scholarly journals Optimal Split-Plot Designs

2002 ◽  
pp. 201-216
Author(s):  
Peter Goos
Keyword(s):  
Split Plot

Power of Modified Brown-Forsythe and Mixed-Model Approaches in Split-Plot Designs

Methodology ◽  
2017 ◽  
Vol 13 (1) ◽  
pp. 9-22 ◽  
Author(s):  
Pablo Livacic-Rojas ◽  
Guillermo Vallejo ◽  
Paula Fernández ◽  
Ellián Tuero-Herrero
Keyword(s):  
Repeated Measures ◽  
Statistical Power ◽  
Mixed Model ◽  
Covariance Structure ◽  
Simulation Method ◽  
Future Research ◽  
Repeated Measures Design ◽  
Fixed And Random Effects ◽  
Split Plot ◽  
High Level

Abstract. Low precision of the inferences of data analyzed with univariate or multivariate models of the Analysis of Variance (ANOVA) in repeated-measures design is associated to the absence of normality distribution of data, nonspherical covariance structures and free variation of the variance and covariance, the lack of knowledge of the error structure underlying the data, and the wrong choice of covariance structure from different selectors. In this study, levels of statistical power presented the Modified Brown Forsythe (MBF) and two procedures with the Mixed-Model Approaches (the Akaike’s Criterion, the Correctly Identified Model [CIM]) are compared. The data were analyzed using Monte Carlo simulation method with the statistical package SAS 9.2, a split-plot design, and considering six manipulated variables. The results show that the procedures exhibit high statistical power levels for within and interactional effects, and moderate and low levels for the between-groups effects under the different conditions analyzed. For the latter, only the Modified Brown Forsythe shows high level of power mainly for groups with 30 cases and Unstructured (UN) and Autoregressive Heterogeneity (ARH) matrices. For this reason, we recommend using this procedure since it exhibits higher levels of power for all effects and does not require a matrix type that underlies the structure of the data. Future research needs to be done in order to compare the power with corrected selectors using single-level and multilevel designs for fixed and random effects.

P—Zn kölcsönhatás mészlepedékes csernozjom talajon kukorica monokultúrában

2002 ◽  
Vol 51 (3-4) ◽  
pp. 381-394 ◽  
Author(s):  
Imre Kádár ◽  
Tamás Turán
Keyword(s):  
List Type ◽  
Split Plot

Szabadföldi P—Zn műtrágyázási tartamkísérletünket 1978 őszén állítottuk be löszön képződött, mély humuszrétegű, vályog mechanikai összetételű karbonátos csernozjom talajon, Intézetünk nagyhörcsöki kísérleti telepén. A talaj szántott rétege 5 % CaCO3-ot, 3 % humuszt tartalmaz; Ca, Mg, Mn és Cu elemekkel kielégítően, N és K elemekkel közepesen, P és Zn elemekkel gyengén ellátott. A talajvíz 13–15 m mélyen helyezkedik el, a termőhely aszályra hajló, vízmérlege negatív. A 4P × 3Zn = 12 kezelést 3 ismétlésben, split-plot elrendezésben állítottuk be. A parcellák mérete 4,9x15=73,5 m². Főparcellaként a 0, 100 kg/ha/év, 500 kg/ha/5 év, 1000 kg/ha/5 év P2O5-trágyázás, alparcellaként a 0, 20, 40 kg/ha/5 év Zn-trágyázás szolgált szuperfoszfát és ZnSO4 formájában. Alaptrágyaként az egész kísérletben egységesen 200 kg/ha N-és 200 kg/ha K2O-műtrágyát alkalmaztunk NH4NO3 és KCl formájában. A termesztett kukoricahibrid az Mv-SC 580 volt. Az első 4 év eredményei alapján levonható főbb következtetések: Kísérleti körülményeink között, ezen a foszforral gyengén ellátott talajon, az évenként adott 100 kg/ha P2O5-trágyázás kielégítheti a kukorica P-igényét. Előretrágyázás formájában ez a mennyiségű foszfor 4–5 évre számolva egyszerre is kiadható. Az 1000 kg/ha feltöltő P2O5-trágyázás gazdaságtalan és Znhiányt indukálva terméscsökkenéshez vezethet. Az AL-oldható P2O5-tartalom optimumát a 100–150 mg/kg érték jelezheti a szántott rétegben.Az egyoldalú, 1000 kg P2O5/ha adaggal előidézett P-túlsúlyt és szemterméscsökkenést a 40 kg/ha Zn-trágyázással lehetett ellensúlyozni. A KCl+EDTA módszerrel meghatározott Zn-tartalom optimumát 2–3 mg/kg talajbani koncentráció mutatta.Irodalmi adagokkal összhangban a kukorica kiegyensúlyozott tápláltsági állapotát a 4–6 leveles légszáraz hajtásban mért 0,3–0,5 % P és 30–60 mg/kg Zn, míg a címerhányáskori levél optimális összetételét 0,25–0,40 % P és 25 mg/kg feletti Zn-koncentráció-tartomány jellemezheti. A P/Zn arányának ideális értéke a vegetatív növényi részekben 50–150 közöttire tehető. Amennyiben ez a P/Zn arány jelentősen 200 fölé emelkedik, a Zn-trágyázás hatékony lehet.A P-túlsúly növelte a meddő tövek előfordulását 1978-ban, amikor szemtelítődés idején (augusztusban) aszály uralkodott. Ebben az évben a termő tövek 13–20 %-a bizonyult terméketlennek.

NGHIÊN CỨU ẢNH HƯỞNG CỦA LƯỢNG GIỐNG GIEO ĐẾN NĂNG SUẤT MỘT SỐ GIỐNG LÚA CHẤT LƯỢNG TRONG ĐIỀU KIỆN THÂM CANH LÚA CẢI TIẾN (SRI) TẠI TỈNH QUẢNG BÌNH

2016 ◽  
Vol 119 (5) ◽  
Author(s):  
Dương Thanh Ngọc ◽  
Hoàng Thị Thái Hòa ◽  
Nguyễn Thị Hải Bình ◽  
Nguyễn Xuân Thủy
Keyword(s):  
Split Plot ◽  
Quang Ninh

Thí nghiệm gồm 4 lượng giống gieo (20, 40, 60 và 80 kg/ha) trên hai giống lúa HT1 và P6, bố trí theo kiểu ô lớn - ô nhỏ (split – plot) với 3 lần nhắc lại, được thực hiện trong vụ Đông Xuân và Hè Thu 2014 trên đất chuyên trồng lúa của huyện Quảng Ninh, tỉnh Quảng Bình nhằm đánh giá ảnh hưởng của lượng giống gieo theo hướng SRI đến một số chi tiêu sinh trưởng, phát triển, năng suất lúa và hiệu quả kinh tế trong sản xuất lúa. Kết quả nghiên cứu cho thấy lượng giống gieo khác nhau có ảnh hưởng đến sinh trưởng, phát triển và năng suất, hiệu quả kinh tế của hai giống lúa nghiên cứu. Nhìn chung lượng giống gieo 60 kg/ha ở vụ đông xuân và 40 - 60 kg/ha ở vụ hè thu có một số chỉ tiêu sinh trưởng tốt, cho năng suất và hiệu quả kinh tế cao nhất, tiếp đến là lượng giống gieo 80 kg/ha ở vụ hè thu và vụ đông xuân.

Induksi Akar dan Tunas Setek Batang Tanaman Pohpohan (Pilea trinervia Wight) dalam Media Air dengan Perlakuan IBA dan Aerasi

2018 ◽  
Vol 6 (3) ◽  
pp. 362
Author(s):  
Katerin Ninariyani ◽  
Darda Efendi ◽  
E. Gunawan
Keyword(s):  
Split Plot

Penelitian ini bertujuan untuk mempelajari pengaruh penggunaan aerasi dan hormon pertumbuhan tanaman Indol -3-butiryc acid (IBA) pada induksi tunas dan akar setek Pohpohan (<em>Pilea trinervia </em>Wight.) dalam media air. Penelitian dilaksanakan di Rumah Kaca Kebun Percobaan Pasir<strong> </strong>Kuda, Pusat Kajian Holtikultura Tropika (PKHT) IPB pada bulan Juni-Oktober 2016. Penelitian menggunakan rancangan split-plot dua faktor dengan empat ulangan. Faktor pertama sebagai petak<strong> </strong>utama adalah aerasi terdiri dari dua taraf yaitu aerasi dan tanpa aerasi. Faktor kedua sebagai anak petak adalah IBA dengan empat taraf konsentrasi yaitu 0.0, 0.5, 1.0, dan 2.0 mg L-1. Hasil penelitian menunjukan bahwa perlakuan aerasi dan IBA berpengaruh terhadap persentase setek bertunas, jumlah akar, panjang akar, jumlah tunas, dan panjang tunas, namun tidak berpengaruh pada persentase setek hidup dan setek berakar. Kombinasi perlakuan tanpa aerasi dan IBA 0.5, 1.0, dan 2.0 mgL-1 menghasilkan jumlah akar paling banyak.

Respon Pertumbuhan dan Produksi Kacang Tanah (Arachis hypogaea L.) terhadap Sistem Tanam Alur dan Pemberian Jenis Pupuk

2017 ◽  
Vol 5 (3) ◽  
pp. 342
Author(s):  
Rizal Mahdi Kurniawan ◽  
Heni Purnamawati ◽  
Yudiwanti Wahyu E. K
Keyword(s):  
Arachis Hypogaea ◽  
Arachis Hypogaea L ◽  
Split Plot ◽  
Plot Design

<p><em>Penelitian ini bertujuan untuk mempelajari pengaruh sistem tanam alur dan pemberian jenis pupuk terhadap pertumbuhan dan produksi kacang tanah (Arachis hypogaea L.). Penelitian dilaksanakan di KP Leuwikopo IPB Dramaga, Bogor pada bulan Februari - Juni 2013. Percobaan menggunakan rancangan petak terbagi (Split Plot Design) dengan perlakuan terdiri dari dua faktor, yaitu sistem tanam alur sebagai petak utama dan jenis pupuk sebagai anak petak. Hasil penelitian menunjukkan bahwa perlakuan sistem tanam alur meningkatkan daya hasil pada produktivitas biji kering, produktivitas polong kering, dan bobot kering biji per tanaman lebih baik dibandingkan sistem tanam konvensional. Hal tersebut ditunjukkan dengan perlakuan sistem tanam alur yang memiliki produktivitas 2.93 ton/ha polong kering, sedangkan sistem tanam konvensional sebesar 2.55 ton/ha polong kering. Sistem budidaya kacang tanah pada sistem tanam alur dapat meningkatkan efisiensi tanaman dalam memanfaatkan unsur hara yang telah diberikan baik pupuk organik maupun anorganik, sehingga pertumbuhan dan hasil tanaman kacang tanah menjadi lebih baik. Pemberian jenis pupuk kandang ayam + Dolomit + NPK memberikan respon terhadap pertumbuhan dan  daya hasil rata-rata tanaman yang lebih baik dibandingkan jenis pupuk lainnya.</em></p>

scholarly journals Interaction of dicamba, fluthiacet-methyl, and glyphosate for control of velvetleaf (Abutilon theopharsti) in dicamba/glyphosate-resistant soybean

2021 ◽  
pp. 1-21
Author(s):  
Jose H. S. de Sanctis ◽  
Amit J. Jhala
Keyword(s):  
United States ◽  
Field Experiments ◽  
The United States ◽  
Application Rate ◽  
Herbicide Application ◽  
Soybean Yield ◽  
Agronomic Crops ◽  
Split Plot ◽  
Main Plot ◽  
Biomass Reduction

Abstract Velvetleaf is an economically important weed in agronomic crops in Nebraska and the United States. Dicamba applied alone usually does not provide complete velvetleaf control, particularly when velvetleaf is greater than 15 cm tall. The objectives of this experiment were to evaluate the interaction of dicamba, fluthiacet-methyl, and glyphosate applied alone or in a mixture in two- or three-way combinations for velvetleaf control in dicamba/glyphosate-resistant (DGR) soybean and to evaluate whether velvetleaf height (≤ 12 cm or ≤ 20 cm) at the time of herbicide application influences herbicide efficacy, velvetleaf density, biomass, and soybean yield. Field experiments were conducted near Clay Center, Nebraska in 2019 and 2020. The experiment was arranged in a split-plot with velvetleaf height (≤ 12 cm or ≤ 20 cm) as the main plot treatment and herbicides as sub-plot treatment. Fluthiacet provided ≥ 94% velvetleaf control 28 d after treatment (DAT) and ≥ 96% biomass reduction regardless of application rate or velvetleaf height. Velvetleaf control was 31% to 74% at 28 DAT when dicamba or glyphosate was applied alone to velvetleaf ≤ 20 cm tall compared with 47% to 100% control applied to ≤ 12 cm tall plants. Dicamba applied alone to ≤ 20 cm tall velvetleaf provided < 75% control and < 87% biomass reduction 28 DAT compared with ≥ 90% control with dicamba at 560 g ae ha−1 + fluthiacet at 7.2 g ai ha−1 or glyphosate at 1,260 g ae ha−1. Dicmaba at 280 g ae ha−1 + glyphosate at 630 g ae ha−1 applied to ≤ 20 cm tall velvetleaf resulted in 86% control 28 DAT compared with the expected 99% control. The interaction of dicamba + fluthiacet + glyphosate was additive for velvetleaf control and biomass reduction regardless of application rate and velvetleaf height.

scholarly journals Corn Nitrogen Status Diagnosis with an Innovative Multi-Parameter Crop Circle Phenom Sensing System

2021 ◽  
Vol 13 (3) ◽  
pp. 401
Author(s):  
Cadan Cummings ◽  
Yuxin Miao ◽  
Gabriel Dias Paiao ◽  
Shujiang Kang ◽  
Fabián G. Fernández
Keyword(s):  
Machine Learning ◽  
Chlorophyll Content ◽  
Vegetation Index ◽  
Soil Drainage ◽  
Management Information ◽  
Area Index ◽  
Sensing System ◽  
Extreme Gradient Boosting ◽  
Split Plot ◽  
N Status

Accurate and non-destructive in-season crop nitrogen (N) status diagnosis is important for the success of precision N management (PNM). Several active canopy sensors (ACS) with two or three spectral wavebands have been used for this purpose. The Crop Circle Phenom sensor is a new integrated multi-parameter proximal ACS system for in-field plant phenomics with the capability to measure reflectance, structural, and climatic attributes. The objective of this study was to evaluate this multi-parameter Crop Circle Phenom sensing system for in-season diagnosis of corn (Zea mays L.) N status across different soil drainage and tillage systems under variable N supply conditions. The four plant metrics used to approximate in-season N status consist of aboveground biomass (AGB), plant N concentration (PNC), plant N uptake (PNU), and N nutrition index (NNI). A field experiment was conducted in Wells, Minnesota during the 2018 and the 2019 growing seasons with a split-split plot design replicated four times with soil drainage (drained and undrained) as main block, tillage (conventional, no-till, and strip-till) as split plot, and pre-plant N (PPN) rate (0 to 225 in 45 kg ha−1 increment) as the split-split plot. Crop Circle Phenom measurements alongside destructive whole plant samples were collected at V8 +/−1 growth stage. Proximal sensor metrics were used to construct regression models to estimate N status indicators using simple regression (SR) and eXtreme Gradient Boosting (XGB) models. The sensor derived indices tested included normalized difference vegetation index (NDVI), normalized difference red edge (NDRE), estimated canopy chlorophyll content (eCCC), estimated leaf area index (eLAI), ratio vegetation index (RVI), canopy chlorophyll content index (CCCI), fractional photosynthetically active radiation (fPAR), and canopy and air temperature difference (ΔTemp). Management practices such as drainage, tillage, and PPN rate were also included to determine the potential improvement in corn N status diagnosis. Three of the four replicated drained and undrained blocks were randomly selected as training data, and the remaining drained and undrained blocks were used as testing data. The results indicated that SR modeling using NDVI would be sufficient for estimating AGB compared to more complex machine learning methods. Conversely, PNC, PNU, and NNI all benefitted from XGB modeling based on multiple inputs. Among different approaches of XGB modeling, combining management information and Crop Circle Phenom measurements together increased model performance for predicting each of the four plant N metrics compared with solely using sensing data. The PPN rate was the most important management metric for all models compared to drainage and tillage information. Combining Crop Circle Phenom sensor parameters and management information is a promising strategy for in-season diagnosis of corn N status. More studies are needed to further evaluate this new integrated sensing system under diverse on-farm conditions and to test other machine learning models.

scholarly journals Performance of hybrid rice grown from separated tillers

2019 ◽  
Vol 17 (4) ◽  
pp. 507-513
Author(s):  
FN Kamarum Munira ◽  
Md. Parvez Anwar ◽  
Sabina Yeasmin ◽  
Md. Harun Or Rashid ◽  
Mst Farzana Rahman ◽  
...  
Keyword(s):  
Grain Yield ◽  
Plant Height ◽  
Hybrid Rice ◽  
Rice Variety ◽  
Field Laboratory ◽  
Split Plot ◽  
Rice Seeds ◽  
Four Levels ◽  
Plot Design

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during July to November 2016 to investigate the performance of separated tillers of hybrid rice variety Dhani Gold. The experiment comprised three times of tiller transplantation viz. 3, 4 and 5 week aged tiller seedlings and four levels of number of tiller seedlings transplanted hill-1 viz. 2, 3, 4 and 5 tiller seedlings hill-1 laid out in a split plot design with 3 replications. The highest plant height was obtained when 3-week aged tiller seedlings were transplanted at the rate of 3 tiller seedlings hill-1. The highest number of total tillers hill-1 and number of effective tillers hill-1 were found when 3-week aged tiller seedlings were transplanted with 5 tiller seedlings hill-1. The highest grains panicle-1 was obtained when 4-week aged tiller seedlings were transplanted with 5 tiller seedlings hill-1. The highest grain yield was found when 3-week aged tiller seedlings were transplanted with 5 tiller seedlings hill-1. The lowest grain yield was found when 5-week aged tiller seedlings were transplanted with 2 tiller seedlings hill-1 in hybrid rice variety Dhani Gold. Based on the findings of the present study it may be concluded that 3-week old tiller seedlings of Dhani Gold should be transplanted at the rate of 4 or 5 tiller seedlings hill-1 for higher yield. Thus present study confirms the potentiality of growing hybrid rice from separated tillers in case of unavailability of seedlings or to minimize the seed cost of high value hybrid rice seeds. J Bangladesh Agril Univ 17(4): 507–513, 2019

Sign in / Sign up

Export Citation Format

Share Document