Valor nutritivo da Coastcross-1 inoculada com Azospirillum brasilense

Abstract

RESUMO Objetivou-se com este trabalho avaliar a taxa de produção de forragem e o valor nutritivo da Coastcross-1, inoculada com Azospirillum brasilense, fertilizada com diferentes doses de N e submetida ao regime de corte. O delineamento experimental foi o de blocos ao acaso, com três repetições, em esquema fatorial. Os fatores foram o uso da inoculação (não inoculada, inoculada somente no plantio e reinoculada no segundo ano), níveis de N (0, 100 e 200kg/ha/ano de N) e os períodos do ano. Avaliaram-se a taxa de produção e a composição botânica da forragem, a composição morfológica, o teor de proteína bruta, a digestibilidade in situ da matéria orgânica e os nutrientes digestíveis totais da Coastcross-1. A inoculação, quando não associada ao adubo nitrogenado, ocasionou aumento na taxa de produção de forragem, na participação da Coastcross-1 e na produção de nutrientes digestíveis totais. Houve redução nos teores de proteína bruta da Coastcross-1, quando a gramínea adubada com 200kg/ha/ano de N foi inoculada. A inoculação tem efeito positivo na Coastcross-1 não submetida à adubação nitrogenada.

Productivity and nutritive value of Tifton 85 bermudagrass inoculated with Azospirillum brasilense in association with nitrogen fertilization

“…On the contrary, the absence of a difference in the nutritive value variable does not corroborate with the findings in Coastcross grass (Cynodon spp.) inoculated with A. brasilense in the same region, which showed an increase in the concentrations of CP and NDT in the pasture (Aguirre et al, 2018b).…”

Production and nutritive value of Tifton 85 bermudagrass pastures overseeded with annual ryegrass and inoculated with diazotrophic bacteria

“…and Cyperaceae spp., low participation in the pasture composition was observed, which is a reflection of the management approach adopted here, with residual pasture heights between 7 and 10 cm (Michelangeli et al ., 2010). The contribution of dead material was high in the winter due to the senescence of Tifton 85 bermudagrass, resulting from the action of the cold and frosts, and due to ryegrass maturation in the spring (Aguirre et al ., 2018).…”

“…This assumption is confirmed by the total forage yield, which did not differ between the pasture inoculated and fertilized with 180 kg N/ha and the pasture fertilized with 230 kg N/ha corroborating studies showing that A. brasilense inoculation enables a reduction between 20 and 30% in the use of nitrogen fertilizer (Pindi and Satyanarayana, 2012; Leite et al ., 2019; Duarte et al ., 2020; Hungria et al ., 2021). A superior value was obtained in pastures of the Coastcross-1 bermudagrass when it was inoculated and fertilized with 100 kg N/ha, and the forage production was equivalent to that in the pasture fertilized with 200 kg N/ha per year (Aguirre et al ., 2018).…”

“…Studies on the use of these bacteria, especially for grain production, have been conducted (Quatrin et al ., 2019; Schaefer et al ., 2019; Hungria et al ., 2021). However, few studies on forage plants, especially perennial species (Aguirre et al ., 2018), are available. The use of microorganisms, especially those with facultative endophytic associations such as Azospirillum brasilense , may be an alternative that improves the nitrogen use efficiency of pastures (Duarte et al ., 2020; Pedraza et al ., 2020; Hungria et al ., 2021).…”

“…The use of microorganisms, especially those with facultative endophytic associations such as Azospirillum brasilense , may be an alternative that improves the nitrogen use efficiency of pastures (Duarte et al ., 2020; Pedraza et al ., 2020; Hungria et al ., 2021). Therefore, a possible synergistic effect between A. brasilense and nitrogen fertilization can result in increased productivity and decreased production costs of Tifton 85 bermudagrass pasture (Aguirre et al ., 2018). The objective of this study was to evaluate the effects of A. brasilense inoculation in grazing systems based on Tifton 85 bermudagrass and its association with annual ryegrass with different levels of nitrogen fertilizer.…”