Nodulation, gas exchanges and production of peanut cultivated with Bradyrhizobium in soils with different textures

Abstract

Nitrogen fertilization from biological source is an uncommon practice for peanut growers due to the limited results, mainly in environments with water restriction. In this study, the response of a commercial Bradyrhizobium was evaluated on the nodulation and production of peanuts grown in sandy and medium textured soils. Two experiments using different soils were carried out in the field during the dry season, in Campina Grande, Paraíba State, Brazil. Three peanut genotypes were submitted to the following treatments: 1-no nitrogen fertilization (control), 2- chemical fertilization (ammonium sulfate) and 3- inoculation with Bradyrhizobium [commercial strain BR 1405 (SEMIA 6144)]. A completely randomized 3x3 factorial design was adopted with five repetitions for both experiments. The evaluates variables were: height of the main stem, number of nodes/plant, root length, root dry weight, weight of pods/plant and number of pods/plant. In addition, gas exchanges were estimated using IRGA apparatus. Both genotypes (BRS Havana and L7 Bege) were benefited in relation to production due to an inoculation with SEMIA 6144. No physiological response was verified in genotypes or N-treatments to gas exchange, excepting for the Ci/Ca ratio in the medium textured soil experiment. BRS Havana showed low Ci/Ca ratio in Bradyrhizobium treatment, indicating that SEMIA 6144 improved the plants photosynthetic efficiency.

Can Bradyrhizobium strains inoculation reduce water deficit effects on peanuts?

“…The inoculation of Bradyrhizobium showed different effects on the peanut varieties, both in the physiological and plant growth parameters. This results variation is expected since there is a strong interaction between the plant genotype and the inoculated bacterium, as already observed for tropical legumes such as cowpea (Marinho et al 2014(Marinho et al , 2017Alcântara et al 2014) and peanut (Melo et al 2016).…”

“…Peanut is able to associate efficiently with different rhizobial strains (Melo et al 2016), presenting higher efficiency the Bradyrhizobium genus (Valetti et al 2016;Santos et al 2017a). During the last years, some studies have been carried out in Brazil aiming to evaluate the biodiversity (Lyra et al 2013;Torres-Júnior et al 2014;Santos et al 2017a), the symbiotic efficiency (Torres-Júnior et al 2014;Santos et al 2017a, b), and the agronomic efficiency of new rhizobium strains (Sizenando et al 2016).…”

Bacilli Rhizobacteria as Biostimulants of Growth and Production of Sesame Cultivars under Water Deficit

“…In the analysis of the nitrogen content in the leaf tissue, an increase was observed in all treatments that had the water deficit condition for the two cultivars investigated ( Figure 7 ). This accumulation of nitrogen in leaves in the final phase of the experiment may imply a deficiency in the reallocation of this nutrient since it is required for photosynthesis and gas exchange, in addition to fruit formation, influencing the behavior of plants under water deficit [ 45 ]. Studies carried out with nitrogen application at different phenological stages of sesame plants showed differences in nitrogen partitioning and remobilization [ 46 ].…”

Research Article <i>Bradyrhizobium</i> spp. as attenuators of water deficit stress in runner peanut genotypes based on physiological and gene expression responses

“…The use of rhizobia, bacteria that induce the development of root and/or stem nodules in legumes, has been an alternative to optimize agricultural production through a reduced need for nitrogen fertilizers. In addition to nitrogen fixation, the rhizobium-legume interaction may contribute to host resistance to abiotic stresses such as drought, as has been demonstrated for tropical legumes such as cowpea (Oliveira et al, 2012) and peanut (Melo et al, 2016;Barbosa et al, 2018).…”