Estimating the development of landrace and improved maize cultivars as a function of air temperature/Estimativa do desenvolvimento de cultivares crioulas e melhoradas de milho em funcao da temperatura do ar
The objective of this study was to determine the maximum development rates for the phases of emergence, vegetative and reproductive, and to test the performance of the Wang and Engel (WE) model for simulating the development of landrace and improved maize cultivars sown on different dates. Model cal...
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Published in | Ciência rural p. 1737 |
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Main Authors | , , , , , , , , |
Format | Journal Article |
Language | Spanish |
Published |
Universidade Federal de Santa Maria
01.10.2016
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Subjects | |
Online Access | Get full text |
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Summary: | The objective of this study was to determine the maximum development rates for the phases of emergence, vegetative and reproductive, and to test the performance of the Wang and Engel (WE) model for simulating the development of landrace and improved maize cultivars sown on different dates. Model calibration was with data collected from a field experiment with a sowing date on December 13, 2014, and the model was tested with independent data from experiments with five sowing dates (August 20 and November 4, 2013, February 3 and August 15, 2014, and January 7, 2015) in Santa Maria, RS. The experiment was a complete randomized block design with four replicates. The dates of emergence (EM), silking (R1), and physiological maturity (R6) of two landraces ('Cinquentinha' and 'Bico de ouro') and two improved maize cultivars ('BRS Planalto' and 'AS 1573PRO') were recorded. Maximum daily developmental rates varied among cultivars from 0.2400 to 0.3411 [d.sup.-1] for the emergence phase, from 0.0213 to 0.0234 [d.sup.-1] for the vegetative phase, and from 0.0254 to 0.0298 [d.sup.-1] for the reproductive phase. The WE model adequately estimated the developmental stages of landraces and improved maize cultivars with a mean error of 3.7 days. The cardinal temperatures used in the WE model were appropriate to estimate the developmental stages of landraces and improved maize cultivars. Key words: Zea mays L., modeling, phenology, developmental stages. O objetivo neste trabalho foi obter as taxas maximas de desenvolvimento para as fases de emergencia, vegetativa e reprodutiva, e testar o desempenho do modelo de Wang e Engel (WE) para estimar o desenvolvimento de cultivares crioulas e melhoradas de milho em diferentes datas de semeadura. A calibracao foi realizada com dados de um experimento de campo semeado em 13/12/2014, e a validacao com dados independentes de experimentos semeados em 20/08/2013, 04/11/2013, 03/02/2014, 15/08/2014 e 07/01/2015 em Santa Maria, RS. O delineamento foi blocos ao acaso com quatro repeticoes. Foram registradas as datas de emergencia (EM), espigamento (R1) e maturidade fisiologica (R6) de duas cultivares crioulas ('Cinquentinha'e 'Bico de ouro') e duas melhoradas ('BRS Planalto' e 'AS 1573PRO'). As taxas maximas de desenvolvimento diario diferiram entre as cultivares variando de 0,2400 a 0,3411 [dia.sup.-1] para a fase de emergencia, de 0,0213 a 0,0234 [dia.sup.-1] para a fase vegetativa e de 0,0254 a 0,0298 [dia.sup.-1] para a fase reprodutiva. O modelo WE estimou adequadamente os estagios de desenvolvimento de cultivares crioulas e melhoradas de milho, com um erro medio de 3,7 dias. As temperaturas cardinais utilizadas no modelo WE sao apropriadas para estimar os estagios de desenvolvimento de cultivares crioulas e melhoradas de milho. Palavras-chave: Zea mays L., modelagem, fenologia, estagios de desenvolvimento. |
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ISSN: | 0103-8478 1678-4596 |
DOI: | 10.1590/0103-8478cr20151236 |