Agro-Technology of Important Medicinal Plants
Namrita Lall in Medicinal Plants for Cosmetics, Health and Diseases, 2022
It grows well in a variety of soils, i.e. from sandy to loam soils. Andrographis paniculata is propagated either by seeds (Figure 25.3H) or stem cuttings. In commercial cultivation, seeds are used for raising seedlings in nurseries and transplanted in a dense plant population (222,222 plants/ha) at a spacing of 30 × 15 cm apart (Figure 25.3I). The whole plant is harvested at 90 days and the second harvesting (known as ratoon crop) is performed 60 days after the first harvest. In our previous study, the crop was found to respond with improved plant height, number of branches, number of leaves and herbage yield under biofertilizer application, i.e. Azospirillum and PSB (Patel, 2016). The crop gives an average yield of 2.0–2.5 tons dry herb yield (whole shoot system) per hectare. After harvesting plants, the drying of plants under shade conditions is highly recommended (Farooqi et al., 2001).
The Genetics of the Frankia-Actinorhizal Symbiosis
Peter M. Gresshoff in Molecular Biology of Symbiotic Nitrogen Fixation, 2018
Using complementation studies, Long et al.100 cloned genes involved in nodulation (nod genes) from R. meliloti. Later, nod genes were found in other Rhizobium strains by Southern hybridization using R. meliloti nod sequences as a probe.101-103 The genes were analyzed in detail and designated nodA, B, C, and D, the so-called "common" nod genes.104 Fogher et al.105 provided an unexpected result when they found that nodulation genes hybridized with Azospirillum DNA, suggesting that common mechanisms may exist among bacteria interacting with plants, perhaps in some of the early steps of the recognition between bacteria and plants.
Physiology of Moss-Bacterial Associations
R. N. Chopra, Satish C. Bhatla in Bryophyte Development: Physiology and Biochemistry, 2019
The symbiotic nitrogen fixation associated with the interactions of Rhizobium and Frankia with host plants needs only to be mentioned here and clearly results from complex endophytic relationships.33-35 In what may be a kind of associative (nonendophytic) symbiosis, Azospirillum lipoferum,36 Azospirillum brasilense37 and Azotobacter paspali38 are nitrogen-fixing bacteria found in association with the roots of certain tropical grasses.39 In addition to fixing nitrogen, various rhizosphere species synthesize alginates, poly-β-hydroxybutyrate, pigments, and plant hormones.40
Graphene oxide influence in soil bacteria is dose dependent and changes at osmotic stress: growth variation, oxidative damage, antioxidant response, and plant growth promotion traits of a Rhizobium strain
Published in Nanotoxicology, 2022
Tiago Lopes, Paulo Cardoso, Diana Matos, Ricardo Rocha, Adília Pires, Paula Marques, Etelvina Figueira
E20-8 strain produced IAA, and in the presence of osmotic stress, IAA content was significantly increased. Malhotra and Srivastava (2008) reported that abiotic stresses, like drought, positively increased IAA production in Azospirillum brasilense. On the other hand, Sandhya et al. (2010) observed that low osmotic potential led to a decrease in several PGP traits, including IAA. Ramos-Solano et al. (2008) reported that at relatively high osmotic stress (20% PEG) some PGPR genera successfully increased IAA production compared to control, but at the highest PEG concentration (40%), IAA levels were similar to control, registering a significantly decrease compared to the levels produced at 20% PEG. It appears that at very high osmotic stress the ability of bacteria to synthesize IAA is impaired, but at lower osmotic stress controversial data were reported, with some bacteria decreasing (Sandhya et al. 2010) and other increasing (Malhotra and Srivastava 2008) the synthesis of IAA. The ecological and agronomic advantage of increasing IAA in osmotic stress conditions is evident, since IAA promotes root growth and extends symbiotic branching, thus increasing root surface contact with soil particles, boosting water absorption and nutrients uptake (Glick 1995) and thus increasing plant tolerance in environments with low water availability (Rubin, van Groenigen, and Hungate 2017).
Nanoscale characteristics of conditioning film development on photobioreactor materials: influence on the initial adhesion and biofilm formation by a cyanobacterium
Published in Biofouling, 2021
Suvarna N. L. Talluri, Robb M. Winter, David R. Salem
On glass, the conditioning films appeared as uniformly distributed spikes having close association with one another, whereas in the case of PMMA, PC and HDPE, they appeared as isolated dot-like structures of varying heights (Figure 5). Somewhat similarly, an AFM study of the surface of a stainless-steel substratum that had been immersed in seawater (Compere et al. 2001) revealed a heterogeneous coverage of conditioning films in the form of particles of various sizes, which became denser with time. van der Aa and Dufrene (2002) studied the surface of a polystyrene substratum after the adhesion of the Azospirillum brasilense bacterium and observed the presence of dot-like structures protruding from a continuous layer of adsorbed proteins, attributed to the adsorbed proteinaceous EPS. Whereas the particulate or spike-like conditioning film morphologies that have been observed are expected to influence cell attachment by, for example, creating high surface area adhesion sites, their level of importance in ensuring effective cell attachment is not well understood. The observations in the present study of an essentially featureless conditioning film surface on PVC together with the delayed onset of cell attachment on this substratum compared with the other PBR materials, imply that the spikes or dot-like conditioning film morphologies may aid or accelerate cell attachment but are not a prerequisite.
Altered gut microbiome composition in patients with Vogt-Koyanagi-Harada disease
Published in Gut Microbes, 2020
Zi Ye, Chunyan Wu, Ni Zhang, Liping Du, Qingfeng Cao, Xinyue Huang, Jihong Tang, Qingfeng Wang, Fuzhen Li, Chunjiang Zhou, Qian Xu, Xiao Xiong, Aize Kijlstra, Nan Qin, Peizeng Yang
Immunosuppressive agents are the first choice in the treatment of VKH disease. Our results showed that the altered gut microbiome in VKH could be partially restored after immunosuppressive treatment, which coincides with resolution of intraocular inflammation. An increased abundance of bacteria negatively associated with VKH such as Alistipes sp.CAG435, Azospirillum sp.CAG260 and Proteobacteria bacterium CAG495 was observed after the treatment. A beneficial alteration seems to occur in the gut environment after the immunosuppressive treatment, although the exact mechanism is still unknown.
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