Compositional nutrient diagnosis of corn using the Mahalanobis distance as nutrient imbalance index

Registro completo de metadados
MetadadosDescriçãoIdioma
Autor(es): dc.contributorUniversité Laval-
Autor(es): dc.contributorUniversidade Estadual Paulista (UNESP)-
Autor(es): dc.contributor2560 Hochelaga Blvd.-
Autor(es): dc.creatorParent, Léon Etienne-
Autor(es): dc.creatorNatale, William-
Autor(es): dc.creatorZiadi, Noura-
Data de aceite: dc.date.accessioned2025-08-21T17:23:48Z-
Data de disponibilização: dc.date.available2025-08-21T17:23:48Z-
Data de envio: dc.date.issued2022-04-29-
Data de envio: dc.date.issued2022-04-29-
Data de envio: dc.date.issued2009-08-01-
Fonte completa do material: dc.identifierhttp://dx.doi.org/10.4141/cjss08050-
Fonte completa do material: dc.identifierhttp://hdl.handle.net/11449/231886-
Fonte: dc.identifier.urihttp://educapes.capes.gov.br/handle/11449/231886-
Descrição: dc.descriptionCompositional nutrient diagnosis (CND) provides a plant nutrient imbalance index (CND - r2) with assumed χ2 distribution. The Mahalanobis distance D2, which detects outliers in compositional data sets, also has a χ2 distribution. The objective of this paper was to compare D2 and CND - r2 nutrient imbalance indexes in corn (Zea mays L.). We measured grain yield as well as N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn concentrations in the ear leaf at silk stage for 210 calibration sites in the St. Lawrence Lowlands [2300-2700 corn thermal units (CTU)] as well as 30 phosphorus (2300-2700 CTU; 10 sites) and 10 nitrogen (1900-2100 CTU; one site) replicated fertilizer treatments for validation. We derived CND norms as mean, standard deviation, and the inverse covariance matrix of centred log ratios (clr) for high yielding specimens (≥9.0 Mg grain ha-1 at 150 g H2O kg-1 moisture content) in the 2300-2700 CTU zone. Using χ2 = 17 (P <0.05) with nine degrees of freedom (i.e., nine nutrients) as a rejection criterion for outliers and a yield threshold of 8.6 Mg ha-1 after Cate-Nelson partitioning between low- and high-yielders in the P validation data set, D2 misclassified two specimens compared with nine for CND -r2. The D2 classification was not significantly different from a χ2 classification (P >0.05), but the CND - r2 classification differed significantly from χ2 or D2(P <0.001). A threshold value for nutrient imbalance could thus be derived probabilistically for conducting D2 diagnosis, while the CND - r2 nutrient imbalance threshold must be calibrated using fertilizer trials. In the proposed CND -D2 procedure, D2 is first computed to classify the specimen as possible outlier. Thereafter, nutrient indices are ranked in their order of limitation. The D2 norms appeared less effective in the 1900-2100 CTU zone.-
Descrição: dc.descriptionDepartment of Soils and Agrifood Engineering Paul Comtois Bldg. Université Laval, QC G1K 7P4-
Descrição: dc.descriptionDepartment of Soils and Fertilizers Unesp São Paulo State University-
Descrição: dc.descriptionAgriculture and Agri-Food Canada Soils and Crops Research and Development Centre 2560 Hochelaga Blvd., Quebec, QC G1V 2J3-
Descrição: dc.descriptionDepartment of Soils and Fertilizers Unesp São Paulo State University-
Formato: dc.format383-390-
Idioma: dc.languageen-
Relação: dc.relationCanadian Journal of Soil Science-
???dc.source???: dc.sourceScopus-
Palavras-chave: dc.subjectχ2 distribution-
Palavras-chave: dc.subjectGrain corn-
Palavras-chave: dc.subjectNitrogen and phosphorus fertilization-
Palavras-chave: dc.subjectNutrient balance-
Palavras-chave: dc.subjectSimplex closure-
Palavras-chave: dc.subjectVariance-covariance matrix-
Título: dc.titleCompositional nutrient diagnosis of corn using the Mahalanobis distance as nutrient imbalance index-
Tipo de arquivo: dc.typelivro digital-
Aparece nas coleções:Repositório Institucional - Unesp

Não existem arquivos associados a este item.