Nodular bacterial endophyte diversity associated with native Acacia spp. in desert region of Algeria

Abstract

Five species of Acacia (Acacia ehrenbergiana Hayne, A. nilotica (L.) Delile, A. seyal Delile, A. tortilis (Forssk.) Hayne and A. laeta Delile) indigenous to Tamanrasset (Algeria) were investigated for their nodulation status and nodular endophytic diversity. A. ehrenbergiana showed the highest nodulation ability across the different sites in this region, indicating the widespread occurrence of compatible rhizobia in the soils. Altogether 81 strains were purified. Among this endophytic strain collection, only four bacterial endophytes nodulated their respective host plants. On the basis of partial 16S rDNA sequencing, they were affiliated to Ensifer sp., Ensifer teranga, Mesorhizobium sp. and Rhizobium sp. Among the 79 non-symbiotic endophytes, 24 representative strains on the basis of PCR-RFLP profile obtained with MSPI enzyme digestion were characterized. They belonged to nine genera, namely: Paenibacillus, Ochrobactrum, Stenotrophomonas, Pseudomonas, Microbacterium, Rhizobium, Agrobacterium, Brevibacillus and Advenella. The isolated nodular endophytes in this study revealed a strong tolerance profile to salinity and high temperature. Principal component analysis confirmed that no correlation was found between bacterial tolerance to a maximum temperature of growth and soil depth of sampling. This tolerance profile was distributed over the three levels of soil depth sampling: 20, 40 and 60 cm. On the other hand, there was no relationship between in vitro tolerances of rhizobial strains to NaCl and high temperature and corresponding edaphoclimatic characteristics of the sampling sites. This study is a contribution to nodular bacterial diversity knowledge of desert African Acacia species growing in preserved ecosystems.

Maximizing seed germination in five species of the genus Acacia (Fabaceae Mimosaceae)

“…The acacia genus belongs to the Fabaceae family. The main advantage of these species is the ability to make symbiosis with soil microorganisms (rhizobium and mycorrhizae) conferring them the capacity to survive in grounds very poor in nutritional elements (Bashan et al 2012;Boukhatem et al 2016). The evaluation and improvement of germination took place under pretreatments operated by concentrated sulphuric acid at different times of immersion.…”

Unlocking the diversity and plant‐growth promoting potential of the bulk soil bacteria associated with the Saharan tree Vachellia tortilis subsp. raddiana

“…(2012) reporting the presence of Acinetobacter calcoaceticus , while Boukhatem et al. (2016) identified various microbes such as Advenella kashmirensis , Paenibacillus humicus , Paenibacillus glycanilyticus , Pseudomonas sp., and Paenibacillus sp. In addition, recently, Hnini et al.…”

“…However, there has also been some research on endophytic nodules of V. tortilis subsp. raddiana, with Fterich et al (2012) reporting the presence of Acinetobacter calcoaceticus, while Boukhatem et al (2016) identified various microbes such as Advenella kashmirensis, Paenibacillus humicus, Paenibacillus glycanilyticus, Pseudomonas sp., and Paenibacillus sp. In addition, recently, Hnini et al (2023) have reported a comprehensive inventory of endophytic nodules.…”

Más allá del nódulo: potencial agro-biotecnológico del microbioma endofítico en nódulos simbióticos de leguminosas

“…Hasta el momento se han descrito BENN en una ínfima cantidad de nódulos de leguminosas, entre ellas las de grano (Zhao et al, 2018), forrajeras (Wigley et al, 2017), recuperadoras de suelos (Zineb et al, 2016), y de algunos endemismos en peligro de extinción (Safronova et al, 2015). Los géneros bacterianos conocidos como BENN y las leguminosas de interés económico de las que se aislaron se detallan en la Tabla 1.…”