Maize yield response to a phosphorus-solubilizing microbial inoculant in field trials

SUMMARYFindings from multi-year, multi-site field trial experiments measuring maize yield response to inoculation with the phosphorus-solubilizing fungus,Penicillium bilaiaeChalabuda are presented. The main objective was to evaluate representative data on crop response to the inoculant across a broad set of different soil, agronomic management and climate conditions. A statistical analysis of crop yield response and its variability was conducted to guide further implementation of a stratified trial and sampling plan. Field trials, analysed in the present study, were conducted across the major maize producing agricultural cropland of the United States (2005–11) comprising 92 small (with sampling replication) and 369 large (without replication) trials. The multi-plot design enabled both a determination of how sampling area affects the estimation of maize yield and yield variance and an estimation of the ability of inoculation withP. bilaiaeto increase maize yield. Inoculation increased maize yield in 66 of the 92 small and 295 of the 369 large field trials (within the small plots, yield increased significantly at the 95% confidence level, by 0·17 ± 0·044 t/ha or 1·8%, while in the larger plots, yield increases were higher and less variable (i.e., 0·33 ± 0·026 t/ha or 3·5%). There was considerable inter-annual variability in maize yield response attributed to inoculation compared to the un-inoculated control, with yield increases varying from 0·7 ± 0·75 up to 3·7 ± 0·73%. No significant correlation between yield response and soil acidity (i.e., pH) was detected, and it appears that pH reduction (through organic acid or proton efflux) was unlikely to be the primary pathway for better phosphorus availability measured as increased yield. Seed treatment and granular or dribble band formulations of the inoculant were found to be equally effective. Inoculation was most effective at increasing maize yield in fields that had low or very low soil phosphorus status for both small and large plots. At higher levels of soil phosphorus, yield in the large plots increased more with inoculation than in the small plots, which could be explained by phosphorus fertilization histories for the different field locations, as well as transient (e.g., rainfall) and topographic effects.

Download Full-text

Meta-analysis of soybean yield response to foliar fungicides evaluated from 2005 to 2018 in the United States and Canada

Plant Disease ◽

10.1094/pdis-07-20-1578-re ◽

2020 ◽

Author(s):

Yuba Raj Kandel ◽

Catherine L. Hunt ◽

Keith A Ames ◽

Nicholas Arneson ◽

Carl Bradley ◽

...

Keyword(s):

Meta Analysis ◽

Random Effect ◽

The United States ◽

Field Trials ◽

Yield Response ◽

Application Date ◽

Economic Analyses ◽

Meta Analyses ◽

Yield Responses ◽

Spray Control

Random-effect meta-analyses were performed on data from 240 field trials conducted between 2005 and 2018 across nine U.S. states and Ontario, Canada, to quantify the yield response of soybean after application of foliar fungicides at beginning pod (R3). Meta-analysis showed that the overall mean yield response when fungicide was used compared to not applying a fungicide was 2.7% (110 kg/ha). Moderator variables were also investigated and included fungicide group, growing season, planting date, and base yield, which all significantly influenced the yield response. There was also evidence that precipitation from the time of planting to the R3 growth stage influenced yield when fungicide was used (P = 0.059). Fungicides containing a premix of active ingredients from multiple groups (either two or three ingredients) increased the yield by 3.0% over not applying a fungicide. The highest and lowest yield responses were observed in 2005 and 2007, respectively. Better yield response to fungicides (a 3.0% increase) occurred when soybeans were planted not later than 21 May and when total precipitation between planting and the R3 application date was above historic averages. Temperatures during the season did not influence the yield response . Yield response to fungicide was higher (a 4.7% increase) in average yield category (no spray control yield 2878 to 3758 kg/ha) and then gradually decreased with increasing base yield. Partial economic analyses indicated that use of foliar fungicides is less likely to be profitable when foliar diseases are absent or at low levels.

Download Full-text

Influence of Open Alleys in Field Trials Assessing Yield Effects from Fungicides in Corn

Plant Disease ◽

10.1094/pdis-04-14-0415-re ◽

2015 ◽

Vol 99 (2) ◽

pp. 263-266 ◽

Cited By ~ 5

Author(s):

Paul Vincelli ◽

Chad Lee

Keyword(s):

Large Scale ◽

Field Testing ◽

The United States ◽

Field Trials ◽

Yield Response ◽

Corn Production ◽

Field Corn ◽

Interplant Competition ◽

Published Research ◽

Assessment Of Treatment Effects

Including open alleys at ends of plots is a common practice when field-testing foliar fungicides used in corn production. Open alleys facilitate movement of workers and equipment between plots during spray application. Open alleys affect crop yield estimates in small plots typically used in replicated, randomized experimental designs, because of reduced interplant competition. However, no published research has tested whether the alley effect interacts with fungicide to bias the assessment of the agronomic effects of the latter. We tested this hypothesis over 2 years by evaluating yield with and without application of Headline AMP (containing pyraclostrobin and metconazole) plus nonionic surfactant applied once at VT/R1 in 7.6-m plots separated on their ends by 1.5-m alleys free of aboveground vegetation. In each plot, data were collected from seven subplots, each measuring 1.09 m of row-length and running parallel to the long axis of the plot. Consistent with previous reports, yields of subplots were substantially higher toward plot ends than in the central areas of plots. Surprisingly, a significant (P < 0.10) fungicide × subplot interaction was observed in both experiments, indicating that the yield response from fungicide depended on subplot position within the plot. However, yield differences due to fungicide were trivial when comparing regression-based yield estimates from all seven subplot positions to those obtained from only the centermost three subplot positions. Our study does not lend support to the hypothesis that the open-alley design creates a meaningful bias in assessment of treatment effects due to foliar fungicides in corn. However, additional research on this question is warranted, given the complexities of comparing results in large-scale plots vs. small plots, the limitations of our study, and the widespread use of fungicides on field corn in the United States.

Download Full-text

Heat-Related Illness in Midwestern Hispanic Farmworkers: A Descriptive Analysis of Hydration Status and Reported Symptoms

Workplace Health & Safety ◽

10.1177/2165079918813380 ◽

2019 ◽

Vol 67 (4) ◽

pp. 168-178

Author(s):

Kennith Culp ◽

Shalome Tonelli

Keyword(s):

Crop Production ◽

The United States ◽

Field Trials ◽

Hydration Status ◽

Breathing Rate ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Climate Conditions ◽

Migrant And Seasonal Farmworkers ◽

Seasonal Farmworkers

Heat-related illness (HRI) is a largely undocumented phenomenon in Midwestern Hispanic migrant and seasonal farmworkers in the United States. Frequently, the physiological burden of crop production is overlooked while workers are in the fields. We completed a mixed-methods study using a cross-sectional survey among migrant and seasonal farmworkers about their experience with HRI symptoms ( N = 148) and conducted an intensive surveillance on a smaller group of workers ( N = 20) in field trials ( N = 57 trials) using a chest-strapped multi-parameter monitoring wearable sensor (MPMWS) that measured skin/body temperature, heart and breathing rate, kilocalories burned per hour, and provided a physiological intensity (PI) score. The field trials were conducted across three classes of climate conditions and three PI score categories. We found that those in the uncomfortable category (PI score > 4.0) had a statistically significant ( F ratio = 16.41, p < .001) higher body temperatures ( M = 100.05°F) than those with a mild PI (range = 0-5) score ⩽ 2.5 ( M = 99.56°F) or moderate PI score > 2.5-4 (99.84°F). We also found that those in the uncomfortable climate condition category had a higher mean heart rate and breathing rate than those working under mild and moderate field trials.

Download Full-text

Modelling the response of Mediterranean maize yields to projected climate change

10.5194/egusphere-egu2020-20609 ◽

2020 ◽

Author(s):

Simona Bassu ◽

Davide Fumagalli ◽

Andrea Toreti ◽

Andrej Ceglar ◽

Francesco Giunta ◽

...

Keyword(s):

Climate Change ◽

Climate Model ◽

Crop Yields ◽

Regional Climate ◽

Maize Yield ◽

Climatic Conditions ◽

Future Climate ◽

Yield Response ◽

Climate Conditions ◽

Sowing Dates

<p>Understanding the effects of different combinations of sowing dates and choice of cultivars on maize yield is essential to develop appropriate climate change adaptation strategies. In this study, we explore the maize yield response of two models to changes in sowing dates and cultivars. In particular, we assess whether crop conditions around flowering can explain the variability of irrigated, potential crop yields across sowing dates and cultivars in Mediterranean climatic conditions where high temperatures may change the length of the grain filling period. Then, we investigate these responses under future climate projected conditions till 2060 by using Euro-CORDEX regional climate model simulations.</p><p>Main findings show that the approach based on anthesis conditions outperforms the model based on partitioning. This holds both under current and future climate conditions. Finally, both approaches agree on a warmer climate translating into lower yields (13-18%, average reduction with respect to the current climate conditions) than can only be partially offset by changes in phenology and sowing dates.</p>

Download Full-text

Effects of Mowing, Seeding Rate, and Foliar Fungicide on Soybean Sclerotinia Stem Rot and Yield

Plant Health Progress ◽

10.1094/php-11-20-0097-rs ◽

2021 ◽

Author(s):

Kurt A. Carpenter ◽

Adam J. Sisson ◽

Yuba R. Kandel ◽

Viviana Ortiz ◽

Martin I. Chilvers ◽

...

Keyword(s):

Management Practices ◽

Management Practice ◽

The United States ◽

Field Trials ◽

Cultural Practice ◽

Stem Rot ◽

Yield Response ◽

Sclerotinia Stem Rot ◽

Seeding Rate ◽

Potential Yield

Sclerotinia stem rot (SSR or white mold), caused by Sclerotinia sclerotiorum (Lib.) DeBary, is an economically important fungal disease of soybean. SSR routinely causes yield loss in the upper Corn Belt of the United States due to wet, humid conditions that coincide with moderate temperatures. This study investigated the novel cultural practice of mechanical cutting, or mowing, as an SSR management practice across multiple seeding rates. Mowing soybean during early vegetative growth alters plant architecture and growth habit. This results in a microclimate within the canopy less suitable for disease development. Field trials were conducted in Iowa, Illinois, Michigan, and Wisconsin in 2017 and 2018. Experimental design was a randomized complete block with four replications. Treatments included mowing (mowing and no mowing), seeding rate (197,684, 271,816, and 345,947 seeds/ha), and fungicide application (boscalid, Endura, and no fungicide). Soybean was mowed at approximately the V4 (four unfolded trifoliate leaves) growth stage. Mowing reduced disease in multiple locations; however, it also reduced yield in most of the locations. In general, there was less SSR in plots with lower seeding rates. Fungicide significantly reduced SSR in two of the five site-years for which disease was observed. Significant yield response to fungicide was also observed in two of the nine total field trials. Results indicate cultural practices such as mowing and reduced seeding rate can decrease SSR severity but also can impact potential yield. Additionally, yield response to SSR management practices may not be observed if disease is absent or at low levels.

Download Full-text

Maize Yield Response to Chemical Control of Spodoptera frugiperda at Different Plant Growth Stages in South Africa

Agriculture ◽

10.3390/agriculture11090826 ◽

2021 ◽

Vol 11 (9) ◽

pp. 826

Author(s):

Johnnie van den Berg ◽

Carmen Britz ◽

Hannalene du Plessis

Keyword(s):

Plant Growth ◽

Spodoptera Frugiperda ◽

Yield Loss ◽

Fall Armyworm ◽

Maize Yield ◽

Field Trials ◽

Yield Response ◽

Growth Stages ◽

Yield Losses ◽

Plant Growth Stages

Fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), is a major pest of maize. Yield losses between 30 and 70% in the Americas and between 11 and 100% in Africa have been reported. Little information exists on the effect of pest damage during different plant growth stages on yield loss. Previous studies showed that insecticide applications at weekly intervals did not always provide a yield gain comparable to only a single or two well-timed applications. In this study, we completed four field trials under high natural pest pressure. Treatments consisted of different regimes of insecticide applications that provided protection against damage during different growth stages. In one trial, the mean incidence of infested plants was 65%, and the yield benefit gained from four insecticide applications was 32.6%. The other three trials had 16 treatments which were divided into two spray sequences to protect plants against FAW damage for different lengths of time, between early vegetative stages and tasseling. Yield losses were 41.9, 26.5 and 56.8% for the three respective trials if no insecticides were applied. Yield loss of plants protected during earlier growth stages was significantly lower than that of the treatments which provided protection during later growth stages. More than three spray applications generally completed did not provide further yield gains. Plants that were protected more during early growth stages yield higher than plants protected during later growths stages.

Download Full-text

Responses of soybean genotypes to intercropping with maize in the Southern Guinea Savanna, Nigeria

Acta Agronomica Hungarica ◽

10.1556/aagr.52.2004.2.6 ◽

2004 ◽

Vol 52 (2) ◽

pp. 157-163

Author(s):

C. U. Egbo ◽

M. A. Adagba ◽

D. K. Adedzwa

Keyword(s):

Seed Yield ◽

Block Design ◽

Field Trials ◽

Yield Response ◽

Ecological Zone ◽

Land Equivalent Ratio ◽

Guinea Savanna ◽

Days To Maturity ◽

Soybean Genotypes ◽

Location Interaction

Field trials were conducted in the wet seasons of 1997 and 1998 at Makurdi, Otukpo and Yandev in the Southern Guinea Savanna ecological zone of Nigeria to study the responses of ten soybean genotypes to intercropping. The experiment was laid out in a randomised complete block design. The genotypes TGX 1807-19F, NCRI-Soy2, Cameroon Late and TGX 1485-1D had the highest grain yield. All the Land Equivalent Ratio (LER) values were higher than unity, indicating that there is great advantage in intercropping maize with soybean. The yield of soybean was positively correlated with the days to 50% flowering, days to maturity, plant height, pods/plant and leaf area, indicating that an improvement in any of these traits will be reflected in an increase in seed yield. There was a significant genotype × yield × location interaction for all traits. This suggests that none of these factors acted independently. Similarly, the genotype × location interaction was more important than the genotype × year interaction for seed yield, indicating that the yield response of the ten soybean genotypes varied across locations rather than across years. Therefore, using more testing sites for evaluation may be more important than the number of years.

Download Full-text