Tamanho de amostra para mosca-branca em soja
Autor(a) principal: | |
---|---|
Data de Publicação: | 2023 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/30795 |
Resumo: | The whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is one of the main pest insects that infest soybean crops. It causes damage through plant sap-sucking, toxin injection, virus transmission, and secretion of a sugar-rich substance that promotes the development of sooty mold. The primary method of controlling the insect is the use of chemical insecticides. Therefore, it is essential to have knowledge of the whitefly population density in the area to determine the need and timing of application. To estimate the population density of the insect pest it is necessary to know the sample size, which is the number of soybean leaflets that should be evaluated. Therefore, the aim of this study was to establish the sample size (number of leaflets) for estimating the mean population density of nymphs and adults of the whitefly in soybean. Twentythree treatments comprising insecticides for whitefly control were evaluated in experiments conducted over two agricultural years, with soybean planting dates on December 11, 2020 (first experiment), and December 17, 2021 (second experiment), with evaluations beginning at the reproductive stages R5.4 and R5.2, respectively. The evaluations were carried out on nine dates in the first experiment and on eight dates in the second experiment. In each experiment, treatment, and date of nymph population assessment, the central leaflet from the middle third of 20 plants per plot (one leaflet per plant) was collected, and the number of nymphs was counted in the laboratory. To assess the adult stage of the whitefly, a visual count was performed in the field on the central leaflet of the upper third of 20 plants per plot (one leaflet per plant). Measures of central tendency and variability were calculated, and normality was verified. The sample size (number of leaflets) was determined based on the Student’s t-distribution. The mean population density of whiteflies was 22.1 nymphs per leaflet and 5.7 adults per leaflet in the first experiment, and 3.0 nymphs per leaflet and 1.9 adults per leaflet in the second experiment. The sample size (number of leaflets) for estimating the mean population density of whitefly nymphs in soybean is 47 leaflets in scenarios of high infestation (22.1 nymphs per leaflet) and 126 leaflets in scenarios of low infestation (3.0 nymphs per leaflet), with an estimation error of 30% of the mean and a 95% confidence level. Regarding the adult stage of whiteflies, for both low infestation scenarios near the control threshold (1.9 adults per leaflet) and scenarios with higher whitefly populations (5.7 adults per leaflet), the sample size is 82 leaflets, with an estimation error of 30% of the mean and a 95% confidence level. |
id |
UFSM_723af1209ed3ae34acf51ac3ffed1886 |
---|---|
oai_identifier_str |
oai:repositorio.ufsm.br:1/30795 |
network_acronym_str |
UFSM |
network_name_str |
Manancial - Repositório Digital da UFSM |
repository_id_str |
|
spelling |
Tamanho de amostra para mosca-branca em sojaSample size for whitefly in soybeanGlycine maxBemisia tabaciPlanejamento amostralAmostragemSample designSamplingCNPQ::CIENCIAS AGRARIAS::AGRONOMIAThe whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is one of the main pest insects that infest soybean crops. It causes damage through plant sap-sucking, toxin injection, virus transmission, and secretion of a sugar-rich substance that promotes the development of sooty mold. The primary method of controlling the insect is the use of chemical insecticides. Therefore, it is essential to have knowledge of the whitefly population density in the area to determine the need and timing of application. To estimate the population density of the insect pest it is necessary to know the sample size, which is the number of soybean leaflets that should be evaluated. Therefore, the aim of this study was to establish the sample size (number of leaflets) for estimating the mean population density of nymphs and adults of the whitefly in soybean. Twentythree treatments comprising insecticides for whitefly control were evaluated in experiments conducted over two agricultural years, with soybean planting dates on December 11, 2020 (first experiment), and December 17, 2021 (second experiment), with evaluations beginning at the reproductive stages R5.4 and R5.2, respectively. The evaluations were carried out on nine dates in the first experiment and on eight dates in the second experiment. In each experiment, treatment, and date of nymph population assessment, the central leaflet from the middle third of 20 plants per plot (one leaflet per plant) was collected, and the number of nymphs was counted in the laboratory. To assess the adult stage of the whitefly, a visual count was performed in the field on the central leaflet of the upper third of 20 plants per plot (one leaflet per plant). Measures of central tendency and variability were calculated, and normality was verified. The sample size (number of leaflets) was determined based on the Student’s t-distribution. The mean population density of whiteflies was 22.1 nymphs per leaflet and 5.7 adults per leaflet in the first experiment, and 3.0 nymphs per leaflet and 1.9 adults per leaflet in the second experiment. The sample size (number of leaflets) for estimating the mean population density of whitefly nymphs in soybean is 47 leaflets in scenarios of high infestation (22.1 nymphs per leaflet) and 126 leaflets in scenarios of low infestation (3.0 nymphs per leaflet), with an estimation error of 30% of the mean and a 95% confidence level. Regarding the adult stage of whiteflies, for both low infestation scenarios near the control threshold (1.9 adults per leaflet) and scenarios with higher whitefly populations (5.7 adults per leaflet), the sample size is 82 leaflets, with an estimation error of 30% of the mean and a 95% confidence level.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESA mosca-branca, Bemisia tabaci (Hemiptera: Aleyrodidae) é um dos principais insetospraga que infesta as lavouras de soja. Causa danos pela sucção da seiva das plantas, injeção de toxinas, transmissão de viroses e secreção de substância rica em açúcar que favorece o desenvolvimento da fumagina. O principal método de controle do inseto é a utilização de inseticidas químicos. Portanto, é necessário o conhecimento da densidade populacional de mosca-branca na área, para definir a necessidade e o momento de aplicação. Para estimar a densidade populacional do inseto-praga na área de interesse, é necessário conhecer o tamanho de amostra, ou seja, o número de folíolos de soja que devem ser avaliados. Assim, o objetivo deste estudo foi determinar o tamanho de amostra (número de folíolos) para a estimação da média da densidade populacional de ninfas e adultos de mosca-branca em soja. Foram avaliados 23 tratamentos constituídos de inseticidas para controle de mosca-branca, nos experimentos instalados em dois anos agrícolas, com datas de semeadura da soja em 11 de dezembro de 2020 (primeiro experimento) e 17 de dezembro de 2021 (segundo experimento), com início das contagens de ninfas e adultos de moscabranca, nos estádios reprodutivos R5.4 e R5.2, respectivamente. As contagens foram realizadas em nove datas no primeiro experimento e em oito datas no segundo ano experimento. Em cada experimento, tratamento e data de avaliação da densidade populacional de ninfas, foi coletado o folíolo central do terço médio de 20 plantas por parcela (um folíolo por planta), e contabilizado o número de ninfas em laboratório. Para avaliação dos adultos, foi contabilizado de forma visual, a campo, o folíolo central do terço superior, de 20 plantas por parcela (um folíolo por planta). Foram calculadas medidas de tendência central e variabilidade e verificada a normalidade. Foi determinado o tamanho de amostra (número de folíolos) com base na distribuição t de Student. A média da densidade populacional de mosca-branca foi 22,1 ninfas folíolo-1 e 5,7 adultos folíolo-1 no primeiro experimento e 3,0 ninfas folíolo-1 e 1,9 adultos folíolo-1 no segundo experimento. O tamanho de amostra (número de folíolos) para a estimação da média da densidade populacional de ninfas de mosca-branca em soja é 47 folíolos em cenários de alta infestação (22,1 ninfas folíolo-1 ) e 126 folíolos em cenários de baixa infestação (3,0 ninfas folíolo-1 ), para um erro de estimação igual a 30% da média, com grau de confiança de 95%. Em relação ao estágio adulto de mosca-branca, tanto para cenários de baixa infestação e próxima ao nível de controle (1,9 adultos folíolo-1 ) quanto para cenários onde são observadas maiores populações de mosca-branca (5,7 adultos folíolo-1 ), o tamanho de amostra é igual a 82 folíolos, para um erro de estimação igual a 30% da média, com grau de confiança de 95%.Universidade Federal de Santa MariaBrasilAgronomiaUFSMPrograma de Pós-Graduação em AgronomiaCentro de Ciências RuraisCargnelutti Filho, Albertohttp://lattes.cnpq.br/0233728865094243Toebe, MarcosHaesbaert, Fernando MachadoOliveira, Lucas Boeni de2023-12-05T16:56:32Z2023-12-05T16:56:32Z2023-11-17info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://repositorio.ufsm.br/handle/1/30795porAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2023-12-05T16:56:32Zoai:repositorio.ufsm.br:1/30795Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2023-12-05T16:56:32Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Tamanho de amostra para mosca-branca em soja Sample size for whitefly in soybean |
title |
Tamanho de amostra para mosca-branca em soja |
spellingShingle |
Tamanho de amostra para mosca-branca em soja Oliveira, Lucas Boeni de Glycine max Bemisia tabaci Planejamento amostral Amostragem Sample design Sampling CNPQ::CIENCIAS AGRARIAS::AGRONOMIA |
title_short |
Tamanho de amostra para mosca-branca em soja |
title_full |
Tamanho de amostra para mosca-branca em soja |
title_fullStr |
Tamanho de amostra para mosca-branca em soja |
title_full_unstemmed |
Tamanho de amostra para mosca-branca em soja |
title_sort |
Tamanho de amostra para mosca-branca em soja |
author |
Oliveira, Lucas Boeni de |
author_facet |
Oliveira, Lucas Boeni de |
author_role |
author |
dc.contributor.none.fl_str_mv |
Cargnelutti Filho, Alberto http://lattes.cnpq.br/0233728865094243 Toebe, Marcos Haesbaert, Fernando Machado |
dc.contributor.author.fl_str_mv |
Oliveira, Lucas Boeni de |
dc.subject.por.fl_str_mv |
Glycine max Bemisia tabaci Planejamento amostral Amostragem Sample design Sampling CNPQ::CIENCIAS AGRARIAS::AGRONOMIA |
topic |
Glycine max Bemisia tabaci Planejamento amostral Amostragem Sample design Sampling CNPQ::CIENCIAS AGRARIAS::AGRONOMIA |
description |
The whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is one of the main pest insects that infest soybean crops. It causes damage through plant sap-sucking, toxin injection, virus transmission, and secretion of a sugar-rich substance that promotes the development of sooty mold. The primary method of controlling the insect is the use of chemical insecticides. Therefore, it is essential to have knowledge of the whitefly population density in the area to determine the need and timing of application. To estimate the population density of the insect pest it is necessary to know the sample size, which is the number of soybean leaflets that should be evaluated. Therefore, the aim of this study was to establish the sample size (number of leaflets) for estimating the mean population density of nymphs and adults of the whitefly in soybean. Twentythree treatments comprising insecticides for whitefly control were evaluated in experiments conducted over two agricultural years, with soybean planting dates on December 11, 2020 (first experiment), and December 17, 2021 (second experiment), with evaluations beginning at the reproductive stages R5.4 and R5.2, respectively. The evaluations were carried out on nine dates in the first experiment and on eight dates in the second experiment. In each experiment, treatment, and date of nymph population assessment, the central leaflet from the middle third of 20 plants per plot (one leaflet per plant) was collected, and the number of nymphs was counted in the laboratory. To assess the adult stage of the whitefly, a visual count was performed in the field on the central leaflet of the upper third of 20 plants per plot (one leaflet per plant). Measures of central tendency and variability were calculated, and normality was verified. The sample size (number of leaflets) was determined based on the Student’s t-distribution. The mean population density of whiteflies was 22.1 nymphs per leaflet and 5.7 adults per leaflet in the first experiment, and 3.0 nymphs per leaflet and 1.9 adults per leaflet in the second experiment. The sample size (number of leaflets) for estimating the mean population density of whitefly nymphs in soybean is 47 leaflets in scenarios of high infestation (22.1 nymphs per leaflet) and 126 leaflets in scenarios of low infestation (3.0 nymphs per leaflet), with an estimation error of 30% of the mean and a 95% confidence level. Regarding the adult stage of whiteflies, for both low infestation scenarios near the control threshold (1.9 adults per leaflet) and scenarios with higher whitefly populations (5.7 adults per leaflet), the sample size is 82 leaflets, with an estimation error of 30% of the mean and a 95% confidence level. |
publishDate |
2023 |
dc.date.none.fl_str_mv |
2023-12-05T16:56:32Z 2023-12-05T16:56:32Z 2023-11-17 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/30795 |
url |
http://repositorio.ufsm.br/handle/1/30795 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Agronomia UFSM Programa de Pós-Graduação em Agronomia Centro de Ciências Rurais |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Agronomia UFSM Programa de Pós-Graduação em Agronomia Centro de Ciências Rurais |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1805922064217931776 |