Bioprospection and genetic diversity of endophytic bacteria associated with cassava plant

Abstract

-Cassava is mostly planted in sandy soils which are usually of low fertility, thereby making it necessary to perform beneficial associations with microorganisms that can promote their growth. In this perspective, the possibility of selecting bacterial isolates efficient in promoting the growth of the culture is evident, which can provide subsidies for future inoculants. The objective of this study was to isolate, identify, select and evaluate the genetic diversity of endophytic bacteria in roots and stems of cassava grown in Garanhuns -PE, with features involved in promoting plant growth. The isolation was performed on culture medium semisolid LGI-P. The selected isolates were evaluated for the potential to fix N 2 , as the ability to produce indole acetic acid, for their ability to solubilize inorganic phosphate and produce exopolysaccharides. Some bacterial isolates had their 16S rRNA gene sequenced by the Sanger method. A total of 52 endophytic bacteria isolates were obtained from cassava. Regarding the potential to fix N 2 , 15% of the isolates were positive. As for the production of IAA, 78% of the isolates produced this phytohormone in a medium with increased L-tryptophan. Approximately 31% of the isolates were able to solubilize inorganic phosphate and 60% had exopolysaccharide. The identification of 19 isolates allowed the grouping into six bacterial genera, namely: Achromobacter, Bacillus, Burkholderia, Enterobacter, Pantoea and Pseudomonas. Cassava plants grown in Garanhuns -PE present interaction with different groups of endophytic bacteria and there are bacterial groups with several characteristics involved in promoting plant growth.Keywords: 16S rRNA. Exopolysaccharide. Indole acetic acid. Biological nitrogen fixation. P solubilization. BIOPROSPECÇÃO E DIVERSIDADE GENÉTICA DE BACTÉRIAS ENDOFÍTICAS ASSOCIADASA PLANTAS DE MANDIOCA RESUMO -A mandioca é, geralmente, plantada em solos arenosos e de baixa fertilidade, tornando eminente a necessidade da mesma em realizar associações benéficas com micro-organismos que possam auxiliar seu crescimento. Nessa ótica, é evidente a possibilidade de seleção de isolados bacterianos eficientes em promover o crescimento da cultura, os quais podem fornecer subsídios para futuros inoculantes. O objetivo deste trabalho foi isolar, identificar, selecionar e avaliar a diversidade genética de bactérias endofíticas de raízes e caules de mandioca, cultivada em Garanhuns -PE, com características envolvidas na promoção de crescimento vegetal. O isolamento foi realizado em meio de cultura semissólido LGI-P. Os isolados selecionados foram avaliados quanto ao potencial de fixar N 2 , quanto à capacidade de produzir ácido indol acético, quanto à capacidade de solubilizar fosfato inorgânico e produzir exopolissacarídeos.

The Microbiome of Cassava (Manihot esculanta)

“…According to Leite, Pereira [71] the most common genera discovered in this study were Achromobacter, Bacillus, Burkholderia, Enterobacter, Pantoea, and Pseudomonas. The majority of them demonstrated a variety of biological activities related to cassava plant growth and productivity [71]. In studies conducted by Teixeira and Vieira [72] and Teixeira, Melo [73], several…”

“…Another study from Canova, Petta [70] discovered that Paenibacillus sp. IIRAC-30 from cassava could produce a major surfactin C (Figure 2 In addition, using a similar approach, Leite, Pereira [71] discovered 24 bacterial endophytes in cassava stems. According to Leite, Pereira [71] the most common genera discovered in this study were Achromobacter, Bacillus, Burkholderia, Enterobacter, Pantoea, and Pseudomonas.…”

“…IIRAC-30 from cassava could produce a major surfactin C (Figure 2 In addition, using a similar approach, Leite, Pereira [71] discovered 24 bacterial endophytes in cassava stems. According to Leite, Pereira [71] the most common genera discovered in this study were Achromobacter, Bacillus, Burkholderia, Enterobacter, Pantoea, and Pseudomonas. The majority of them demonstrated a variety of biological activities related to cassava plant growth and productivity [71].…”

“…The most prevalent bacteria found in cassava root were Bacillus, Burkholderia, Enterobacter, and Pantoea. The majority of them possessed biological properties, including the ability to solubilize inorganic phosphate and the capacity to synthesize Indole acetic acid [71].…”

Bioprospecting of endophytic bacteria (Bacillus spp.) from passionfruit (Passiflora edulis Sims f. flavicarpa) for plant growth promotion

“…Thus, studies have been developed using microorganisms with capability of promoting plant growth such as endophytic bacteria. Plant-growth-promoting endophytic bacteria have been reported as hosts in various agricultural crops and not cultivated plants, living in symbiosis with plants such as passionfruit (Passiflora edulis) (Santos et al, 2017), sugarcane (Saccharum officinarum L.) (Silva et al, 2015), (Manihot esculenta Crantz) (Leite et al, 2018), elephant grass (Pennisetum purpureum Schumach) (Li et al, 2016), among others. These studies strengthen the recognition of these as important agents in agriculture.…”