PDF | The corn crop is one of the most cultivated in the world and of corn crop, in function of foliar Azospirillum brasilense inoculation, associated with nitrogen doses. capacidade de expansão do grão em milho-pipoca. Inoculação de Azospirillum brasilense e doses de nitrogênio em milho para In this context, the use of bacteria of the genus Azospirillum brasilense appears. inoculation with Rhizobium tropici in the absence of N fertilization was efficient Crescimento do milho em resposta a Azospirillum brasilense.
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Plant growth promoting bacteria are beneficial bacteria found in the rhizosphere, though they can also be found colonizing roots and internal tissues. This study aimed at evaluating the effects of an inoculant with Azospirillum brasilense on the growth and yield of secondharvest maize. These bacteria improve conditions for development of root system as they synthesize phytohormones, allowing absorption of more water and nutrients, as well as providing more tolerance against drought and salinity stresses Bashan et al.
The capacity of these bacteria to fix nitrogen allows them to promote plant growth Hungria et al.
These results highlight the significant effects of nitrogen on the development of maize crop, because nitrogen provides a significant increase in leaf area and in the production of dry matter weight, resulting in greater grain yield Escosteguy et al. To estimate the grain yield of the culture, all ears from the usable area of each plot were collected, and then threshing was performed with the aid of a manual thresher.
In the assessment of ear insertion height and plant total height on the plot usable area, measurements were taken from milyo soil surface to the insertion of the ear and by the end of the stalk, respectively. In addition, nitrogen topdressing fertilization, associated with the use of inoculation, has reduced yield and the shoot dry biomass production. All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License.
Thirty-six seeds were sown per azospiriolum in an attempt to establish a population of 60, plants ha According to Hungria et al. Azospirilum inoculation increases maize height and stem diameter, chlorophyll content and dry biomass weight for the shoot and root system, as well as 1,grain weight, ear length and grain yield, when the maize is inoculated via seed or leaf. There was evaluated the height of ear insertion, total plant height, leaf N content, shoot dry biomass and grain yield.
Characterization of diazotrophic bacteria associated with maize: The chemical characteristics of the cm soil layer prior to planting were: By the other hand, it is agreed that plant genotype is the key millho to obtain the benefits derived from biological nitrogen fixation, combined with the selection of efficient strains.
The regression analyses indicate a growing response to treatments with increasing doses of N for weight of 1, seeds.
The effects of N doses were only significant for 1,grain weight and grain yield kg ha -1with seed inoculation providing a higher yield for second-harvest maize. Based on the mean moisture content of the sample, the dry biomass produced in each plot was calculated, then extrapolating to kg ha Increased leaf N content, found in this study, may have enhanced the effects of nitrogen in plant development, since the formation of grain in maize azospirilluum is closely related to the translocation of sugars Crawford et al.
However, in the second harvest, the cover fertilization in association with inoculation reduced yield. In order to do so, a measurement ruler was used for surveying. Plant heights cm at 30 and 60 azospurillum after sowing are shown in Table 1. There was no statistical difference in this stage of development for doses of mineral N at 60 days.
Responses of agronomically important crops to inoculation with Azospirillum Australian. I Agronomist Engineer, Doctor Science.
Journal of Plant PhysiologyHobart, v. The dataset was subjected to an analysis of variance using the Biostat 5.
Inoculated plants showed a greater growth for height 9. Brazilian Archives of Biology and TechnologyCuritiba, v. However, it still presents a significant yield increase Figure 3. Quadrosin an experiment under tillage with the intent to assess the inoculation of maize genotypes with Azospirillum spp. Thus, the objective of this work was to evaluate the development and yield of maize in response to inoculation with Azospirillum spp.
Hartmann A Ecophysiological aspects of growth and nitrogen fixation in Azospirillum spp. In both seasons, the ear insertion height and total plant height were not affected by the factors under study. As for the grain yield, the addition of 1. Use of a chlorophyll meter at the early dent stage of corn to evaluate N sufficiency. These results exceed those obtained by Cavallet et al.
At this point, plants may not have azospirillhm time to express the effect of the inoculation. Several reports in the literature discuss the capacity of Azospirillum to produce phytohormones that stimulate root growth in several plant species Dobbelaere et al.
On average, both the seed and leaf-spray inoculated treatments showed longer ear lengths, in comparison with the non-inoculated control.
This result surpassed that found by Kappes et al. Trait Seeds Leaf-spray Control Shoot biomass g 1, Further studies on the interaction of nitrogen fertilization and its influence on the development of maize culture under inoculation with Azospirillum spp.
The lack of response to leaf-spray inoculation may be related to the fact that this treatment was only applied 20 days after sowing. Leaf N content was determined using the method described by Tedesco et al. One alternative to reduce the impact of chemical fertilizers is the use of inoculants containing nitrogen-fixing and plant growth promoting bacteria. This indicates its efficiency in increasing crop yield.
An increase in the dry biomass of both the shoots and roots of the plant caused by Azospirilum was also found by Dalla Santa et al. However, conflicting results are also found in the literature. The high cost of chemical fertilizers and concerns about more sustainable and less polluting agriculture have led to increasing interest in the use of inoculants containing bacteria that promote plant growth and enhance crop yield Hungria et al.
Inoculation with Azospirillum, associated with nitrogen fertilization in maize
The experimental plots consisted of 12 lines 12 m long, with 0. When significant difference was found in the Mmilho dosage interaction with inoculations, a regression analysis was carried out. In the same way, Quadros have found increases of up to kg ha -1 on the yield of dry weight of maize shoots, when seeds were inoculated with A.
Two experiments were conducted in the field on the summer harvest.