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Harnessing the power of nature, this study delves into the remarkable influence of biosynthesized silver nanoparticles (AgNPs) on biomass production and bioactive chemical synthesis in Ricinus communis callus. Leveraging the eco-friendly properties of Calligonum comosum leaf aqueous extract as both reducing and capping agents, the synthesis of AgNPs was meticulously characterized through an array of analytical techniques, including FTIR, UV-vis spectroscopy, XRD, SEM, TEM, and EDS, confirming the triumphant creation of biogenic AgNPs. Unveiling a landscape of possibilities, the assessment of R. communis biomass and phytochemical substances unraveled intriguing insights. Results unveiled a resounding enhancement in biomass production upon the introduction of biosynthesized AgNPs to the plant media. Noteworthy is the revelation that increasing concentrations of silver NPs acted as catalysts for heightened plant growth and enriched physiological parameters. Moreover, the application of silver nitride elicited a profound amplification in both biomass and antioxidant enzyme activities within plant cells. However, amidst these triumphs, a curious observation emerged: the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) exhibited a notable decline with escalating doses of AgNPs. In essence, this groundbreaking study not only underscores the potential of biosynthesized AgNPs to orchestrate a symphony of growth and biochemical synthesis within R. communis callus but also beckons forth an era of exploration. By charting a course for future research, it beckons scientists to delve deeper into the intricate pathways of phytochemical production and bioactive molecule synthesis under the influence of AgNPs.

Unfavorable environmental conditions pose a major barrier to sustainable agriculture. Among the various innovative strategies developed to protect plants from abiotic stress, the use of phytohormones and nanoparticles as “stress mitigators” has emerged as one of the most important and promising approaches. The objective of this study was to observe the protective role of melatonin (Mel) and silicon oxide nanoparticles (SiO-NPs) in rice (Oryza sativa L.) seedlings under cadmium (Cd) stress. Rice seedlings have reduced growth and phytochemical attributes when grown in Cd-contaminated (0.8 mM) pots. Seedlings under Cd stress had 38% less shoot length (SL), 53% total soluble sugar (TSS) and 57% protein content. However, superoxide dismutase (SOD), hydrogen peroxide (H2O2) and malondialdehyde (MDA) increased by 51%, 37% and 34%, respectively, under Cd stress. Beside this, activities such as peroxidase (POX) also elevated in the plants subjected with Cd-stress. In contrast, Mel (100 µm) as foliar spray and SiO-NPs (100 mg/L) as root dipping reduced oxidative stress in rice seedlings under Cd stress by reducing reactive oxygen species (ROS) generation. Furthermore, the application of Mel and/or SiO-NPs significantly increased the activity of antioxidative enzymes that scavenge ROS. The combined application of SiO-NPs and Mel increased growth, gas exchange and photosynthetic attributes, chlorophyll value, and protein content. It causes alleviation in the activity of SOD, CAT and POX by 73%, 62% and 65%, respectively. Overall, this study findings show that Mel and/or SiO-NPs can potentially protect the rice crop against oxidative damage under Cd stress.

Weeds present a significant hazard to crop production, necessitating the development of effective and sustainable strategies for weed management. Although synthetic herbicides are effective, concerns about their environmental and health impact have been raised. This study investigates the allelopathic potential, antimicrobial activity, and phytochemical profile of Artemisia monosperma. Extracts from A. monosperma proficiently impede the growth of Chenopodium murale and Amaranthus viridis, while exhibiting varying effects on crops Solanum lycopersicum and Cucumis sativus. Leaf and seed extracts demonstrate the most significant inhibition of weed growth. Interestingly, the leaf extract at a concentration of 50% inhibited weed growth in pot experiments without affecting crop growth. Moreover, extracts from A. monosperma exhibit noteworthy antifungal and antibacterial activity, with the root extract demonstrating the strongest inhibition. The root extract inhibited the mycelial growth of Colletotrichum musae by 63% as compared to control. The leaf extract exhibited the highest levels of phenolic acids, in particular gallic acid, amounting to 116.30 ppm. This study emphasizes the multifaceted potential of A. monosperma as a sustainable solution for weed management and proposes its use in crop protection. Further investigation of its practical applications and optimization of extraction methods can aid in its integration into contemporary agricultural systems, promoting both crop yield and environmental sustainability.

The Reactive carbonyl species (RCS) like, 3-deoxyglucosone (3-DG) is a highly reactive intermediate of the glycation reaction which may result into the formation of protein advanced glycation end-products (AGEs), like myoglobin-AGEs (Mb-AGEs) which further lead to the structural perturbations. In the present work, we studied the glycation of myoglobin (Mb) by physico-chemical techniques and the resulting immunogenicity by ELISA techniques. The level of free lysine and arginine determined was found to be significantly decreased indicating the establishment of the glycation reaction. The glycated myoglobin (G-Mb) shows the increased absorbance at 280 nm and enhanced fluorescence emission at 350 nm excitation wavelengths. The levels of ketoamine and hydroxymethylfurfural (HMF) were recorded to be enhanced in G-Mb when compared to its native conformer. Furthermore, the New-Zealand white female rabbits immunized with native and its glycated analogue ‘G-Mb’ induced high titer antibodies as compared to the native one.

Plectranthus amboinicus (Lour.) Spreng is a perennial plant from the mint family with aromatic, succulent leaves and several health benefits. Multiple shoot regeneration was accomplished in vitro using nodal segments (NS) explants of P. amboinicus pretreated with 0, 0.5, 5, 25, 50, and 100 μM thidiazuron (TDZ) for 4 h, then transferred to a growth regulator-free media. After 8 weeks of growth, NS explants pre-treated with 25 μM TDZ for 4 h and then transferred to TDZ-free Murashige and Skoog (MS) media produced the greatest number of shoots (27.3 per NS) with the longest average shoot length (4.9 mm) in 97.2% of cultures. On the same medium, regeneration of roots in most of the P. amboinicus shoots occurred spontaneously. The in vitro-regenerated P. amboinicus plantlets were adequately hardened off and adapted to the ex-vitro environment with a 90% survival rate. Total phenolic, tannin, and flavonoid contents, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging/antioxidant activity, were significantly higher in in vitro-regenerated plants than in ex vitro-plants. Flow cytometry (FCM) analysis validated the nuclear genome stability of the in vitro generated plants, which assessed their nuclear DNA content and found it to be comparable in genome size to that of the field-grown plants. The study found a quick and efficient method for in vitro multiplication of P. amboinicus which can aid to increased availability and accessibility of this plant species for various purposes. The genetic and phytochemical analysis of the in vitro propagated plants can also provide valuable insight into the plant’s properties and potential applications, which can further assist in its preservation and sustainable usage.

The use of nanoparticles (NPs) in agricultural fields has risen to a level where people are considering NPs as an alternative to commercial fertilizers. The input of copper oxide NPs (CuO NPs) as seed primers was investigated in this study, and the growth indices of Brassica juncea such as phenotypic parameters, photosynthetic attributes, and biochemical parameters were measured during maximum vegetative growth stage, i.e., at 45 days after sowing. Surface sterilized seeds were soaked in varying concentrations (0, 2, 4, 8 and 16 mg/L) of CuO NPs for 15, 30, and/or 45 min. After those priming periods, the seeds were planted in pots and allowed to grow naturally. Among the different tested concentrations of CuO NPs, 4 mg/L of CuO NPs for 30 min seed priming proved to be best, and considerably increased the, shoot length (30%), root length (27%), net photosynthetic rate (30%), internal CO2 concentration (28%), and proline content (41%). Besides, the performance of the antioxidant enzymes, viz, superoxide dismutase, catalase, peroxidase, and biochemical parameters such as nitrate reductase and carbonic anhydrase were also increased by several folds after the application of CuO NPs in B. juncea. The present study suggests that CuO NPs can be effectively used to increase the performance of B. juncea and may also be suitable for testing on other crop species.

The coral tree (Erythrina variegata) is a multipurpose horticultural plant with a plethora of medicinally important alkaloids. Regeneration via tissue culture can provide an efficient alternative to seed-grown plantlets and reduce the cost of the plant significantly. Thidiazuron (TDZ) is an efficient plant growth regulator and is effective in numerous species. However, the response to it varies with the type and position of the tissue on the plantlet treated. This study was carried out to ascertain the best tissue types for micropropagation of the coral tree using TDZ. Three tissue types (shoot tip, nodal, and hypocotyl), originating from different strata of the plantlet were evaluated. Adventitious shoots were observed in all three explants at the tested concentrations. However the quality and the shoot number varied significantly with the type of explant. Explants with a meristematic zone (shoot tip and nodal) were more responsive to the treatment compared with hypocotyl tissue lacking preexisting meristem. Nodal explants produced the maximum number of shoots (about eight) per explant after 4 weeks of culture, whereas shoot tips produced about only five shoots per explant at an equimolar concentration (1.5 µm). Approximately three shoots were observed in hypocotyl explants. Moreover, growth and rooting of the regenerated shoots was influenced by the origin of the explants. The molecular characterization of the regenerants using intersimple sequence repeat (ISSR) markers revealed genetic homogeneity among regenerants. An efficient micropropagation method for the coral tree is described.

Abstract Background Salinity is one of the damaging abiotic stress factor. Proper management techniques have been proposed to considerably lower the intensity of salinity on crop growth and productivity. Therefore experiments were conducted to assess the role of improved nitrogen (N) supplementation on the growth and salinity stress tolerance in wheat by analyzing the antioxidants, osmolytes and secondary metabolites. Results Salinity (100 mM NaCl) stress imparted deleterious effects on the chlorophyll and carotenoid synthesis as well as the photosynthetic efficiency. N supplementation resulted in increased photosynthetic rate, stomatal conductance and internal CO2 concentration with effects being much obvious in seedlings treated with higher N dose. Under non-saline conditions at both N levels, protease and lipoxygenase activity reduced significantly reflecting in reduced oxidative damage. Such effects were accompanied by reduced generation of toxic radicals like hydrogen peroxide and superoxide, and lipid peroxidation in N supplemented seedlings. Antioxidant defence system was up-regulated under saline and non-saline growth conditions due to N supplementation leading to protection of major cellular processes like photosynthesis, membrane structure and function, and mineral assimilation. Increased osmolyte and secondary metabolite accumulation, and redox components in N supplemented plants regulated the ROS metabolism and NaCl tolerance by further strengthening the antioxidant mechanisms. Conclusions Findings of present study suggest that N availability regulated the salinity tolerance by reducing Na uptake and strengthening the key tolerance mechanisms.

Plectranthus amboinicus (Lour.) Spreng is a medicinally important aromatic perennial herb used for the treatment of skin diseases, constipation, asthma, flu, fever, cough, and headache as well as a flavoring ingredient in traditional drinks, food, and meat stuffing. In this study, a high-performance in vitro propagation system of P. amboinicus through direct shoot organogenesis was developed using axillary node explants cultured on MS (Murashige and Skoog) medium augmented with 0.5, 2.5, 5.0, 7.5, and 10.0 µM of 6-benzyladenine (BA) or kinetin (Kin), alone or with 0.1, 0.5, 2.5, and 5.0 µM of indole-3-acetic acid (IAA) or α-naphthalene acetic acid (NAA). To optimize the regeneration potential of node explants, the effects of basal media strength and pH were also investigated. After 8 weeks of culture, explants cultured in full strength MS basal medium (pH 5.7) with 5.0 µM BA and 2.5 µM NAA exhibited the highest percentage (97.1%) of regeneration and the maximum number (19.3) of shoots per explant. Individual elongated shoots were rooted on half strength MS basal medium containing 0.25 µM indole 3-butyric acid (IBA) after 4 weeks of culture, producing 5.3 roots/shootlets with a root induction frequency of 93.7%. First time genetic stability of in vitro raised P. amboinicus plants was determined using SPAR markers, such as DAMD and ISSR, as well as flow cytometric tests, assuring the availability of authenticated raw materials for commercial production of the plant and its bioactive components.

Efficient methods for callus induction and the high-frequency plant regeneration of Ruta chalepensis L. were established, and the phytochemical potential and antioxidant activity of a donor plant, ex-vitro-established micropropagated plants, and callus were also studied. Yellowish-green callus was induced with a frequency of 97.8% from internode shoot segments of the donor plant growing in soil in the botanical garden cultured on Murashige and Skoog (MS) medium containing 10 μM 2,4-D (2,4-dichlorophenoxyacetic acid) and 1 μM BA (6-benzyladenine). Adventitious shoots were regenerated from the yellowish-green callus on MS medium containing 5.0 μM (BA) and 1.0 μM 1-naphthaleneacetic acid (NAA), with a regeneration frequency of 98.4% and a maximum of 54.6 shoots with an average length of 4.5 cm after 8 weeks. The regenerated shoots were rooted in a medium containing 1.0 μM IBA (indole-3-butyric acid) and successfully transferred to ex vitro conditions in pots containing normal garden soil, with a 95% survival rate. The amounts of alkaloids, phenolics, flavonoids, tannins, and antioxidant activity of the ex-vitro-established micropropagated plants were higher than in the donor plant and callus. The highest contents of hesperidin and rutin (93.3 and 55.9 µg/mg, respectively) were found in the ex-vitro-established micropropagated plants compared to those obtained from the donor plant (91.4 and 31.0 µg/mg, respectively) and callus (59.1 and 21.6 µg/mg, respectively). The genetic uniformity of the ex-vitro-established micropropagated plants was appraised by the ISSR markers and compared with the donor plant. This is the first report describing the callus-mediated plant regeneration, as well as the production of phenolic compounds and antioxidant activities in R. chalepensis, which might be a potential alternative technique for the mass propagation and synthesis of bioactive compounds such as hesperidin and rutin.

A high throughput regeneration protocol has been developed for Lagerstroemia speciosa through node explants under the regime of various plant growth regulators (PGRs). This protocol can provide an alternative mode to seed-grown plants and minimize the cost–time of regeneration, significantly. Murashige and Skoog (MS) medium containing various combinations of PGRs exhibited a marked stimulatory effect on morphogenesis. Of the various combinations tried, node explant pretreated with thidiazuron (TDZ; 5.0 µM) for 4 weeks and followed with transfer into MS medium containing 1.0 μM 6-benzyladenine (BA) and 0.25 μM α-naphthalene acetic acid (NAA) was reported to be the best treatment as it resulted in a maximum number of 24.5 shoots with an average shoot length of 7.1 cm per explant in 90% of cultures after 12 weeks of incubation. The in vitro-generated shoots rooted satisfactorily in the adopted ex vitro method of rooting, which saves time and cost. Among the different treatments, the greatest rooting percentage (85%) was observed in the 200 μM IBA-treated shoots, with the highest root number (8.7) and length (3.4 cm) occurring after 4 weeks. Four months after being transferred to ex vitro, some of the physiological attributes of the in vitro-propagated plants were examined and compared to the ex vitro plants. Further, analysis of the genetic integrity in tissue culture-raised plantlets along with the parental tree was accomplished through DNA-based RAPD technique. The monomorphic banding pattern obtained by the RAPD primers resulted in a high level of genetic uniformity in regenerated plants.

An improved and stable micropropagation system using the cytokinin, meta-Topolin (N6 (3-hydroxybenzylamino purine—mT), with nodal explants in Lagerstroemia speciosa L. was established. Among the different doses of mT, the maximum number of shoots with the highest shoot length was obtained using Murashige and Skoog’s (MS) medium supplemented with 5.0 µM mT. The results were consistent throughout the proliferation period, when recorded at week 4, 8, and 12 of being cultured, with an average of 16.4 shoots per nodal explant, and having a mean length of 4.10 cm at week 8. Shoot proliferation rates could be further improved by a combination of 5.0 µM mT with 0.5 µM α-naphthalene acetic acid in MS medium; nodal explants produced an average of 24.3 shoots with a mean length of 5.74 cm after 8 weeks of being cultured. Among the five different concentrations of three auxins tested for the rooting of microshoots in MS medium, a 1.0 µM indole-3-butyric acid treatment was the best, with an average of 10.3 roots per microshoot at an average length of 3.56 cm in 93% of microshoots within 4 weeks of being transferred to this medium. A significant reduction of both chlorophyll a and b in leaves during the first week of acclimation corresponded with a high accumulation of malondialdehyde (MDH), indicating that lipid peroxidation affected chlorophyll pigments. From the second week of acclimation, photosynthetic pigment content significantly increased and MDH content decreased. The net photosynthetic rate and leaf carotenoid content showed almost linear increases throughout the acclimation period. Activity of antioxidant enzymes, namely, superoxide dismutase, catalase, and peroxidases, consistently increased throughout the acclimation period, corresponding with the accumulation of photosynthetic pigments, thus demonstrating the role of the improved antioxidant enzymatic defense system during acclimation. A comparison of parent plant DNA with that of the greenhouse acclimated plants using random amplified polymorphic DNA and inter-simple sequence repeat markers showed a monomorphic pattern indicating genetic stability and the suitability of the method for micropropagation of L. speciosa.

Utilization of plant allelopathic potential to control weed infestations provides an effective, cost-efficient, labor-free, and environmentally acceptable alternative to traditional chemical and mechanical methods. Conocarpus erectus, known as buttonwood, belongs to the Combretaceae family with high contents of phytochemicals and antioxidant activity. There have been no studies on the allelopathic potential of C. erectus. The present study (1) examined the allelopathic potential of C. erectus against selected weeds (Chenopodium murale and Amaranthus viridis) and crops (Solanum lycopersicum and Cucumis sativus) via investigating the growth inhibition ability of its aqueous extract, and (2) identified the potential allelochemicals found in this plant. Aqueous extracts were prepared from leaves, roots, and seeds of C. erectus by immersing the dried powder of the examined plant parts in sterile distilled water for 24 h on a shaker set to 180 rpm. The resulting filtrate was considered as 100% solution, and then dilutions were made to various concentrations (75%, 50%, and 25%). C. erectus leaves and seeds showed the highest rate of inhibition at all concentrations against Chenopodium murale and Amaranthus viridis grown in either Petri dishes or pots. Conversely, all the studied extracts did not show any toxic effects against tomato and cucumber plants grown in pots. In Petri dishes, a slight reduction in growth was observed. HPLC analysis of total phenolic contents in C. erectus methanolic extracts showed that leaves have the highest contents of gallic acid, caffeic acid, and ferulic acid (153.963, 69.135, and 39.801 ppm, respectively). The finding of the current study demonstrated that the part of the plant and the concentration of extraction have a significant effect on phytotoxicity. The positive results of this study might be used to develop environmentally-friendly herbicides for agricultural purposes.

Trees are vital resources for economic, environmental, and industrial growth, supporting human life directly or indirectly through a wide variety of therapeutic compounds, commodities, and ecological services. Pterocarpus marsupium Roxb. (Fabaceae) is one of the most valuable multipurpose forest trees in India and Sri Lanka, as it is cultivated for quality wood as well as pharmaceutically bioactive compounds, especially from the stem bark and heartwood. However, propagation of the tree in natural conditions is difficult due to the low percentage of seed germination coupled with overexploitation of this species for its excellent multipurpose properties. This overexploitation has ultimately led to the inclusion of P. marsupium on the list of endangered plant species. However, recent developments in plant biotechnology may offer a solution to the overuse of such valuable species if such advances are accompanied by technology transfer in the developing world. Specifically, techniques in micropropagation, genetic manipulation, DNA barcoding, drug extraction, delivery, and targeting as well as standardization, are of substantial concern. To date, there are no comprehensive and detailed reviews of P. marsupium in terms of biotechnological research developments, specifically pharmacognosy, pharmacology, tissue culture, authentication of genuine species, and basic gene transfer studies. Thus, the present review attempts to present a comprehensive overview of the biotechnological studies centered on this species and some of the recent novel approaches for its genetic improvement.

4-Aminobiphenyl (4-ABP) and other related arylamines have emerged to be responsible for human urinary bladder tumors and cancers. Hemoglobin-ABP adducts have been recognized in the blood of smokers, and it builds up in the circulatory system over the period of years that might lead to a bladder tumor. N-hydroxy-Acetyl 4-Aminobiphenyl (N-OH-AABP) is one of the reactive forms of 4-ABP which has a potential to initiate tumor growth and causes cancer rapidly. In the present study, commercially available human DNA was modified by N-OH-AABP, and its modifications were analyzed biophysically from fluorescence spectroscopy and thermal denaturation studies. Further, Sera and IgG from bladder cancer patients’ blood were assessed for affinity to native and N-OH-AABP modified human DNA using ELISA. The study showed N-OH-AABP caused damage in the structure of the DNA macromolecule and the perturbations resulting from damage leads to change in the Tm of the DNA molecule. Bladder cancer auto-antibodies, particularly in smoker group, showed preferential binding to N-OH-AABP modified human DNA. This study shows that N-OH-AABP modified DNA could be an antigenic stimulus for the generation of autoantibodies in the sera of bladder cancer patients.

Ruta chalepensis L., an evergreen shrub in the citrus family, is well-known around the world for its essential oils and variety of bioactivities, indicating its potential medicinal applications. In this study, we investigated the effect of different culture conditions, including plant growth regulators, media types, pH of the medium, and carbon sources, on in vitro regeneration from nodal explants of R. chalepensis. Following 8 weeks of culture, the highest percentage of regeneration (96.3%) and maximum number of shoots (40.3 shoot/explant) with a length of 4.8 cm were obtained with Murashige and Skoog (MS) medium at pH 5.8, supplemented with 3.0% sucrose and 5.0 µM 6-Benzyladenine (BA) in combination with 1.0 µM 1-naphthaleneacetic acid (NAA). For rooting, individually harvested shootlets were transferred on ½ MS (half-strength) supplemented with IAA (indole-3-acetic acid), IBA (indole 3-butyric acid), or NAA, and the best response in terms of root induction (91.6%), number of roots (5.3), and root mean length (4.9 cm) was achieved with 0.5 µM IBA after 6 weeks. An average of 95.2 percent of healthy, in vitro regenerated plantlets survived after being transplanted into potting soil, indicating that they were effectively hardened. DNA assays (PCR-based markers) such as random amplification of polymorphic DNA (RAPD) and directed amplification of minisatellite-region (DAMD) were employed to assess in vitro cultivated R. chalepensis plantlets that produced a monomorphic banding pattern confirming the genetic stability. Additionally, no changes in the flow cytometric profile of ploidy between regenerated plantlets and donor plants were detected. Regeneration of this valuable medicinal plant in vitro will open up new avenues in pharmaceutical biotechnology by providing an unconventional steadfast system for mass multiplication and might be effectively used in genetic manipulation for enhanced bioactive constituents.

Diplocyclos palmatus (L.) C. Jeffrey, commonly referred to as “Shivalingi” or “Lollipop climber” is a valuable medicinal plant with a climbing growth habit used in traditional medicine. It is reputed to have antiarthritic, anti-diabetic properties and to be useful in various skin and reproductive problems. Overexploitation of wild plants and low seed germination have resulted in the decline of the species in the wild. Thus, the present investigation was aimed to establish an effective in vitro propagation procedure for its large-scale production and conservation. Nodal explants, obtained from an established mother plant were grown on MS basal medium augmented with various cytokinins, alone or in combination with auxins, to study the morphogenic response. A maximum of 8.3 shoots/explants with an average shoot length of 7.2 cm were produced after six weeks on MS containing benzylaminopurine 5.0 µM + 1-naphthaleneacetic acid 2.0 µM. After 4 weeks of transfer, microshoots rooted well on a low nutrient medium of ½ MS + 1.0 µM indole-3-butyric acid, with a maximum of 11.0 roots/microshoot and an average root length of 7.4 cm. With an 80% survival rate, the regenerated plantlets were effectively acclimatized to natural conditions. DNA-based molecular markers were used to investigate the genetic uniformity. Scanning Electron Microscopic examination of leaves indicated the adaptation of the plantlets to natural, as evidenced by the formation of normal stomata. Gas chromatography-mass spectrometry analyses of mother and micropropagated plants were performed to identify essential secondary metabolites. The results obtained show that the in vitro propagation system can be adopted for preservation, large-scale production and secondary metabolites’ production in D. palmatus.

The objective of this research was to determine the effect of zinc oxide nanoparticles (ZnONPs) and/or salicylic acid (SA) under arsenic (As) stress on rice (Oryza sativa). ZnONPs are analyzed for various techniques viz., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). All of these tests established that ZnONPs are pure with no internal defects, and can be potentially used in plant applications. Hence, we further investigated for better understanding of the underlying mechanisms and the extent of ZnONPs and SA induced oxidative stress damages. More restricted plant growth, gas exchange indices, significant reduction in the SPAD index and maximum quantum yield (Fv/Fm) and brutal decline in protein content were noticed in As-applied plants. In contrast, foliar fertigation of ZnONPs and/or SA to As-stressed rice plants lessens the oxidative stress, as exposed by subordinate levels of reactive oxygen species (ROS) synthesis. Improved enzymatic activities of catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), proline and total soluble protein contents under ZnONPs and SA treatment plays an excellent role in the regulation of various transcriptional pathways participated in oxidative stress tolerance. Higher content of nitrogen (N; 13%), phosphorus (P; 10%), potassium (K; 13%), zinc (Zn; 68%), manganese (Mn; 14%), and iron (Fe; 19) in ZnONPs and SA treated plants under As-stress, thus hampered growth and photosynthetic efficiency of rice plants. Our findings suggest that toxicity of As was conquering by the application of ZnONPs and SA in rice plants.

RNA Interference (RNAi), which works against invading nucleic acids or modulates the expression of endogenous genes, is a natural eukaryotic regulating system, and it works by noncoding smaller RNA molecules. Plant-mediated gene silencing through RNAi can be used to develop plants with insect tolerance at transcriptional or post-transcriptional levels. In this study, we selected Myzus persicae’s acetylcholinesterase 1 gene (Ace 1) as a silencing target to develop transgenic Solanum lycopersicum L. plants’ resistance to aphids. An RNAi plasmid vector containing an artificial microRNA (amiRNA) sequence was engineered and successfully transformed into Jamila and Tomaland, two elite tomato cultivars. A northern blot analysis and PCR were carried out to check the efficacy of Agrobacterium-mediated transformation in T0 transgenic plants. The quantitative PCR data showed a substantial downregulation of the Ace 1 gene in aphids fed in clip cages on T1 transgenic plants. Furthermore, there was a substantial drop in aphid colonies that were fed on T1 transgenic plants of both the cultivars. These findings strongly suggest that transgenic plants that express amiRNA could be an important tool for engineering plants resistant to aphids and possibly for the prevention of viral disease in other plant-infested pests.

Increased problems associated with side effects and bacterial resistance of chemical drugs has prompted the research focus on herbal medicines in the past few decades. In the present investigation, the antimicrobial activity of the various parts of Avicennia marina (AM), a mangrove plant, has been evaluated. The plants were collected from the Jazan area of the Kingdom of Saudi Arabia. Primary extracts of roots, stem, leaves, fruits, and seeds were made in ethanol and fractioned in ethanol, ethyl acetate, petroleum ether, chloroform, and water. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the extracts were determined against Bacillussubtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. It has been observed that the chloroform extract of roots of the AM exhibited inhibitory effects against both S. aureus (MIC = 1.5 ± 0.03 mg/mL) and E. coli (MIC = 1.7 ± 0.01 mg/mL). The ethanolic extract of the AM roots has shown antibacterial activity against Pseudomonas aeruginosa (MIC = 10.8 ± 0.78 mg/mL), Bacillussubtilis (MIC = 6.1 ± 0.27 mg/mL), Staphylococcus aureus (MIC = 2.3 ± 0.08 mg/mL), and Escherichia coli (MIC = 6.3 ± 0.28 mg/mL). The leaf extract of the AM in ethyl acetate showed antibacterial activity against S. aureus and E. coli. Antifungal activity of these extracts was also investigated against Aspergillus fumigatus and Candida albicans. Ethanolic extract of roots and seeds of the AM has shown antifungal activity against Aspergillus fumigatus when applied individually. Ethanolic extract of the AM fruits has shown an inhibitory effect on the growth of Aspergillus fumigatus and Candida albicans. It is suggested that the plant extracts of AM have tremendous antimicrobial activity against a group of microbes, and this effect depends on both the plant part and the solvent used for extraction. Therefore, this plant can be considered to treat various diseases caused by antibiotic-resistant bacteria.

An efficient in vitro technology has been designed for mass multiplication of Cassia occidentalis (coffee senna) through somatic embryogenesis. Genetic stability of both regenerants and mother plant was evaluated. Embryogenic calli were produced on Murashige and Skoog (MS) medium supplemented with 20.0 μM 2,4‐dichlorophenoxy acetic acid (2,4‐D). Induction of somatic embryos occurred after transfer of calli to medium with reduced concentration of 2,4‐D (10.0 μM) fortified with 1.0 μM abscisic acid (ABA). Subculturing of these embryos onto the maturation medium (1.5 μM 6‐benzyladenine + 1.0 μM ABA + 0.3 μM α‐naphthalene acetic acid) favored progression of the embryos through torpedo, heart‐shaped, and cotyledonary stages; one‐half MS medium was considered the best for conversion of cotyledonary stage embryos to young plantlets. The plantlets were acclimatized to autoclaved soil rite, after which they were transferred to the green house. Among the survived plantlets, 10 plants for each primer were randomly selected for inter‐simple sequence repeat (ISSR) analysis. Of the 10 primers tested, 5 produced reproducible and monomorphic bands, 2 led to minor variation with the appearance of unique bands, and the remaining 3 did not show any banding pattern. The majority of the regenerants had similar characteristics to the donor plant, suggesting genetic homogeneity of in vitro raised plants.

Symbiotic arbuscular mycorrhizal fungi (AMF) play a major role in plant development, growth, and relationships with the environment through a change in the accumulation of secondary metabolites; hence, we planned to investigate AMF’s influence on sennoside A and B accumulation in Senna alexandrina (SA) and Senna italica (SI). Seeds of SA (S. alexandrina free of mycorrhizae) and SI (S. italica free of mycorrhizae) were planted in two types of soils: +mycorrhiza and—mycorrhiza. The plant leaves of SA, SI, S. alexandrina with mycorrhizae (SAM) and S. italica with mycorrhizae (SIM) were collected and extracted (with 85% methanol), and sennoside A and B content was evaluated by the HPLC–UV method. The antioxidant activity of SA, SI, SAM and SIM was evaluated by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, while antimicrobial properties were evaluated by the minimum inhibitory concentration method (MIC). The AMF colonization was 85.66% and 85%, respectively, in the roots of SA and SI. The HPLC analysis showed a significant increase in (%) the content of sennoside A/sennoside B by 71.11/88.21, respectively, in SAM and 6.76/36.37 in SIM, which clearly indicated positive AMF effects. The DPPH/ABTS [The half maximal inhibitory concentration (IC50): 235.9/321.5 µg/mL] scavenging activity of SAM was comparatively higher and it also exhibited strong antibacterial action (MIC: 156.25 µg/mL), which supported the increase in sennoside content. This finding may be useful for further investigations of the symbiotic relation of mycorrhizal fungi with other plant species.

The cultivated cucumber (Cucumis sativus L.) was reported to have been developed from a wild cucumber (Cucumis hystrix Chakrav.), nevertheless, these two organisms exhibit noteworthy differences. For example, the wild cucumber is known for its high resistance to different biotic and abiotic stresses. Moreover, the leaves and fruits of the wild cucumber have a bitter taste compared to the cultivated cucumber. These differences could be attributed mainly to the differences in gene expression levels. In the present investigation, we analyzed the RNA-sequencing data to show the differentially expressed genes (DEGs) between the wild and cultivated cucumbers. The identified DEGs were further utilized for Gene Ontology (GO) and pathway enrichment analysis and for identification of transcription factors and regulators. In the results, several enriched GO terms in the biological process, cellular component, and molecular functions categories were identified and various enriched pathways, especially the biosynthesis pathways of secondary products were recognized. Plant-specific transcription factor families were differentially expressed between the wild and cultivated cucumbers. The results obtained provide preliminary evidence for the transcriptional differences between the wild and cultivated cucumbers which developed during the domestication process as a result of natural and/or artificial selection, and they formulate the basis for future genetic research and improvement of the cultivated cucumber.

An efficient method was developed for plant regeneration and establishment from alginate encapsulated synthetic seeds of Rauvolfia serpentina. Synthetic seeds were produced using in vitro proliferated microshoots upon complexation of 3% sodium alginate prepared in Llyod and McCown woody plant medium (WPM) and 100 mM calcium chloride. Re-growth ability of encapsulated nodal segments was evaluated after storage at 4 °C for 0, 1, 2, 4, 6 and 8 weeks and compared with non-encapsulated buds. Effects of different media viz; Murashige and Skoog medium; Lloyd and McCown woody Plant medium, Gamborg’s B5 medium and Schenk and Hildebrandt medium was also investigated for conversion into plantlets. The maximum frequency of conversion into plantlets from encapsulated nodal segments stored at 4 °C for 4 weeks was achieved on woody plant medium supplement with 5.0 μM BA and 1.0 μM NAA. Rooting in plantlets was achieved in half-strength Murashige and Skoog liquid medium containing 0.5 μM indole-3-acetic acid (IAA) on filter paper bridges. Plantlets obtained from stored synseeds were hardened, established successfully ex vitro and were morphologically similar to each other as well as their mother plant. The genetic fidelity of Rauvolfia clones raised from synthetic seeds following four weeks of storage at 4 °C were assessed by using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. All the RAPD and ISSR profiles from generated plantlets were monomorphic and comparable to the mother plant, which confirms the genetic stability among the clones. This synseed protocol could be useful for establishing a particular system for conservation, short-term storage and production of genetically identical and stable plants before it is released for commercial purposes.

Mangrove ecosystems are one of the habitats that host high environmental diversity at the level of physical, geomorphological and biological features in arid regions. In Saudi Arabia, mangrove ecosystems are heavily threatened by both natural hazards and human pressure. The total estimated area of mangroves in Safwa Al Khurais, Saudi Arabia, is approximately 20 000 ha in extent and comprises two species: Avicennia marina and Rhizophora mucronata. They supply detritus to the marine food web and play a significant role in the conservation of biological diversity. The main objective of this study was to analyse the demographic population sensitivity of A. marina in two representative sites on the Red Sea and the eastern coast of Saudi Arabia. A sensitivity analysis was used to assess the contributions of the inputs to the total uncertainty in the analysis outcomes. Demographic features affecting mangroves in Saudi Arabia are complex and include various aspects. The phenological phase, tree size, density, cover, number of dead trees and pneumatophore characteristics were considered in this study. A comparative analysis of Gaussian process emulators for performing a global sensitivity analysis was used to conduct a variance-based sensitivity analysis to identify which uncertain inputs drive the output uncertainty. The results showed that the interconnections between different demographic features were predictable, but that the extent of the sensitivity was uncertain. Findings from the current study are anticipated to contribute significantly towards an inclusive mangrove demographic features assessment, and towards the subsequent conservation of mangroves in Saudi Arabia. Conservation implications: The findings of the current research are discussed in light of the application of sensitivity analyses outputs in the conservation and management of mangrove ecosystems at a national level

BACKGROUND: Despite manifold benefits of nanoparticles (NPs), less information on the risks of NPs to human health and environment has been studied. Cobalt oxide nanoparticles (Co3O4-NPs) have been reported to cause toxicity in several organisms. In this study, we have investigated the role of Co3O4-NPs in inducing phytotoxicity, cellular DNA damage and apoptosis in eggplant (Solanum melongena L. cv. Violetta lunga 2). To the best of our knowledge, this is the first report on Co3O4-NPs showing phytotoxicity in eggplant. RESULTS: The data revealed that eggplant seeds treated with Co3O4-NPs for 2 h at a concentration of 1.0 mg/ml retarded root length by 81.5 % upon 7 days incubation in a moist chamber. Ultrastructural analysis by transmission electron microscopy (TEM) demonstrated the uptake and translocation of Co3O4-NPs into the cytoplasm. Intracellular presence of Co3O4-NPs triggered subcellular changes such as degeneration of mitochondrial cristae, abundance of peroxisomes and excessive vacuolization. Flow cytometric analysis of Co3O4-NPs (1.0 mg/ml) treated root protoplasts revealed 157, 282 and 178 % increase in reactive oxygen species (ROS), membrane potential (APm) and nitric oxide (NO), respectively. Besides, the esterase activity in treated protoplasts was also found compromised. About 2.4-fold greater level of DNA damage, as compared to untreated control was observed in Comet assay, and 73.2 % of Co3O4-NPs treated cells appeared apoptotic in flow cytometry based cell cycle analysis. CONCLUSION: This study demonstrate the phytotoxic potential of Co3O4-NPs in terms of reduction in seed germination, root growth, greater level of DNA and mitochondrial damage, oxidative stress and cell death in eggplant. The data generated from this study will provide a strong background to draw attention on Co3O4-NPs environmental hazards to vegetable crops.