Soybean cultivars agronomic performance and yield according to doses of Azospirillum brasilense applied to leaves

Abstract

Alternative methods of inoculation such as the application of the bacteria Azospirillum brasilense via spray in an advanced stage of the crop can increase the soybean performance. The aim of this study was to evaluate the agronomic traits and grain yield in soybean crops through Azospirillum brasilense doses applied by spray coverage. The experiment was conducted in randomized blocks in a 4 × 6 factorial, with four cultivars (Anta 82 RR ® , BRS Favorita RR ® , BRS 780 RR ® , BRS 820 RR ® ) and six doses of Azospirillum brasilense (0, 300, 400, 500, 600, 700 mL ha -1 ) with three replications in two crop years. The characters such as plant height, shoot dry mass, chlorophyll content, leaf nitrogen content at flowering were evaluated. At harvest, the evaluated characters were plant height, height of the first pod insertion, number of pods per plant, number of grains per pod, thousand grain mass, grain yield and grain harvest index. For the conditions that this study was carried out and according to the results, the spray with different Azospirillum brasilense doses did not affect the agronomic variables studied and the grain yield in RR ® soybean cultivars.

Foliar application of Azospirillum brasilense in soybean and seed physiological quality

“…According to this fact, it can be inferred that the physiological quality of the soybean seeds, on average, does not depend on the A. brasilense inoculation dose and on the studied cultivar. Similar results were also obtained by Zuffo et al (2015a) and Zuffo et al (2015b). The authors did not observe the A. brasilense bacteria on the soybean agronomical characters.…”

Effects of plant growth-promoting rhizobacteria on co-inoculation with Bradyrhizobium in soybean crop: a meta-analysis of studies from 1987 to 2018

“…Hungria, Nogueira & Araujo (2013) investigating the effects of co-inoculation of soybean seeds with B. japonicum and A. brasilense, observed an average increase of 420 kg ha −1 (16.1%) compared to the control treatment inoculated only with B. japonicum. Conversely, Zuffo et al (2016) reported no significant differences in grain yield between inoculated (B. japonicum) and coinoculated (B. japonicum + A. brasilense) treatments for six soybean cultivars. Nevertheless, Atieno et al (2012) observed that co-inoculation of B. japonicum and B. subtilis increased traits related to soybean nodulation and biomass.…”

“…In addition to the use of rhizobia, another strategy that has been employed to increase soybean productivity is the co-inoculation of Bradyrhizobium with other genera of plant growth-promoting rhizobacteria (PGPR), such as Azospirillum (Hungria, Marco & Ricardo, 2015;Zuffo et al, 2016), Bacillus (Mishra et al, 2009;Tonelli, Magallanes-Noguera & Fabra, 2017), Pseudomonas (Egamberdieva, Jabborova & Berg, 2016;Pawar et al, 2018), and Serratia (Bai, 2002;Pan, Vessey & Smith, 2002). These microorganisms act as promoters of plant growth via the production of amino acids, indole acetic acid (IAA), gibberellins, and other polyamines, improving root growth and, consequently, increasing water and nutrient absorption by the plants and generating rhizobia-soybean interaction sites (Schmidt, Messmer & Wilbois, 2015;Yadav et al, 2017).…”

Increase of soybean yield through agricultural practices in Central Brazil

“…Another strategy used to increase crop yield is based on co-inoculation or mixed inoculation of bacteria of the genus Bradyrhizobium with bacteria that promote the Azospirillum genus plant growth (Hungria et al, 2015b;Zuffo et al, 2016). The co-inoculation technique of microorganisms with different functions can be considered economically viable and environmentally sustainable for improving crop performance (Zeffa et al, 2020).…”