Sufficient number of experiments for the adaptability and stability analyses of maize using the Eberhart and Russell method

Abstract: The objective of this work was to determine the sufficient number of experiments (environments) for the adaptability and stability analyses of maize cultivars, using the Eberhart and Russell method. Grain yield data from 63 trials of maize cultivars from six groups of experiments were used. In each group, new data files were formed from all experiments (n), for the combinations of 3, 4, ..., n-1 experiments, totaling 10,381 files. Mean and estimates of the adaptability (b) and stability (S2d) parameters were obtained for each cultivar, in each file. A power function was adjusted for the amplitudes of b and S2d (dependent variables) in each cultivar, as a function of the number of experiments (independent variable), totaling 290 equations (145 cultivars × two dependent variables). For each equation, the value was determined on the abscissa axis (Xs, sufficient number of experiments), corresponding to the point of maximum curvature. The highest value among the 290 estimates of Xs, rounded up to the nearest integer, was assumed to be the sufficient number of experiments for the analyses. Seven experiments are sufficient to analyze the adaptability and stability of maize cultivars using the Eberhart and Russell method.

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SUFFICIENT NUMBER OF REPLICATES FOR ESTIMATION OF DISSIMILARITY MEASURES AMONG MAIZE CULTIVARS

Revista Brasileira de Milho e Sorgo ◽

10.18512/rbms2020v19e1181 ◽

2020 ◽

Vol 19 ◽

pp. 14

Author(s):

ALBERTO CARGNELUTTI FILHO ◽

MARCOS TOEBE

Keyword(s):

Power Function ◽

Coefficient Of Variation ◽

Block Design ◽

Dissimilarity Measure ◽

Abscissa Axis ◽

Dissimilarity Measures ◽

Maize Cultivars ◽

Randomized Block Design ◽

Data Files ◽

Independent Variable

The objective of this work was to determine the sufficient number of replicates for estimation of dissimilarity measures among maize cultivars. Data of five variables were used, which were evaluated in an experiment with 15 maize cultivars, in randomized block design with nine replicates. A number of 511 data files were formed, being 9, 36, 84, 126, 126, 84, 36, 9, and 1 obtained, respectively from 1, 2, 3, 4, 5, 6, 7, 8, and 9 replicates. Three dissimilarity matrices were determined between i and i’ cultivars containing, respectively, Euclidean, Manhattan, and Chebyshev distances. For each of the 105 distances between cultivars, in each dissimilarity measure, the power function was adjusted for the coefficient of variation of the (dependent variable) as a function of the number of replicates (independent variable), totaling 315 equations. For each equation, the abscissa axis value (Xs, sufficient number of replicates) was determined, corresponding to the maximum curvature point. With the increase of the number of replicates, there is an improvement in the accuracy of the estimates of dissimilarity measures among maize cultivars, however, the gains in precision decrease gradually. Six replicates are sufficient to estimate the dissimilarity measures among maize cultivars expressed by the Euclidean, Manhattan, and Chebyshev distances.

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Number of experiments for adaptability and stability analysis in maize by Lin and Binns method

Ciência Rural ◽

10.1590/0103-8478cr20170130 ◽

2018 ◽

Vol 48 (3) ◽

Author(s):

Alberto Cargnelutti Filho ◽

José Paulo Guadagnin

Keyword(s):

Zea Mays ◽

Stability Analysis ◽

Grain Yield ◽

Zea Mays L ◽

Spearman Correlation ◽

Yield Data ◽

Maize Cultivars ◽

Reference File ◽

Data Files ◽

Degree Of Association

ABSTRACT: The objective of this study was to determine the necessary number of experiments to analyze the adaptability and stability of maize cultivars (Zea mays L.) using the Lin and Binns method. Grain yield data extracted from 63 maize cultivar trials were used. Trials were divided in six groups of experiments, according to the cycle (early and super early) and the agricultural year (2002/2003, 2003/2004, and 2004/2005). In each group, from the set of all experiments (reference file) new data files were formed by combinations in groups of 2, 3, 4, ..., n-1 experiments, with a total of 10,683 files. For each file, the estimation of the adaptability and stability parameter (Pi) of the Lin and Binns method was calculated. To verify the degree of association of the estimates of Pi obtained with the combinations of experiments and with all the experiments (reference), Spearman correlation coefficient (r) was used. Number of experiments giving values of r≥0.80 in 100% of the combinations was considered sufficient. Seven experiments sufficed for the analysis of adaptability and stability of maize cultivars by the method of Lin and Binns.

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EFFECT OF SOWING DATE ON GRAIN YIELD OF CRAB GRASS

Acta Agronomica Hungarica ◽

10.1556/aagr.49.2001.3.10 ◽

2001 ◽

Vol 49 (3) ◽

pp. 293-297

Author(s):

S. O. Bakare ◽

M. G. M. Kolo ◽

J. A. Oladiran

Keyword(s):

Grain Yield ◽

Interaction Effect ◽

Significant Interaction ◽

Sowing Date ◽

Yield Data ◽

Significant Interaction Effect ◽

Sowing Dates

There was a significant interaction effect between the variety and the sowing date for the number of productive tillers, indicating that the response to sowing date varied with the variety. A significant reduction in the number of productive tillers became evident when sowing was delayed till 26 June in the straggling variety as compared to sowing dates in May. Lower numbers of productive tillers were also recorded when the sowing of the erect variety was further delayed till 10 July. The grain yield data showed that it is not advisable to sow the straggling variety later than 12 June, while sowing may continue till about 26 June for the erect variety in the study area.

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Utilizing Grain Yield Data from Wheat Demonstration Plots

Journal of Agronomic Education ◽

10.2134/jae1990.0164 ◽

1990 ◽

Vol 19 (2) ◽

pp. 164-166 ◽

Cited By ~ 1

Author(s):

Liu Ben-Hui ◽

J. P. Shroyer ◽

T. S. Cox

Keyword(s):

Grain Yield ◽

Yield Data

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Interference of Three Annual Grasses with Grain Sorghum (Sorghum bicolor)

Weed Technology ◽

10.1017/s0890037x00025343 ◽

1990 ◽

Vol 4 (2) ◽

pp. 245-249 ◽

Cited By ~ 19

Author(s):

Brenda S. Smith ◽

Don S. Murray ◽

J. D. Green ◽

Wan M. Wanyahaya ◽

David L. Weeks

Keyword(s):

Linear Regression ◽

Grain Yield ◽

Field Experiments ◽

Grain Sorghum ◽

Grass Species ◽

Row Spacing ◽

Yield Data ◽

Weed Density ◽

Annual Grasses ◽

Wide Row Spacing

Barnyardgrass, large crabgrass, and Texas panicum were evaluated in field experiments over 3 yr to measure their duration of interference and density on grain sorghum yield. When grain yield data were converted to a percentage of the weed-free control, linear regression predicted a 3.6% yield loss for each week of weed interference regardless of year or grass species. Grain sorghum grown in a narrow (61-cm) row spacing was affected little by full-season interference; however, in wide (91-cm) rows, interference increased as grass density increased. Data from the wide-row spacing were described by linear regression following conversion of grain yield to percentages and weed density to log10. A separate nonlinear model also was derived which could predict the effect of weed density on grain sorghum yield.

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Growth and Yield of Wheat under Irrigation by Sugar Mills Wastewater

Progressive Agriculture ◽

10.3329/pa.v24i1-2.19174 ◽

2014 ◽

Vol 24 (1-2) ◽

pp. 211-218

Author(s):

PK Kundu ◽

TK Acharjee ◽

MA Mojid

Keyword(s):

Grain Yield ◽

Fertilizer Application ◽

Wastewater Irrigation ◽

Growth And Yield ◽

Sugar Mill ◽

Yield Data ◽

Full Dose ◽

Sugar Mills ◽

Irrigation Treatments ◽

Mixed Water

The possibility of using sugar mills wastewater/effluent in irrigation was evaluated by investigating the effects of wastewater on growth and yield of wheat (Triticum aestivum cv. Prodip). The experiment was conducted at North Bengal Sugar Mill site in Natore during December 2011 to March 2012. Three irrigation treatments (I1: irrigation with fresh/tubewell water, I2: irrigation with a mixture of fresh and wastewater at 1:1 ratio and I3: irrigation with wastewater) under a main factor and three fertilizer treatments (F0: no application of fertilizer, F1: half dose fertilizer and F2: full dose fertilizer) under a sub factor were evaluated. The experiment was laid out in a split-plot design with three replications of the treatments. Wheat was grown with three irrigations totaling 14 cm applied at 4, 26 and 43 days after sowing (DAS). Important growth and yield data of the crop were recorded. The highest grain yield of 1.829 t/ha was obtained under mixed water irrigation and the lowest grain yield of 1.469 t/ha was obtained under wastewater irrigation. The three irrigation treatments, however, provided statistically similar (p = 0.05) grain yield. For the interaction between irrigation and fertilizers, mixed water irrigation and full dose fertilizer application (I2F2) provided significantly higher grain yield (2.757 t/ha) than all other treatment combinations. The second highest yield, produced under freshwater irrigation and full dose fertilizer (I1F2), was statistically similar to the yield under wastewater irrigation and full dose fertilizer (I3F2). Results of this experiment thus exposed good prospects of irrigating wheat by sugar mills wastewater.DOI: http://dx.doi.org/10.3329/pa.v24i1-2.19174 Progress. Agric. 24(1&2): 211 - 218, 2013

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The gradient nature ofs-lenition in Caleño Spanish

Language Variation and Change ◽

10.1017/s0954394511000056 ◽

2011 ◽

Vol 23 (2) ◽

pp. 223-243 ◽

Cited By ~ 33

Author(s):

Richard J. File-Muriel ◽

Earl K. Brown

Keyword(s):

Symbolic Representation ◽

Speaking Rate ◽

Final Position ◽

Lexical Frequency ◽

Word Position ◽

Dependent Variables ◽

Independent Variable ◽

Linear Regressions

AbstractWhereas previous studies of Spanishs-weakening have relied on impressionistic coding, the present study examines temporal and gradient acoustic details in the production of /s/ by eight females from Cali, Colombia, during sociolinguistic interviews. We propose a metric for quantifyings-realization by employing three scalar-dependent variables:s-duration, centroid, and voicelessness. The results of linear regressions indicate that the dependent variables are significantly conditioned by local speaking rate, word position, following and preceding phonological context, stress, and lexical frequency. This study sheds light on how each independent variable influencess-realization acoustically. For example, as local speaking rate increases, duration, centroid, and voicelessness decrease, which is indicative of lenition, and the same weakening tendency is observed when /s/ occurs in word-final position or is followed by a nonhigh vowel, whereas frequency contributes only tos-duration. We discuss the advantages of opting for instrumental measurements over symbolic representation.

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Seemingly Unrelated Mixed-Effects Biomass Models for Black Locust in West Poland

Forests ◽

10.3390/f12030380 ◽

2021 ◽

Vol 12 (3) ◽

pp. 380

Author(s):

Karol Bronisz ◽

Szymon Bijak ◽

Rafał Wojtan ◽

Robert Tomusiak ◽

Agnieszka Bronisz ◽

...

Keyword(s):

Black Locust ◽

Random Effect ◽

Tree Height ◽

Cross Model ◽

Diameter At Breast Height ◽

Breast Height ◽

Dependent Variables ◽

Dry Biomass ◽

Biomass Components ◽

Independent Variable

Information about tree biomass is important not only in the assessment of wood resources but also in the process of preparing forest management plans, as well as for estimating carbon stocks and their flow in forest ecosystems. The study aimed to develop empirical models for determining the dry mass of the aboveground parts of black locust trees and their components (stem, branches, and leaves). The research was carried out based on data collected in 13 stands (a total of 38 sample trees) of black locust located in western Poland. The model system was developed based on multivariate mixed-effect models using two approaches. In the first approach, biomass components and tree height were defined as dependent variables, while diameter at breast height was used as an independent variable. In the second approach, biomass components and diameter at breast height were dependent variables and tree height was defined as the independent variable. Both approaches enable the fixed-effect and cross-model random-effect prediction of aboveground dry biomass components of black locust. Cross-model random-effect prediction was obtained using additional measurements of two extreme trees, defined as trees characterized by the smallest and largest diameter at breast height in sample plot. This type of prediction is more precise (root mean square error for stem dry biomass for both approaches equals 77.603 and 188.139, respectively) than that of fixed-effects prediction (root mean square error for stem dry biomass for both approaches equals 238.716 and 206.933, respectively). The use of height as an independent variable increases the possibility of the practical application of the proposed solutions using remote data sources.

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