天美传媒

Ficus carica; Dried fruits; Figs; Rhizospheric bacteria; Endophytic bacteria; Microbial diversity; Plant-microbe interactions

Introduction

Ficus carica, a member of the Moraceae family, is a deciduous tree widely cultivated for its succulent fruits, known as figs. Figs have long been recognized for their nutritional composition, containing essential minerals, vitamins, and dietary fiber [1]. In addition to their dietary significance, figs are known to host a complex microbial community that influences their growth, ripening, and preservation. Among these microorganisms, bacteria have gained attention due to their diverse metabolic capabilities and potential interactions with the fruit's physiology. here is currently an increasing demand for the characterization of endophytic bacteria isolated from different parts of plants in order to improve the organic agriculture practices [2]. The current research was performed to identify both rhizospheric bacteria isolated from the rhizosphere of Ficus carica in three different sites in the north of Tunisia and endophytic bacteria isolated from dried figs. We then characterized them for a diversity of plant growth-promoting activities. The most common PGP trait for all bacteria from the three regions was siderophore production , followed by cellulase , then protease activity , then by lipases activity and lastly by solubilization of phosphates . The majority of the isolates manifested a possible adaptation to abiotic stress and unfavorable environments [3].

Methods

To investigate the microbial diversity in the dried fruits of Ficus carica, rhizospheric and endophytic bacteria were isolated. Rhizospheric samples were collected from the soil surrounding the fig tree's roots, while endophytic bacteria were obtained by surface sterilizing the fruits and isolating bacteria from their internal tissues [4]. The isolated bacteria were cultured using various selective media, followed by DNA extraction, PCR amplification of the 16S rRNA gene, and subsequent sequencing. Bioinformatics tools were employed for taxonomic classification and diversity analysis of the obtained bacterial sequences [5].

Bacteria isolation from Ficus carica rhizosphere

Bacteria isolation was carried out by the suspension of one gram of rhizosphere soil in 9 ml of sterile physiological solution, and then the tubes for each sample were shacked for 24 h at 400 rpm. Then, suspensions were diluted with physiological water in tenfold series and plated on PCA TSA, and KB media. After cultivating for 5 days at 30°C, different colonies were picked and plated in triplicate [6]

Results

The microbial exploration of dried fruits of Ficus carica revealed a remarkable diversity of rhizospheric and endophytic bacteria. Taxonomic analysis identified a wide range of bacterial phyla, including Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes [7]. Within these phyla, several genera commonly associated with plantmicrobe interactions were identified, such as Bacillus, Pseudomonas, Rhizobium, and Enterobacter. The diversity and composition of bacterial communities differed between the rhizosphere and endosphere, indicating distinct microenvironments and potential ecological roles for the bacteria within each compartment [8].

Discussion

The presence of diverse bacterial communities in the rhizosphere and endosphere of dried fruits of Ficus carica suggests intricate microbial interactions and potential functional roles in the fruit's health and development [9]. Rhizospheric bacteria are known to contribute to plant nutrient uptake, protection against pathogens, and growth promotion. Endophytic bacteria, on the other hand, can colonize the fruit's tissues and potentially influence its ripening, post-harvest characteristics, and even contribute to its aroma and flavor profiles. The identification of plant growth-promoting bacteria and those with potential antimicrobial properties among the isolated strains further emphasizes their ecological significance [10].

Conclusion

Microbial explorations of dried fruits of Ficus carica have provided valuable insights into the rhizospheric and endophytic bacterial diversity associated with these fruits. The findings highlight the complex interactions between Ficus carica and its bacterial communities, suggesting potential implications for fruit growth, development, and quality. Further research on the functional roles of these bacteria and their interactions with the fruit's physiology may pave the way for innovative strategies in fig cultivation, post-harvest preservation, and nutritional enhancement.

1. Akcil A, Erust C, Ozdemiroglu S, Fonti V, Beolchini F (2015).J Clean Prod 86: 24-36.
2. Gillespie IMM, Philip JC (2013).Trends Biotechnol31: 329-332.

,,

3. Mishra A, Malik A (2014).Bioresour Technol171: 217-226.

,,

4. Sagarkar S, Mukherjee S, Nousiainen A, Björklöf K, Purohit HJ, et al. (2013). Environ Pollut 172: 108-115.

,,

5. Lien PJ, Ho HJ, Lee TH, Lai WL, Kao CM (2015)Effects of aquifer heterogeneity and geochemical variation on petroleum-hydrocarbon biodegradation at a gasoline spill site. Adv Mater Res1079: 584-588.
6. Qin G, Gong D, Fan MY (2013). Int Biodeterior Biodegradation 85: 150-155.
7. Claus H (2014). Int Degrad 15-38.
8. Nõlvak H, Truu J, Limane B, Truu M, Cepurnieks G (2013).J Environ Eng Landsc Manag 21: 153-162.
9. Pingali PL(2012). Proc Natl Acad Sci109: 12302-12308.

,,

10. Duque Acevedo M, Belmonte Ureña LJ,Cortés García FJ,Camacho Ferre F (2020). Glob Ecol Conserv22: 902-604.