley genotypes were evaluated for deoxynivalenol (DON) concentration under natural infection across 5 years at Harrington, Prince Edward Island. These genotypes were also evaluated for Fusarium head blight (FHB) severity and DON concentration under field nurseries with artificial inoculation of Fusarium graminearum by the grain spawn method across 2 years at Ottawa, Ontario, and one year at Hangzhou, China. Additionally, these genotypes were also evaluated for FHB severity under greenhouse conditions with artificial inoculation of F. graminearum by conidial suspension spray method across 3 years at Ottawa, Ontario. The objective of the study was to investigate if reactions of barley genotypes to artificial FHB inoculation correlate with reactions to natural FHB infection. DON concentration under natural infection was positively correlated with DON concentration (r = 0.47, P < 0.01) and FHB incidence (r = 0.56, P < 0.01) in the artificially inoculated nursery with grain spawn method. Therefore, the grain spawn method can be used to effectively screen for low DON. FHB severity, generated from greenhouse spray, however, was not correlated with DON concentration (r = 0.12, P > 0.05) under natural infection and it was not correlated with DON concentration (r = -0.23, P > 0.05) and FHB incidence (r = 0.19, P > 0.05) in the artificially inoculated nursery with grain spawn method. FHB severity, DON concentration, and yield were affected by year, genotype, and the genotype × year interaction. The effectiveness of greenhouse spray inoculation for indirect selection for low DON concentration requires further studies. Nine of the 48 genotypes were found to contain low DON under natural infection. Island barley had low DON and also had high yield.

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Weed-Competitive Ability of Forage Maize Cultivars against Barnyardgrass

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v8i1.174-178.2940 ◽

2020 ◽

Vol 8 (1) ◽

pp. 174

Author(s):

Khawar Jabran

Keyword(s):

Competitive Ability ◽

Research Work ◽

Dry Weight ◽

Leaf Length ◽

Fresh Weight ◽

Forage Maize ◽

Shoot Dry Weight ◽

Maize Cultivars ◽

Maize Plants ◽

Leaf Dry Weight

Weed-competitive cultivars are desired in the wake of growing popularity of organic farming, environmental pollution and evolution of herbicide resistance in weeds. This research work evaluated the weed competitive ability of three forage maize cultivars (ADA-523, AGA and SASA-5) against the noxious weed barnyardgrass (Echinochloa crus-galli (L.) P.Beauv.). The study was conducted in spring 2018 and repeated in summer 2018. Results of this study showed that maize-barnyardgrass competition significantly decreased the growth of forage maize plants. For instance, barnyardgrass decreased the maize plant height by 11.9-16.9%, leaf length by 13.3-20.2%, leaf width by 20.2-27.4%, and number of leaves by 14.3-25.0%. Fresh and dry weights of maize plants were also significantly decreased as a result of weed-crop competition. Barnyardgrass decreased the shoot fresh weight (30.7-60.6%), shoot dry weight (33.3-52.2%), leaf fresh weight (33.4-56.5%) and leaf dry weight (31.9-50.0%) of the maize plants. An interactive effect of weed × maize cultivars was found non-significant. Forage maize cultivars also varied occasionally for their traits. Nevertheless, ADA-523 had a higher plant height, leaf length, leaf width, leaf fresh weight and leaf dry weight than the cultivars AGA and SASA-5. On the other hand, the cultivar SASA-5 had a higher shoot fresh weight, shoot dry weight and root fresh weight than the other cultivars in the study. This research work concluded that the forage maize cultivars in the study did not vary for the weed-competitive ability. Further, barnyardgrass-maize competition could decrease the growth and development of the maize cultivars.

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Correlation between maize genotypes and the stalk rot caused by maize Fusarium

Acta Agronomica Hungarica ◽

10.1556/aagr.55.2007.4.5 ◽

2007 ◽

Vol 55 (4) ◽

pp. 447-452 ◽

Cited By ~ 2

Author(s):

C. Szőke ◽

T. Árendás ◽

F. Rácz ◽

J. Pintér ◽

E. Nagy ◽

...

Keyword(s):

Natural Infection ◽

Female Parent ◽

Weather Conditions ◽

Artificial Inoculation ◽

Resistance Level ◽

Stalk Rot ◽

Maize Genotypes ◽

Female Component ◽

Different Levels ◽

Single Cross Hybrids

Six single-cross hybrids and their parental lines were inoculated with the FG36 Fusarium graminearum isolate in 2005 and 2006. In both years the degree of infection increased after artificial inoculation for both the hybrids and the inbred lines compared with the level of natural infection. The more severe stalk infection recorded in 2005 than in 2006 could be attributed to the weather conditions during flowering and harvesting.The 18 genotypes examined exhibited different levels of resistance to fusarium stalk rot. It could be concluded from the results that the resistance level of the female parent was decisive in the inheritance of the response to fusarium stalk rot (female component-hybrid r = 0.88, male component-hybrid r = 0.39).Some genotypes may be severely affected in epidemic years, while exhibiting a lower rate of infection in years with lower pathogen pressure. This suggests that successful breeding for resistance can only be carried out efficiently by means of artificial inoculation.

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The association of maize characteristics with resistance to Fusarium verticillioides and fumonisin accumulation in commercial maize cultivars

World Mycotoxin Journal ◽

10.3920/wmj2019.2537 ◽

2020 ◽

Vol 13 (3) ◽

pp. 367-379

Author(s):

S. Links ◽

K. van Zyl ◽

A. Cassiem ◽

B.C. Flett ◽

A. Viljoen ◽

...

Keyword(s):

Gene Expression ◽

Natural Infection ◽

Fusarium Verticillioides ◽

Field Trials ◽

Disease Development ◽

Ear Rot ◽

Phenotypic Data ◽

Maize Cultivars ◽

Physico Chemical ◽

Grain Yield And Quality

Fusarium verticillioides is the primary fungus that causes Fusarium ear rot (FER) of maize. Infection results in reduced grain yield and quality due to moulding and the contamination of grain with toxic compounds namely fumonisins. Resistance to fungal infection and fumonisin accumulation in maize and maize grain is governed at different levels. In this study, the structural, physico-chemical and genetic basis of resistance to F. verticillioides was investigated in two, replicated field trials at Potchefstroom and Vaalharts in South Africa. Phenotypic data (silk length, husk coverage, pericarp thickness hundred-kernel mass and kernel hardness), physico-chemical data (kernel pH, moisture content, total nitrogen and carbon as well as phenolic acid content) and the expression of pathogenesis-related-5 gene (PR5) and peroxidase gene expression was evaluated in 15 commercial cultivars under artificially inoculated and natural infection conditions. The data were correlated to FER severity, fumonisin accumulation and fungal DNA (referred to as infection indicators). Disease development and fumonisin contamination in Vaalharts was significantly more than in Potchefstroom. There were no significant correlations (r=≥0.60) between phenotypic characteristics and infection indicators. Kernel pH was the most important trait associated with disease development and was negatively correlated (between r=-0.58 and r=-0.75) to all infection indicators. PR5 gene expression had significant positive correlations (r=0.69 and r=0.72) with the fungal and fumonisin levels, respectively. This study presents of the first data demonstrating the use of gene expression in identifying FER/fumonisin-resistant plant material and could aid breeders and growers in selecting resistant material more effectively.

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Evaluation of Maize Inbred Lines for Resistance to Fusarium Ear Rot and Fumonisin Accumulation in Grain in Tropical Africa

Plant Disease ◽

10.1094/pdis-91-3-0279 ◽

2007 ◽

Vol 91 (3) ◽

pp. 279-286 ◽

Cited By ~ 42

Author(s):

C. G. Afolabi ◽

P. S. Ojiambo ◽

E. J. A. Ekpo ◽

A. Menkir ◽

R. Bandyopadhyay

Keyword(s):

Disease Severity ◽

Natural Infection ◽

Fusarium Verticillioides ◽

Field Trials ◽

Inbred Lines ◽

Artificial Inoculation ◽

Fusarium Ear Rot ◽

Ear Rot ◽

Maize Inbred Lines ◽

Resistant Lines

Fusarium ear rot and fumonisin contamination is a major problem facing maize growers worldwide, and host resistance is the most effective strategy to control the disease, but resistant genotypes have not been identified. In 2003, a total of 103 maize inbred lines were evaluated for Fusarium ear rot caused by Fusarium verticillioides in field trials in Ikenne and Ibadan, Nigeria. Disease was initiated from natural infection in the Ikenne trial and from artificial inoculation in the Ibadan trial. Ear rot severity ranged from 1.0 to 6.0 in both locations in 2003. Fifty-two inbred lines with disease severity ≤3 (i.e., ≤ 10% visible symptoms on ears) were selected and reevaluated in 2004 for ear rot resistance, incidence of discolored kernels, and fumonisin contamination in grain. At both locations, ear rot severity on the selected lines was significantly (P < 0.0020) higher in 2004 than in 2003. The effects of selected inbred lines on disease severity were highly significant at Ikenne (P = 0.0072) and Ibadan (P < 0.0001) in 2004. Inbred lines did not affect incidence of discolored kernels at both locations and across years except at Ikenne (P = 0.0002) in 2004. Similarly, significant effects of inbred lines on fumonisin concentration were observed only at Ikenne (P = 0.0201) in 2004. However, inbred lines 02C14585, 02C14593, 02C14603, 02C14606, 02C14624, and 02C14683 had consistently low disease severity across years and locations. Fumonisin concentration was significantly correlated with ear rot only at Ikenne (R = 0.42, P < 0.0001). Correlation between fumonisin concentration and incidence of discolored kernels was also significant at Ikenne (R = 0.39, P < 0.0001) and Ibadan (R = 0.35, P = 0.0007). At both locations, no significant inbred × year interaction was observed for fumonisin concentration. Five inbred lines, namely 02C14585, 02C14603, 02C14606, 02C14624, and 02C14683, consistently had the lowest fumonisin concentration in both trials. Two of these inbred lines, 02C14624 and 02C14585, had fumonisin levels <5.0 μg/g across years in trials where disease was initiated from both natural infection and artificial inoculation. These lines that had consistently low disease severity are useful for breeding programs to develop fumonisin resistant lines.

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Crop genotype-environment modelling to evaluate forage maize cultivars under climate variability

Acta Agriculturae Scandinavica Section B - Soil & Plant Science ◽

10.1080/09064710.2014.885076 ◽

2014 ◽

Vol 64 (1) ◽

pp. 56-70 ◽

Cited By ~ 1

Author(s):

Libère Nkurunziza ◽

Alois Kornher ◽

Mårten Hetta ◽

Magnus Halling ◽

Martin Weih ◽

...

Keyword(s):

Climate Variability ◽

Forage Maize ◽

Maize Cultivars ◽

Environment Modelling

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Occurrence of Fusarium Mycotoxins and Their Modified Forms in Forage Maize Cultivars

Toxins ◽

10.3390/toxins13020110 ◽

2021 ◽

Vol 13 (2) ◽

pp. 110 ◽

Cited By ~ 1

Author(s):

Tim Birr ◽

Tolke Jensen ◽

Nils Preußke ◽

Frank D. Sönnichsen ◽

Marthe De Boevre ◽

...

Keyword(s):

High Resolution Mass Spectrometry ◽

Fusarium Mycotoxins ◽

Forage Maize ◽

Mycotoxin Contamination ◽

Modified Mycotoxins ◽

Maize Cultivars ◽

Wide Range ◽

Positive Correlations ◽

Almost All ◽

Modified Forms

Forage maize is often infected by mycotoxin-producing Fusarium fungi during plant growth, which represent a serious health risk to exposed animals. Deoxynivalenol (DON) and zearalenone (ZEN) are among the most important Fusarium mycotoxins, but little is known about the occurrence of their modified forms in forage maize. To assess the mycotoxin contamination in Northern Germany, 120 natural contaminated forage maize samples of four cultivars from several locations were analysed by liquid chromatography-high resolution mass spectrometry (LC-HRMS) for DON and ZEN and their modified forms deoxynivalenol-3-glucoside (DON3G), the sum of 3- and 15-acetyl-deoxynivalenol (3+15-AcDON), α- and β-zearalenol (α-ZEL, β-ZEL). DON and ZEN occurred with high incidences (100 and 96%) and a wide range of concentrations, reaching levels up to 10,972 and 3910 µg/kg, respectively. Almost half of the samples (46%) exceeded the guidance value in complementary and complete feeding stuffs for ZEN (500 µg/kg), and 9% for DON (5000 µg/kg). The DON related mycotoxins DON3G and 3+15-AcDON were also present in almost all samples (100 and 97%) with amounts of up to 3038 and 2237 µg/kg and a wide range of concentrations. For the ZEN metabolites α- and β-ZEL lower incidences were detected (59 and 32%) with concentrations of up to 423 and 203 µg/kg, respectively. Forage maize samples were contaminated with at least three co-occurring mycotoxins, whereby 95% of all samples contained four or more mycotoxins with DON, DON3G, 3+15-AcDON, and ZEN co-occurring in 93%, together with α-ZEL in 57% of all samples. Positive correlations were established between concentrations of the co-occurring mycotoxins, especially between DON and its modified forms. Averaged over all samples, ratios of DON3G/DON and 3+15-AcDON/DON were similar, 20.2 and 20.5 mol%; cultivar-specific mean ratios ranged from 14.6 to 24.3 mol% and 15.8 to 24.0 mol%, respectively. In total, 40.7 mol% of the measured DON concentration was present in the modified forms DON3G and 3+15-AcDON. The α-ZEL/ZEN ratio was 6.2 mol%, ranging from 5.2 to 8.6 mol% between cultivars. These results demonstrate that modified mycotoxins contribute substantially to the overall mycotoxin contamination in forage maize. To avoid a considerable underestimation, it is necessary to analyse modified mycotoxins in future mycotoxin monitoring programs together with their parent forms.

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Growth analysis of dry matter accumulation and N uptake of forage maize cultivars affected by N supply

The Journal of Agricultural Science ◽

10.1017/s0021859698006145 ◽

1999 ◽

Vol 132 (1) ◽

pp. 31-43 ◽

Cited By ~ 13

Author(s):

J. M. GREEF ◽

H. OTT ◽

R. WULFES ◽

F. TAUBE

Keyword(s):

Growth Rate ◽

Uptake Rate ◽

Growth Analysis ◽

N Uptake ◽

Crop Growth ◽

Forage Maize ◽

Crop Growth Rate ◽

Maize Cultivars ◽

N Uptake Rate ◽

Grass Sward

The productivity of eight forage maize cultivars (Zea mays L.) in response to N was investigated in a 3-year field experiment located in Northern Germany. Nitrogen fertilizer applications were zero, 50 and 150 kg N/ha given each year shortly after sowing. Each cultivar was grown on the same plot, beginning in 1993, following the ploughing up of a 2-year old grass sward, to which slurry had been added. Plants were sampled regularly for dry matter (DM) production and N uptake. A non-linear regression equation was used to compare the data. Growth analysis and N uptake characteristics (maximum crop growth rate, duration of maximum crop growth rate, period until maximum crop growth rate, maximum N uptake rate, duration of maximum N uptake rate, period until maximum N uptake rate) which derived from the function were used to compare the cultivars.The cultivars DM yield and N uptake were highest in 1993 and declined in the next two years partly due to a decrease in soil N mineralization following the ploughing of the grass sward and partly due to the drier weather conditions during the summers of 1994 and 1995. Duration of the maximum crop growth rate was greater during the cool year of 1993. In contrast, maximum crop growth rate was at its highest in the dry vegetation period of 1995. A significant N×cultivar interaction for growth analysis characteristics (P<0·05) was found in 1995. Cultivars with a high maximum crop growth rate (above the average value of the eight cultivars tested) and a short duration of maximum crop growth rate (below the average) accumulated more DM than those genotypes which showed an inverse relationship.Increasing N yield was determined by increased maximum N uptake rather than by a greater duration of maximum N uptake. A significant N×genotype interaction for N uptake parameters (P<0·05) was found in 1994 and 1995. With some exceptions, cultivars with a high maximum N uptake rate (above average) accumulated more N per unit area compared to those genotypes which had low uptake rates. The exceptions had a longer duration of uptake, which could not, however, compensate for the lower rate. Maximum N uptake rate occurred earlier and duration of maximum N uptake rate increased compared to the start and duration of maximum crop growth rate. Especially in 1995, the amount of N taken up before the day of maximum crop growth rate accounted for 71% of total N uptake. The N uptake rate and the amount of accumulated N until the day of maximum crop growth rate were highly correlated with DM yield.This result indicates the availability of genotypic variability in crop growth and N uptake rate to assist the improvement of DM yield by selection.

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