Seasonal deviation effects foliar endophyte assemblage and diversity in Asparagus racemosus and Hemidesmus indicus

Abstract

BackgroundFungal endophytes are the living symbionts which cause no apparent damage to the host tissue. The distribution pattern of these endophytes within a host plant is mediated by environmental factors. This study was carried out to explore the fungal endophyte community and their distribution pattern in Asparagus racemosus and Hemidesmus indicus growing in the study area.ResultsFoliar endophytes were isolated for 2 years from A. racemosus and H. indicus at four different seasons (June–August, September–November, December–February, March–May). A total of 5400 (675/season/year) leaf segments harbored 38 fungal species belonging to 17 genera, 12 miscellaneous mycelia sterile from 968 isolates and 13 had yeast like growth. In A. racemosus, Acremonium strictum and Phomopsis sp.1, were dominant with overall relative colonization densities (RCD) of 7.11% and 5.44% respectively, followed by Colletotrichum sp.3 and Colletotrichum sp.1 of 4.89% and 4.83% respectively. In H. indicus the dominant species was A. strictum having higher overall RCD of 5.06%, followed by Fusarium moniliforme and Colletotrichum sp.2 with RCD of 3.83% and 3%, respectively. Further the overall colonization and isolation rates were higher during the wet periods (September–November) in both A. racemosus (92.22% and 95.11%) and H. indicus (82% and 77.11%).ConclusionStudy samples treated with 0.2% HgCl2 and 75% EtOH for 30 s and 1 min, respectively, confirmed most favorable method of isolation of the endophytes. Owing to high mean isolation and colonization rates, September–November season proved to be the optimal season for endophyte isolation in both the study plants. Assessing the bioactive potential of these endophytes, may lead to the isolation of novel natural products and metabolites.

WITHDRAWN: Preliminary study on seasonal diversity of root endophytic fungi and bacteria associated with sainfoin (Onobrychis viciifolia) in South Africa

“…This indicates that the diversity of fungi associated with sainfoin roots is in uenced by seasonality as it varies between seasons, with a higher diversity and isolation rate during the wet season. Similar results were reported byRather et al (2018) andHuang et al (2008), who also found a greater diversity and isolation rate of endophytic fungi associated with both Indian sarsaparilla and shatavari and various Chinese tropical medicinal plants, respectively, during the wet season compared to other seasons of the year. This seasonal variation might be a result of multiple factors, including differences in the temperature, relative humidity and precipitation between seasons, as well as changes in the stage of plant growth, vegetation, and soil(Rather et al.…”

“…2018; Chen et al 2020). In particular, the higher precipitation during wet seasons affects the ecological niche of the habitat and promotes the dispersion of fungal spores (Rather et al 2018; Chen et al 2020).Additionally, the moderate temperature of wet seasons increases the viability of these fungal spores for successive plant colonisation(Rather et al 2018). As a result, the precipitation and temperature levels of wet seasons might be more suitable for fungal growth, whereas dry seasons might have less favourable conditions, thereby reducing growth and colonisation.Overall, during this study 34 bacterial isolates were obtained from surface-sterilised sainfoin roots -10 during the dry season and 24 during the wet season, consisting of 4 and 12 genera, respectively.During the dry season, the most dominant bacterial genus isolated from sainfoin roots was Paenibacillus, which accounted for 50% of the obtained bacterial isolates, followed by Peribacillus and Rathayibacter with 20% each.…”

Apple endophyte community is shaped by tissue type, cultivar and site and has members with biocontrol potential againstNeonectria ditissima

“…This may result in a different response of plant‐associated microbiota to region variability. Season influenced the abundance of actinobacteria and proteobacteria in branches of different tree species Acer negundo (Manitoba Maple) , Ulmus pumila (Siberian Elm) and U. parvifolia (Chinese Elm) (Shen and Fulthorpe ) and bacterial and fungal endophytic colonization and/or isolation rate in other plant species related to temperature and wetness period and growth stage of the tissue (Mocali et al ; Guo et al ; Rather et al ; Sadeghi et al ). In contrast to these other studies, the smaller amount of variation according to region and season is likely to have been partially due to solely woody stems, the infection court of the pathogen, being assessed.…”

“…This indicates that the apple endophyte community is closely related to cultivar and even the disease resistance characteristics of the cultivars. The effect of other factors (tissue type, site, region and season) on the apple endophyte community remains unknown, although they have been found to influence endophyte communities in other plant species (Arnold et al ; Knief et al ; Peršoh ; Rather et al ). Members of the endophyte communities are increasingly being targeted as a source of potential biocontrol agents for plant diseases (Lodewyckx et al ; Backman and Sikora ; Eljounaidi et al ).…”

Bioprospecting endophytic fungi from Fusarium genus as sources of bioactive metabolites

“…All the evidence are showing today that endophytes, especially fungal endophytes play important beneficial roles in host plant development and physiology including increased stress tolerance, enhanced root growth and provision for special nutrition and water (Wani et al 2015). This is also true for Fusarium species frequently isolated as an endophyte in a wide-varied host (Rather et al 2018;Strobel 2018). Data presented above are supporting the ability of Fusarium species as an important component of the host plant and confirmed the potentiality of using these endophytic species to limit the effect of abiotic stresses on crop plants and improve the production yield.…”