Data/hora: 10/06/2024 13:56:09

Provedor de dados: | 65
País: | Brazil
Título: | Critical-point models to relate yield and disease intensity of the multiple pathosystem in rice leaf spots disease
Autores: | Bordin,Luiz Carlos; Casa,Ricardo Trezi; Marcuzzo,Leandro Luiz; Reis,Erlei Melo; Gheller,André; Zancan,Rômulo Luís; Fingstag,Maiquiel Diego.
Data: | 2016-01-01
Ano: | 2016
Palavras-chave: | Oryza sativa; Pyricularia oryzae; Bipolaris oryzae; Gerlachia oryzae; Damage.
Resumo: | ABSTRACT: The occurrence of leaf spots in irrigated rice can reduce the yield and compromise the quality of the grain. However it is unknown the economic damage threshold (EDT) that these spots cause the yield of crop. The objective of this study was to obtain damage functions for models of critical, to relate damage by simultaneous occurrence of blast, brown spot and scald spot with grain yield harvests in 2011/12 and 2012/2013, in Rio do Oeste, Santa Catarina State, Brazil. Gradient of diseases intensity was generated by number of applications and fungicides rates. Design was a randomized block with four replications and six treatments consisting of mixing fungicide applications of triazole (difenoconazole) and strobilurin (azoxystrobin). In 2011/12 and 2012/13 growing season were made two and three tests respectively with the same experiment. Before each application it was determined the incidence and severity of fungal diseases. The critical point models were obtained by linear regression between grain yield and incidence (I) and severity (S). In 2011/12 the functions were not significant at the beginning of tillering and 2012/2013 harvest resulted in R=13.404-92.98I and R=10.685-3.804S. Respectively in each harvest resulted in tillering (R=9.141-103.6I; R=7.605-1.538 and R=8.864-73.91I; R=7.202-77S), panicle initiation (R=9.432-188.5I; R=7.,038-1.466S and R=10.176-87.33I; R=8.258-533.55S), booting (R=7.044-71.78I; R=6.881-1.296S and R=9.993-71.74I; R=8.846-763.83S), flowering (R=7.447-82.29I; R=8.731-1.398S and R=8.347-54.36I; R=7.338-681.52S) and milky grain (R=10.143-80.5I; R=7.522-1.402S and R=8.661-60.063I; R=9.754-1.465S). The generated functions allow getting the damage coefficient for use in the calculation of EDT in multiple pathossystem leaf spots in irrigated rice.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000100007
Editor: | Universidade Federal de Santa Maria
Relação: | 10.1590/0103-8478cr20150310
Formato: | text/html
Fonte: | Ciência Rural  v.46 n.1 2016
Fonte: | info:eu-repo/semantics/openAccess