Theobroma cacao L. agricultural soils with natural low and high cadmium (Cd) in Santander (Colombia), contain a persistent shared bacterial composition shaped by multiple soil variables and bacterial isolates highly resistant to Cd concentrations

Abstract

HIGHLIGHTS This study report statistically significant differences in beta-diversity correlated with soil properties, including Cd concentrations. Culture-dependent techniques allowed the isolation of bacterial strains tolerating high Cd concentrations up to 120 mgL −1 for potencial Cd biosorption or intracellular sequestration. The combination of different approaches provides a baseline about the bacterial composition and Cd tolerant strains found in these soils influence for lower Cd accumulation in cocoa crops.

Diversity and functional assessment of indigenous culturable bacteria inhabiting fine-flavor cacao rhizosphere: Uncovering antagonistic potential against Moniliophthora roreri

“…Several isolates of Bacillus , Paenibacillus , Fictibacillus , Peribacillus , and Neobacillus genera were also found. This agrees with previous reports, which have shown the association of Bacillus with Theobroma cacao [ 14 , 23 , [45] , [46] , [47] ]. Moreover, the involvement of Bacillus in the rhizosphere has been demonstrated through plant growth-promotion attributes such as indole-3-acetic acid (IAA) production, phosphate solubilization, and biofilm development [ 48 ].…”

Bioremediation Potential of Native Bacillus sp. Strains as a Sustainable Strategy for Cadmium Accumulation of Theobroma cacao in Amazonas Region

“…Similar results were shown by [28], who reported a 62% dominance of gram-positive bacteria in a cadmium-tolerant bacteria related to T. cacao. Conversely, [56,57] reported a strong dominance of gram-negative bacteria (over 88%). This suggests that the microbial population diversity associated with Cd-alleviation is highly variable.…”

“…Refs. [66][67][68] and may be predominant at high cadmium concentrations [56]. This is probably because they produce spores that offer them the ability to tolerate a wide range of biotic and abiotic stress [69].…”

Assessment of native cadmium-tolerant bacteria in cacao (Theobroma cacao L.) - cultivated soils in Cundinamarca-Colombia

“…Cd has also been reported in cacao (Mounicou et al 2003;Chavez et al 2015;Gramlich et al 2016Gramlich et al , 2018Arévalo-gardini et al 2017). Cacao is considered a traditional exportable crop with a global production of 4.7 million tons (in 2018/ 19), of which 68% comes from developing countries (ICCO, 2021; Maddela et al 2020). The European Commission regulates the maximum limits of permissible Cd for chocolate and other derived products depending on the percentage of raw cacao present in the nal product (Commission regulation (EU) No.…”

“…from cacao-cultivated soils with Cd have been isolated (Bravo et al 2018). Recently, Cáceres et al (2021) explored the bacterial community associated with cocoa plantations in Colombia. In this study, we describe the taxonomic diversity and community structure of CdtB associated with cocoa crops in the Cundinamarca, central region of Colombia, not studied to date.…”