Banca de DEFESA: ERNANDES SILVA BARBOSA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.DISCENTE : ERNANDES SILVA BARBOSA
DATA : 27/07/2018
HORA: 09:00
LOCAL: Sala 01 - PPGF
TÍTULO:
Impact of herbicides on diazotrophic bacteria associated with red rice cultivation
PALAVRAS-CHAVES:
Oryza sativa, weeds, plant growth promoting microorganisms
PÁGINAS: 79
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Fitotecnia
ESPECIALIDADE: Matologia
RESUMO:
The use of microorganisms that promote plant growth has been studied as one of the strategies to increase productivity and sustainability of rice cultivation. Several factors reduce the productivity of rice crops (Oryza sativa L.), with emphasis on weeds that compete with the crop for light, water and nutrients. In this case, the use of herbicides is justified, especially when infestations lead to high losses in grain yield. The objective of this study was to evaluate the effect of selective herbicides on strains of diazotrophic bacteria associated with the rice crop, Vermelho Pequeno variety. Three experiments were carried out to evaluate the in vitro growth of bacterial strains (Herbaspirillum seropedicae, strain ZA25, ZAL95, Z67, ZAE94, 26H and Azospirillum brasilense 245) after application of the Cialofope-butyl herbicides at doses 225, 450, 675 and 900, Penoxsulam 60, 120, 180 and 240 and Quinclorac 375, 750, 1125 and 1500 g i.a ha-1; in the second, the germination of red rice seeds inoculated with diazotrophic bacteria Herbaspirillum seropedicae, strain ZA25, ZAL95, Z67, ZAE94, 26H and Azospirillum brasilense strain 245, treated with Cialofope-butyl herbicides, Penoxsulam, Quinclorac, at doses 225, 60 and 375 g ai ha-1 respectively; The third objective was to evaluate the growth and production of red rice inoculated with diazotrophic bacteria Herbaspirillum seropedicae, strains ZA25, ZAL95, Z67, ZAE94, 26H and Azospirillum brasilense strain 245 and treated with Cialofope-butyl herbicides, Penoxsulam, Quinclorac, at doses 225 , 60 and 375 g ai ha-1, respectively. The quantitative data from experiments two and three were submitted to analysis of variance by the F test and when significant the means were compared by the Scott-Knott test, at 5% probability. In the experiment a normal growth of the bacteria was observed in the control without herbicide and in the treatments that received 225, 450 and 675 g ia ha-1, 60, 120, and 180 g ia ha-1, 375, 750 and 1125 g ia ha-1 of the Cialofope-butyl herbicides, Penoxsulam and Quinclorac, respectively. In the treatments that included the highest doses of the herbicides, inhibition of the growth of the bacteria was verified, with exception of strain 245. In experiment two the variable number of roots was shown statistically different for the strain 245, in addition there was no effect of the tested herbicides. In the third experiment, in the collection performed 30 days after planting, the values of fresh root and shoot mass and dry mass of the aerial part showed a significant difference, with strains ZA25 and 245 being highlighted. Strains ZAL95, 26H and 245 were those that provided better performance for root dry mass. At harvesting, at 60 days after planting, the variables maintained the same behavior observed at the first collection. In the collection at the end of the crop cycle, significant values were found for the variables fresh and dry mass of root and grain mass, with better performance of rice plants provided by strains 245 and ZA25. Therefore, the bacterial strains were resistant to up to three times the recommended dose of all tested herbicides. The inoculation contributed to the increase in the number of roots, fresh and dry mass of shoot and root and mass of grains. Among the strains studied, ZA25 and 245 were the ones that promoted greater plant growth.
MEMBROS DA BANCA:
Interno - 1905333 - AROLDO FERREIRA LOPES MACHADO
Externo ao Programa - 019.283.890-31 - ANA CLAUDIA LANGARO - UFV
Externo à Instituição - MILER SOARES MACHADO - UFV