SONICATION AND VACUUM INFILTRATION ENHANCED AGROBACTERIUM RHIZOGENES MEDIATED TRANSFORMATION IN SOYBEAN

AbstractObjective: The present study involved the formulation of protocol of Agrobacterium rhizogenes-mediated transformation for the detailed study of isoflavones metabolism in soybean.Methods: Cotyledons were separated from 4-day-old soybean seedlings and infected with three different A. rhizogenes strains under various time durations of sonication, vacuum infiltration and co-cultivated on MS medium supplemented with various concentrations of acetosyringone. The induced hairy roots were established as a culture with the selection agent hygromycin B. Transgenes integrated in hairy roots were analysed at molecular level by PCR assay.Results: A. rhizogenes strain R1000 harbouring pCAMBIA1301 resulted in better transformation efficiency when compared with other strains. The optimum duration of sonication (2 min) and vacuum infiltration (2 min) enhanced the transformation efficiency up to 76.47 %.  PCR analyses revealed the integration of transgene in hairy roots lines.Conclusion:  From the present study, we could conclude that, sonication and vacuum infiltration techniques could be employed to produce genotype independent transgenic soybean hairy root lines and which could be used to study for the improved production of potent anti-cancer compounds, isoflavones in soybean.Keywords: Agrobacterium, isoflavones, soybean, sonication, vacuum infiltratio

An endophyte Paenibacillus dendritiformis strain APL3 promotes Amaranthus polygonoides L. sprout growth and their extract inhibits food-borne pathogens

Green leafy vegetables are rich sources of antioxidants and minerals, which prevent food-borne pathogen infections during our diet. This study was aimed to isolate and identify the plant growth-promoting endophytic bacterium from several plant species to enhance the growth of Amaranthus polygonoides L. and their antimicrobial potential against food-borne pathogens. Seven endophytic bacterial isolates were tested on two Amaranthus species to identify the suitable beneficial bacterium. The antioxidants capacity and antimicrobial activity of bacterial isolate (APL3) treated plants were analyzed. The bacterial isolate, APL3 showed a significantly higher growth of A. polygonoides L. than other isolates. It was identified as Paenibacillus dendritiformis strain APL3 by 16S rRNA gene sequencing and phylogenetic analysis. The endophyte (APL3) treated A. polygonoides L. sprouts had higher antioxidants potentials and significantly inhibited the growth of Escherichia coli, Salmonella sp., Staphylococcus sp. and Pseudomonas sp. The results of the present study suggest that utilization of P. dendritiformis strain APL3 triggers the growth of A. polygonoides L. and induces metabolic changes in plants to improve their antimicrobial properties to prevent foodborne pathogens

Zika Virus Encoding Nonglycosylated Envelope Protein Is Attenuated and Defective in Neuroinvasion

ABSTRACT Zika virus (ZIKV), a mosquito-transmitted flavivirus responsible for sporadic outbreaks of mild and febrile illness in Africa and Asia, reemerged in the last decade causing serious human diseases, including microcephaly, congenital malformations, and Guillain-Barré syndrome. Although genomic and phylogenetic analyses suggest that genetic evolution may have led to the enhanced virulence of ZIKV, experimental evidence supporting the role of specific genetic changes in virulence is currently lacking. One sequence motif, VNDT, containing an N-linked glycosylation site in the envelope (E) protein, is polymorphic; it is absent in many of the African isolates but present in all isolates from the recent outbreaks. In the present study, we investigated the roles of this sequence motif and glycosylation of the E protein in the pathogenicity of ZIKV. We first constructed a stable full-length cDNA clone of ZIKV in a novel linear vector from which infectious virus was recovered. The recombinant ZIKV generated from the infectious clone, which contains the VNDT motif, is highly pathogenic and causes lethality in a mouse model. In contrast, recombinant viruses from which the VNDT motif is deleted or in which the N-linked glycosylation site is mutated by single-amino-acid substitution are highly attenuated and nonlethal. The mutant viruses replicate poorly in the brains of infected mice when inoculated subcutaneously but replicate well following intracranial inoculation. Our findings provide the first evidence that N-linked glycosylation of the E protein is an important determinant of ZIKV virulence and neuroinvasion. IMPORTANCE The recent emergence of Zika virus (ZIKV) in the Americas has caused major worldwide public health concern. The virus appears to have gained significant pathogenicity, causing serious human diseases, including microcephaly and Guillain-Barré syndrome. The factors responsible for the emergence of pathogenic ZIKV are not understood at this time, although genetic changes have been shown to facilitate virus transmission. All isolates from the recent outbreaks contain an N-linked glycosylation site within the viral envelope (E) protein, whereas many isolates of the African lineage virus lack this site. To elucidate the functional significance of glycosylation in ZIKV pathogenicity, recombinant ZIKVs from infectious clones with or without the glycan on the E protein were generated. ZIKVs lacking the glycan were highly attenuated for the ability to cause mortality in a mouse model and were severely compromised for neuroinvasion. Our studies suggest glycosylation of the E protein is an important factor contributing to ZIKV pathogenicity

Cerium oxide as a nanozyme for plant abiotic stress tolerance: An overview of the mechanisms

Abiotic stress in plants is considered an important environmental constraint that ultimately reduces agricultural production. Nanotechnology is an advancing technology for improving plant growth and mitigating stress factors in modern agriculture. Cerium oxide, a rare lanthanide in Earth’s crust, holds significant potential in various industrial sectors. Research on engineered cerium oxide nanoparticles has been proven to play a significant role in promoting plant growth and alleviating environmental stress factors at lower dosage levels. The accumulation of cerium oxide nanoparticles benefits plants by improving morphological attributes, antioxidants, and photosynthetic parameters. Application of cerium oxide nanoparticles as nanozymes under abiotic stress conditions activates stress signaling cascades in plants to scavenge the reactive oxygen species (ROS) generated. However, higher dosages can lead to toxicological effects in plants. Higher accumulation of cerium oxide nanoparticles in different plant tissues is critical for reviewing their interference with the food chain and safety. This review covers the impact of cerium oxide nanoparticles on plant performance, abiotic stress tolerance, and the underlying mechanisms when interacting with plants

Chilling Resistance and Physio -Chemical Changes during Cold Acclimation in Foxtail Millet Genotypes

Millets are known as poor man crops, because they grow well in rain-fed or dry land conditions with insufficient soil fertility and water. Food shortages could become more severe in the coming years as the world population rises and arable land is depleted. As a result, various strategies are needed to ensure food security. Millets are also notable for their short growth season. They can reach maturity in as little as 85 days after being sowing. Low temperature is a major environmental factor that can limiting the plant anabolic, metabolic processes and yield globally. Temperature is an extremely important growth limiting factor because it regulates plant physiological and biochemical activity throughout the growth cycle. A field study was scheduled to estimate the low temperatures effect on plant processes such as photosynthesis, respiration, water absorption, chlorophyll stability, and yield. It was done in Rabi’ 2020 and 2021 with factorial randomized block design (FRBD) with three replications. The present study was conducted to determine the low temperature effect on growth analysis and yield of tenai genotypes screening at Agricultural College and Research Institute, Vazhavachanur. Temperature stress, particularly high or low temperatures, can disrupt plant metabolism and shorten the time of distinct plant growth phases. Plants' responses to low temperature exposure can have a significant impact on various growth parameters such as leaf area, leaf area index, crop growth rate, relative water content, photosynthetic efficiency, days to 50% flowering, number of tillers, number of grains per tiller, total dry matter production, and yield. Tenai genotypes TNSi 375 and TNSi 375 recorded higher values of specific leaf area, crop growth rate, specific leaf weight, total chlorophyll content and grain yield than other genotypes under low temperature condition, Tiruvannamali district and Jawathu hill region of Vellore district.&nbsp

Biotechnology Advances in Bioremediation of Arsenic: A Review

Arsenic is a highly toxic metalloid widespread in the Earth's crust, and its contamination due to different anthropogenic activities (application of agrochemicals, mining, waste management) represents an emerging environmental issue. Therefore, different sustainable and effective remediation methods and approaches are needed to prevent and protect humans and other organisms from detrimental arsenic exposure. Among numerous arsenic remediation methods, those supported by using microbes as sorbents (microbial remediation), and/or plants as green factories (phytoremediation) are considered as cost-effective and environmentally-friendly bioremediation. In addition, recent advances in genetic modifications and biotechnology have been used to develop (i) more efficient transgenic microbes and plants that can (hyper)accumulate or detoxify arsenic, and (ii) novel organo-mineral materials for more efficient arsenic remediation. In this review, the most recent insights from arsenic bio-/phytoremediation are presented, and the most relevant physiological and molecular mechanisms involved in arsenic biological routes, which can be useful starting points in the creation of more arsenic-tolerant microbes and plants, as well as their symbiotic associations are discussed

Sodium Nitroprusside Stimulates Growth and Shoot Regeneration in Chrysanthemum

In this study, we demonstrate that the nitric oxide (NO) donor sodium nitroprusside (SNP) improves plant regeneration in chrysanthemums. Internode explants of three different chrysanthemum cultivars, ‘White ND’,‘White wing × Peach ND’, and ‘Hunt × Lemon ND’, were cultured on shoot induction medium (SIM) containing various concentrations of N6–benzyladenine (2.22 or 4.44 μM BA) and SNP (0.83–6.71 μM) individually and in combination. Most combinations of BA and SNP significantly improved the morphogenetic potential of internode explants and enhanced shoot regeneration in all three chrysanthemum cultivars compared to treatment with BA alone. The cultivar ‘White wing × Peach ND’ displayed the highest regeneration response (98.3%) and shoot regeneration rate (27.3 shoots/explant) in SIM containing optimal BA (4.44 μM) and SNP (0.83 μM) concentrations within 30 days of culture. Individual shoots of 'White wing × Peach ND' were transferred to root induction medium (RIM) containing various concentrations of SNP (0.83–6.71 μM) alone. Shoots rooted in the presence of SNP resulted in healthy plantlets within 30 days of culture with improved root (number of roots/shoot, root length, and fresh weight) and shoot (number of leaves, shoot length, and fresh weight) growth characteristics compared to the control. In addition, the regeneration procedure described in this study only requires a short duration (60 days) to obtain rooted plantlets from internode explants of chrysanthemums. Our results suggest that supplementation of chrysanthemum regeneration medium with SNP enhances shoot regeneration and improves plant growth, overcoming problems associated with propagation and genetic transformation

Additional file 1: Table S1. of Characterization of the role of sodium nitroprusside (SNP) involved in long vase life of different carnation cultivars

Primer sequences used for detection of genes related to ethylene production and petal senescence by qRT-PCR. Figure S1. Effects of different concentrations of SNP (mg L−1) on the petal senescence of ‘Tico Viola’. The photo was taken on day 9 after the treatment. Figure S2. Effects of ACC (1 mg L−1) and ACC (1 mg L−1) + SNP10 (10 mg L−1) on the petal senescence in ‘Tico Viola’. The photo was taken on day 9 after the treatment. Figure S3. Effects of SNP (10 mg L-1) on the petal senescence of different carnation ‘Venus’, ‘Tico Tico’, and ‘Shino Lily’. Photo was taken on day 9 after the treatment. (DOCX 262 kb