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In plants, light quality plays significant roles in photomorphogenesis and photosynthesis. Efficient in vitro plant propagation techniques involve tailoring of various environmental cues and culture media according to the plant species. Plant tissue culture consists of several applications in scientific research, agriculture, biotechnology, and commercial industrial purposes. Utilization of light to enhance the quality of the in vitro raised plants have been evidenced by numerous researchers in plant tissue culture. The advent of light-emitting diode- (LED-) based artificial lighting systems in plant tissue culture for micropropagation has enhanced callus induction, shoot and root organogenesis, and acclimatization of in vitro propagated plants. Plants tend to perceive the light spectra present in the photosynthetically active region (PAR) ranging from 400 to 700 nm; this includes blue and red light wavelengths. Although the influence of spectral quality is being investigated in diverse plant species, particularly, its importance in in vitro propagated horticultural crops is gaining notable interest among researchers. In recent days, the application of LEDs provides better amenability according to the plant species of interest for efficient plant regeneration. Considering the growing necessity and emerging applications of LED supplemental lights for propagation of plants in in vitro, the present review summarizes the outcomes of various research studies dealing with LEDs in plant tissue culture. Moreover, the present endeavor has provided a comprehensive overview on the effects of LEDs in the morphogenesis of plants cultured in vitro.

The genus Fragaria encompass fruits with diverse colors influenced by the distribution and accumulation of anthocyanin. Particularly, the fruit colors of strawberries with different ploidy levels are determined by expression and natural variations in the vital structural and regulatory genes involved in the anthocyanin pathway. Among the regulatory genes, MYB10 transcription factor is crucial for the expression of structural genes in the anthocyanin pathway. In the present study, we performed a genome wide investigation of MYB10 in the diploid and octoploid Fragaria species. Further, we identified seven quantitative trait loci (QTLs) associated with fruit color in octoploid strawberry. In addition, we predicted 20 candidate genes primarily influencing the fruit color based on the QTL results and transcriptome analysis of fruit skin and flesh tissues of light pink, red, and dark red strawberries. Moreover, the computational and transcriptome analysis of MYB10 in octoploid strawberry suggests that the difference in fruit colors could be predominantly influenced by the expression of MYB10 from the F. iinumae subgenome. The outcomes of the present endeavor will provide a platform for the understanding and tailoring of anthocyanin pathway in strawberry for the production of fruits with aesthetic colors.

The genus Fragaria encompass fruits with diverse colors influenced by the distribution and accumulation of anthocyanin. Particularly, the fruit colors of strawberries with different ploidy levels are determined by expression and natural variations in the vital structural and regulatory genes involved in the anthocyanin pathway. Among the regulatory genes, MYB10 transcription factor is crucial for the expression of structural genes in the anthocyanin pathway. In the present study, we performed a genome wide investigation of MYB10 in the diploid and octoploid Fragaria species. Further, we identified seven quantitative trait loci (QTLs) associated with fruit color in octoploid strawberry. In addition, we predicted 20 candidate genes primarily influencing the fruit color based on the QTL results and transcriptome analysis of fruit skin and flesh tissues of light pink, red, and dark red strawberries. Moreover, the computational and transcriptome analysis of MYB10 in octoploid strawberry suggests that the difference in fruit colors could be predominantly influenced by the expression of MYB10 from the F. iinumae subgenome. The outcomes of the present endeavor will provide a platform for the understanding and tailoring of anthocyanin pathway in strawberry for the production of fruits with aesthetic colors.

Strawberry is an allo-octoploid crop with high genome heterozygosity and complexity, which hinders the sequencing and the assembly of the genome. However, in the present study, we have generated a chromosome level assembly of octoploid strawberry sourced from a highly homozygous inbred line ‘Wongyo 3115’, using long- and short-read sequencing technologies. The assembly of ‘Wongyo 3115’ produced 805.6 Mb of the genome with 323 contigs scaffolded into 208 scaffolds with an N50 of 27.3 Mb after further gap filling. The whole genome annotation resulted in 151,892 genes with a gene density of 188.52 (genes/Mb) and validation of a genome, using BUSCO analysis resulted in 94.10% complete BUSCOs. Firmness is one of the vital traits in strawberry, which facilitate the postharvest shelf-life qualities. The molecular and genetic mechanisms that contribute the firmness in strawberry remain unclear. We have constructed a high-density genetic map based on the ‘Wongyo 3115’ reference genome to identify loci associated with firmness in the present study. For the quantitative trait locus (QTL) identification, the ‘BS F2’ populations developed from two inbred lines were genotyped, using an Axiom 35K strawberry chip, and marker positions were analyzed based on the ‘Wongyo 3115’ genome. Genetic maps were constructed with 1,049 bin markers, spanning the 3,861 cM. Using firmness data of ‘BS F2’ obtained from 2 consecutive years, five QTLs were identified on chromosomes 3-3, 5-1, 6-1, and 6-4. Furthermore, we predicted the candidate genes associated with firmness in strawberries by utilizing transcriptome data and QTL information. Overall, we present the chromosome-level assembly and annotation of a homozygous octoploid strawberry inbred line and a linkage map constructed to identify QTLs associated with fruit firmness.

Addressing the deterioration effects due to chlorine salt use as an anti-freezing agent to prevent the deposition of ice on roads during heavy snowfall is a serious issue to protect the ecosystem. Therefore, the present study was conducted to determine the effects caused by deicing agents on three different creeper plant species that commonly grow on roadsides, such as Trachelospermum asiaticum, Euonymus fortunei, and Gelsemium sempervirens. The two chlorine salts calcium chloride (CaCl2) and magnesium chloride (MgCl2) were applied to plants either as a splash or spray in different concentrations at different intervals. After 6 days of treatments, the results suggested that application of both CaCl2 and MgCl2 affected the chlorophyll content and physiological processes of the creepers in a dose-dependent manner. Further analysis of oxidative stress related parameters such as lipid peroxidation, superoxide, and hydrogen peroxide content showed that both CaCl2 and MgCl2 affected redox homeostasis. While the application of deicing agents induced the activities of antioxidant enzymes, they also decreased the content of ascorbate and proline, which are efficient osmolytes, in the dose-dependent manner. Nevertheless, comparatively oxidative stress induced by CaCl2 is higher than the MgCl2 in all three creeper-type plants included in our analysis; still the frequent application and higher concentration of both deicing agents interrupt the growth of roadside vegetation. Despite the relative toxicity of the deicers, T. asiaticum was affected lesser than E. fortunei and G. sempervirens.

Powdery mildew (PM) is a common fungal disease infecting pepper plants worldwide. Molecular breeding of pepper cultivars with powdery mildew resistance is desirable for the economic improvement of pepper cultivation. In the present study, 188 F5 population derived from AR1 (PM resistant) and TF68 (PM sensitive) parents were subjected to high-throughput genotyping by sequencing (GBS) for the identification of single nucleotide polymorphism (SNP) markers. Further, the identified SNP markers were utilized for the construction of genetic linkage map and QTL analysis. Overall read mapping percentage of 87.29% was achieved in this study with the total length of mapped region ranging from 2,956,730 to 25,537,525 bp. A total of 41,111 polymorphic SNPs were identified, and a final of 1,841 SNPs were filtered for the construction of a linkage map. A total of 12 linkage groups were constructed corresponding to each chromosome with 1,308 SNP markers with the map length of 2506.8 cM. Further, two QTLs such as Pm-2.1 and Pm-5.1 were identified in chromosomes 2 and 5, respectively, for the PM resistance. Overall, the outcomes of the present endeavor can be utilized for the marker-assisted selection of pepper with powdery mildew-resistant trait.

Watermelon (Citrulus lantus) is an important horticultural crop which belongs to the Curcubitaceae family. The nutraceutical potential of watermelon has been illustrated by several researchers, which makes it a better choice of functional food. Watermelon has been used to treat various ailments, such as cardio-vascular diseases, aging related ailments, obesity, diabetes, ulcers, and various types of cancers. The medicinal properties of watermelon are attributed by the presence of important phytochemicals with pharmaceutical values such as lycopene, citrulline, and other polyphenolic compounds. Watermelon acts as vital source of l-citrulline, a neutral-alpha amino acid which is the precursor of l-arginine, an essential amino acid necessary for protein synthesis. Supplementation of l-citrulline and lycopene displayed numerous health benefits in in vitro and in vivo studies. Similarly, the dietary intake of watermelon has proven benefits as functional food in humans for weight management. Apart from the fruits, the extracts prepared from the seeds, sprouts, and leaves also evidenced medicinal properties. The present review provides a comprehensive overview of benefits of watermelon for the treatment of various ailments.

A hydroponic cultivation system was established to improve the nutraceutical properties of Ligularia fischeri (Ledeb.) Turcz, during which nutrient uptake by the plant from nutrient solution was measured using inductive coupled plasma-atomic emission spectroscopy (ICP-AES). Based on the obtained data, the uptake of macro and micro elements per gram of fresh weight was calculated. The uptake of macro-elements of NH4+-N, NO3−-N, K, S, P, Ca, and Mg were 1.62, 4.27, 8.41, 1.19, 2.59, 2.79, and 0.84 mg·g−1 FW and micro-elements of B, Fe, Mn, Mo, Cu, and Zn were 9.91, 22.31, 25.73, 2.51, 2.91, and 5.07 µg·g−1 FW. Moreover, the effects of cultivation systems on growth and phytochemical composition of L. fischeri were compared. The greatest biomass was observed in the hydroponic cultivation system with continuous circulation nutrient solution compared to natural soil and Tosilee media based culture systems. The recirculated hydroponic system significantly increased the total phenol contents of the leaf, petiole, and root extracts by 17.6%, 30.6%, and 20.9% more compared to the soil grown. The recirculated hydroponic system treatment significantly increased the total antioxidant capacity of root extracts by 55.9% more compared to the soil treatment. Based on the contents of elements, total phenolic and flavonoid, it was concluded that hydroponic cultivation system is the optimal method to enhance medicinal value. Keywords: Ligularia fischeri, hydroponic culture, micronutrient, macronutrient, phytochemical

Pepper is an economically important horticultural plant that has been widely used for its pungency and spicy taste in worldwide cuisines. Therefore, the domestication of pepper has been carried out since antiquity. Owing to meet the growing demand for pepper with high quality, organoleptic property, nutraceutical contents, and disease tolerance, genomics assisted breeding techniques can be incorporated to develop novel pepper varieties with desired traits. The application of next-generation sequencing (NGS) approaches has reformed the plant breeding technology especially in the area of molecular marker assisted breeding. The availability of genomic information aids in the deeper understanding of several molecular mechanisms behind the vital physiological processes. In addition, the NGS methods facilitate the genome-wide discovery of DNA based markers linked to key genes involved in important biological phenomenon. Among the molecular markers, single nucleotide polymorphism (SNP) indulges various benefits in comparison with other existing DNA based markers. The present review concentrates on the impact of NGS approaches in the discovery of useful SNP markers associated with pungency and disease resistance in pepper. The information provided in the current endeavor can be utilized for the betterment of pepper breeding in future.

The present endeavor has demonstrated the impacts of different sources of silicon (Si) such as potassium silicate (K2SiO3) and calcium silicate (CaSiO3) during the in vitro axillary shoot multiplication of carnation. For the Si treatments, nodal explants were cultured onto the Murashige and Skoog’s medium fortified with 1.0 mg L−1 of 6-benzyladenine and 0.5 mg L−1 indole-3-acetic acid with or without K2SiO3 and CaSiO3 in three different concentrations (0, 1.8, or 3.6 mM). After six weeks, the shoot induction ratio, number of shoots produced per explant, expression of photosystem (PS) I and II core proteins, and activities of antioxidant enzymes were examined. Among the Si sources, K2SiO3 application enhanced the axillary shoot multiplication and the uptake of Si on comparison with CaSiO3. Both forms of Si resulted in the enhancement of stomatal density, and PS-related protein such as PsaA and PsbA illustrating the apparent involvement of Si on the photosynthetic process. Nevertheless, addition of ...

Objectives: The condition monitoring was done during the machining of Stainless Steel 316 Grade using a PCB microphone with a view to related the measured Sound Signal with the nozzle wear obtained. Methods/Statistical Analysis: It is done by using a Data Acquisition Device is used to connect the Computer with the microphone to analyze the signal using LAB VIEW Software. Also a Sensor signal conditioner is attached to the microphone to boost the sound signal. The machining is done by changing the abrasive flow rate and pressure parameters and the corresponding sound signal is recorded Findings: Regression analysis was carried out using Minitab 17 software and results showed that abrasive flow rate has more influence on nozzle wear rate. Regression equations were also developed for each nozzle hour based on process parameters. Also it was observed that the nozzle exit diameter increases with increase in nozzle life time. Application/Improvements: The future aspects are to develop a generalized equation for the nozzle wear rate based on the process parameters to develop a closed loop system.

Silicon (Si) is considered one of the most beneficial elements for plant growth and development. Its advantageous effects are visible during abiotic and biotic stresses. In this experiment, the effect of Si on redox homeostasis and protein expression was studied in Rosa hybrida ‘Rock Fire.’ Acclimatized plantlets were grown hydroponically under salt stress (50 mM NaCl) for 15 days with or without 0 or 1.8 mM of potassium silicate (K2SiO3). Exposure of R. hybrida ‘Rock Fire’ to salinity restricted root growth. The addition of Si with NaCl significantly improved fresh and dry weights of roots. The presence of Si in the nutrient solution induced the growth of root hairs during both normal and stress conditions. Under salt stress, higher lipid peroxidation and excessive accumulation of reactive oxygen species (ROS) such as superoxide (O2 −) and hydrogen peroxide (H2O2) affect the redox homeostasis potential of plants. However, addition of Si decreased the content of malondialdehyde, O2 −, and H2O2. Detoxification of ROS was highly correlated with the enhanced activity and expression of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX). In addition, the two-dimensional gel electrophoresis results illustrated the improved abundance of protein on roots to overcome the salinity stress due to the addition of Si. Out of 70 spots identified, 59 proteins [except hypothetical (6%)] were functionally classified into 8 groups such as redox homeostasis/defense (15%), transcription/translation (26%), lipid metabolism (14%), signaling (13%), energy and carbohydrate metabolism (10%), transportation/metal ion-binding (7%), terpene synthesis (3%), and cell-wall regulation (6%). The observed results suggest that the substantial improvement of redox homeostasis by Si could facilitate preventive mechanism(s) to overcome the metabolic disorder emanate under salt stress.

The objective of this study was to determine the effect of light quality on the growth, physiology, and antioxidant enzyme activity of two important domestic carnation (Dianthus caryophyllus) cultivars: ‘Green Beauty’ and ‘Purple Beauty’. In vitro-grown shoot tip explants were cultured on the plant growth regulator (PGR)-free Murashige and Skoog (MS) medium under a conventional cool white fluorescent lamp (control), blue light-emitting diode (LED), or red LED. Growth traits, photosynthetic and biochemical parameters, activity of antioxidant enzymes, and nutrient content were measured after 8 weeks. Interestingly, the blue and red LED treatments resulted in a significant increase in growth, photosynthetic parameters, and nutrient content in comparison to the conventional cool white florescent lamp treatment. In addition, red LED treatment increased the activities of antioxidant enzymes and elemental contents in both cultivars. Thus, incorporating blue or red LED treatments enhances the quality of ‘Green Beauty’ and ‘Purple Beauty’ carnations propagated in vitro.

The sequencing of radish genome aids in the better understanding and tailoring of traits associated with economic importance. In order to accelerate the genomics assisted breeding and genetic selection, transcriptomes of 33 radish inbred lines with diverse traits were sequenced for the development of single nucleotide polymorphic (SNP) markers. The sequence reads ranged from 2,560,543,741 bp to 20,039,688,139 bp with the GC (%) of 47.80–49.34 and phred quality score (Q30) of 96.47–97.54%. A total of 4951 polymorphic SNPs were identified among the accessions after stringent filtering and 298 SNPs with efficient marker assisted backcross breeding (MAB) markers were generated from the polymorphic SNPs. Further, functional annotations of SNPs revealed the effects and importance of the SNPs identified in the flowering process. The SNPs were predominantly associated with the four major flowering related transcription factors such as MYB, MADS box (AG), AP2/EREB, and bHLH. In addition, SNPs in the vital flowering integrator gene (FT) and floral repressors (EMBRYONIC FLOWER 1, 2, and FRIGIDA) were identified among the radish inbred lines. Further, 50 SNPs were randomly selected from 298 SNPs and validated using Kompetitive Allele Specific PCR genotyping system (KASP) in 102 radish inbred lines. The homozygosity of the inbred lines varied from 56 to 96% and the phylogenetic analysis resulted in the clustering of inbred lines into three subgroups. Taken together, the SNP markers identified in the present study can be utilized for the discrimination, seed purity test, and adjusting parental combinations for breeding in radish.

Plant hormones and environmental factors play central roles in the regulation of growth, development, nutrient allocation, and source/sink transitions. The response and adaptation of plants are determined by complex interactions with metabolites, plant growth regulators, secondary messengers, and downstream defense and/or homeostasis genes. Plant hormones are small molecules that regulate plant growth and development, as well as responses to changing environmental conditions. Post-embryonic plant growth and development are sustained by the meristem, a source of undifferentiated cells that gives rise to the adult plant structures. The phytohormone auxin has been implicated in diverse developmental processes throughout the life cycle of plants, including apical dominance, tropic responses, vascular development, organ patterning, flower development, and fruit development. Cytokinins have the ability to induce plant cell division and were discovered in the 1950s. Salicylic acid is a phenolic compound widely distributed in plants. Plants are entrained by light intensity, spectrum, direction, and photoperiod.

Raphanus sativus (Radish) belongs to the Brassicaceae family and is a widely consumed root vegetable all around the world. The nutritional and medicinal values of radishes have been proven by several researches. Extracts prepared from the aerial and underground parts of radishes have been used in the treatment of stomach disorders, urinary infections, hepatic inflammation, cardiac disorders and ulcers in folk medicine since the ancient times. The pharmaceutical potential of radishes is attributed to the presence of its beneficial secondary metabolites, such as glucosinolates, polyphenols and isothiocyanates. The present review has focused on the impact of radish extract administration under pathological complications, such as cancer, diabetes, hepatic inflammation and oxidative stress. In addition, a comprehensive view of molecular mechanism behind the regulation of molecular drug targets associated with different types of cancers and diabetes by the bioactive compounds present in the radish extracts have been discussed in detail.

Raphanus sativus (Radish) belongs to the Brassicaceae family and is a widely consumed root vegetable all around the world. The nutritional and medicinal values of radishes have been proven by several researches. Extracts prepared from the aerial and underground parts of radishes have been used in the treatment of stomach disorders, urinary infections, hepatic inflammation, cardiac disorders and ulcers in folk medicine since the ancient times. The pharmaceutical potential of radishes is attributed to the presence of its beneficial secondary metabolites, such as glucosinolates, polyphenols and isothiocyanates. The present review has focused on the impact of radish extract administration under pathological complications, such as cancer, diabetes, hepatic inflammation and oxidative stress. In addition, a comprehensive view of molecular mechanism behind the regulation of molecular drug targets associated with different types of cancers and diabetes by the bioactive compounds present in the radish extracts have been discussed in detail.

Metabolic processes, such as photosynthesis and respiration, lead to the generation of reactive oxygen species (ROS) as a side product. Chloroplasts, mitochondria, peroxisomes, glycosomes, and plasma membranes are the predominant metabolically active cell organelles which release ROS. Plants possess enzymatic and non-enzymatic antioxidant defense systems to maintain the ROS level. Enzymatic antioxidants include superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol/glutathione peroxidase (POD), catalase (CAT), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR), aldehyde dehydrogenases (ALDH), and glutathione reductase (GR). Non-enzymatic antioxidants include ascorbate (AsA), glutathione (GSH), proline, and phenolic compounds. Under stress conditions, ROS are excessively generated in the plant. Based on the tolerance level to the salinity plants are divided into two categories: glycophytes and halophytes. Glycophytes are salt-sensitive plants and halophytes are salt-resistant plants. To adapt to the saline environment, halophytes have evolved varied anatomical features such as a salt gland or bladder, vacuolar compartmentalization, and stomata closure timing. In glycophytes under salt stress, higher lipid peroxidation, impairment of photosynthesis, osmotic stress, and ionic imbalance cause excessive generation of ROS. Perhaps higher accumulation and uncontrollable level of ROS leads to cross-reaction with other vital metabolic pathways and damages macromolecules such as lipids, proteins, and nuclei acids. Whereas in halophytes, ROS are spatial and temporal in nature. Plants with an efficient antioxidant system generally have a higher tolerance against stress. In this chapter, antioxidant defense mechanisms present in glycophytes and halophytes are described using model plants such as Arabidopsis thaliana (glycophyte) and Cakile maritima, Suaeda salsa L., and Thellungiella halophila (halophytes).

This study investigated the effect of different relative humidity (RH) regimes on graft healing of grafted seedlings of watermelon (Citrullus vulgaris Schrad.). Two watermelon cultivars (‘Speed’ and ‘Sambok Honey’) were grafted onto the ‘RS-Dongjanggun’ bottle gourd rootstock (Lagenaria siceraria Stanld.) and the grafted seedlings were maintained under one of three relative humidity regimes, 95-96% [1.1-0.8 (day) or 0.8-0.6 (night) g·m -3 vapor pressure deficit (VPD)], 97-98% [ 0.7-0.4 (day) or 0.5-0.3 (night) g·m -3 (VPD)], or 99-100% [0.3-0.0 (day) or 0.2-0.0 (night) g·m -3 (VPD)] according to the Mollier diagram based on the air temperature of 25℃ day/18℃ night with 16 h photoperiod per day. Among the RH treatments, 97-98% significantly increased plant height and fresh weight of the rootstock and scion of the ‘Speed’ and it also enhanced the graft union connection of both cultivars after two days of grafting. However, plant height and thickness of the scion of ‘Sambok Honey’ was increased by the 99-100% RH treatment. Furthermore, both cultivars grown in the 95-96 and 97-98% RH treatments consisted of lower levels of endogenous H₂O₂ and less activities of antioxidant enzymes which illustrated the occurrence of less oxidative stress. Hence, the results of this study identified the optimal RH level for the graft healing of watermelon seedlings.

A nematicidal Cry55Aa protein was expressed and purified from E. coli cells. Higher level of expression was observed in culture induced with 0.1mM of IPTG after four hours of induction. The Cry55Aa protein was purified by resuspending the crude protein in solubilizing buffer at pH 12 for 120 min. When Meloidogyne incognita was tested against different concentration of purified protein, a clear dose response lethality was observed with an LC50 value of 31.4μg/ml.

The application of grafting in tomato production has substantially improved tomato quality and yields. It has been demonstrated that humidity plays an important role in the graft healing of seedlings. This study focuses on the optimum relative humidity (RH) conditions for scion and rootstock healing of grafted tomato (Solanum lycopersicum L.) seedlings. Two tomato cultivars, ‘Super Sunload’ and ‘Super Dotaerang’, grafted onto ‘B-Blocking’ rootstock were subjected to one of three RH regimens: 70–80, 80–90, or 90–100%. The results showed that the scions of both cultivars showed apparent wilting under the 70–80 and 80–90% RH treatments. On this basis, the 90–100% RH treatment was subdivided into 95–96, 97–98, and 99–100% RH treatments, which were then applied. Among these subdivided RH treatments, the fresh weights of the scions and rootstocks significantly increased in response to the treatments of 97–98 and 99–100% RH, and the graft union connection of both cultivars was also enhanced after two days of healing. Furthermore, lower levels of endogenous H2O2 and less activity of antioxidant enzymes were observed in both cultivars in response to treatment with 95–96 or 97–98% RH, which indicated that less oxidative stress occurred. Overall, it is suggested that 97–98% is the optimal RH level for the graft healing of tomato seedlings.

This study investigated the effects of silicon (Si) nutrition on hydroponically grown Zinnia elegans under salinity stress. In this study, six treatments, the control (basal nutrients without NaCl or Si), Si 50 (1.8 mM), Si 100 (3.6 mM), NaCl 50 (50 mM), Si 50 + NaCl 50 (1.8 mM Si; 50 mM NaCl), and Si 100 + NaCl 50 (Si-3.6 mM + NaCl-50 mM), were employed. After 15 days of treatment, growth parameters, biochemical measurements, and antioxidant enzyme activities were examined. Salinity stress significantly reduced plant growth, biomass, photosynthetic parameters, and pigments, and increased the electrolyte leakage potential (ELP), lipid peroxidation, and hydrogen peroxide level. Interestingly, with Si supplementation, Z. elegans recovered from salinity stress. Si enhanced growth and photosynthesis, and prevented the decomposition of photosynthetic pigments. Moreover, the addition of Si increased membrane integrity, thereby reducing the ELP and lipid peroxidation levels under salinity stress. Furthermore, Si modulated the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX) in scavenging excess reactive oxygen species (ROS). Additionally, Si increased the macronutrient and micronutrient contents. Therefore, augmentation with Si provided salinity resistance and enhanced the growth of Z. elegans.

Although silicon (Si) is not considered as an essential element, it is beneficial to the plant growth. Its effect is more evident under abiotic and biotic stress conditions. The objective of this study is to investigate the role of Si on the in vitro growth and resistance to salt stress of Dianthus caryophyllus ‘Tula’. The experiment was designed as a factorial design with 0, 50, or 100 mg·L−1 of potassium silicate (K2SiO3) in combination with 0, 50, or 100 mM sodium chloride (NaCl). The treatment of 50 mg·L−1 Si improved the growth of plant. However, the treatment of Si at 100 mg·L−1 reduced the growth. Although NaCl retarded the growth, addition of Si along with NaCl to the culture medium mitigated the effect of NaCl. A primary defense line by Si to overcome the photosynthetic depression was apparent from the increased chlorophyll content in the Si + NaCl treatment as compared to the treatment of NaCl alone. Enhancement of growth and resistance to salinity by Si was thought to be due to the modulation in activity of antioxidant enzymes, such as superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, and catalase. Therefore, our results suggested that 50 mg·L−1 Si supplementation could be optimal for improved growth in vitro and enhanced resistance against salinity in D. caryophyllus ‘Tula’.

The objective of the current study is to determine the effect of light quality on enhancement of growth, phytochemicals, antioxidant potential, and antioxidant enzyme activities at in vitro cultures of Rehmannia glutinosa Libosch. In vitro-grown shoot tip explants were cultured on the plant growth regulator (PGR)-free Murashige and Skoog (MS) medium and cultured under a conventional cool white fluorescent light (control), blue light emitting diode (LED) light or red LED light. After four weeks, the growth traits along with total phenol content, total flavonoid content, free radical scavenging activities, and antioxidant enzyme activities were measured. Interestingly, the blue or red LED treatments showed a significant increase in growth parameters compared with the cool white florescent light. In addition, the LED treatments increased the total phenol and flavonoid levels in leaf and root extracts. Furthermore, data on the total antioxidant capacity, reducing power potential, and DPPH radical scavenging capacity also revealed the enhancement of antioxidant capacity under both blue and red LED treatments. Especially, the blue LED treatment significantly increased the antioxidant enzyme activities in both the leaf and root, followed by the red LED treatment. Modulation in the spectral quality particularly by the blue LED induced the antioxidant defense line and was directly correlated with the enhancement of phytochemicals. Therefore, the incorporation of blue or red LED light sources during in vitro propagation of R. glutinosa can be a beneficial way to increase the medicinal values of the plant.

The current study deals with in vitro propagation, antioxidant property estimation, and assessment of acacetin content inScrophularia kakudensisFranch. Adventitious shoot induction was achieved from the nodal explant with the highest number of adventitious shoots per explant (17.4) on Murashige and Skoog’s (MS) medium fortified with 2.0 mg·L−16-benzyladenine (BA) and 0.5 mg L−1indole-3-acetic acid (IAA). Maximum number of roots per plant (16.5) was noted in half strength MS medium supplemented with 0.5 mg·L−1IAA. The regenerated plants displayed successful survival ratio (95%) in the greenhouse. The highest content of acacetin, a pharmaceutically important flavonoid, was observed in the shoot extracts (in vitro: 32.83 µg·g−1FW; in vivo: 30.05 µg·g−1FW) followed by root extracts. Total phenol and flavonoid contents along with free radical scavenging assays revealed the occurrence of larger amount of antioxidants in shoot extract in comparison with callus and root extracts ofS. kakudensis. Thus, the outcome of the present study can be highly beneficial for the germplasm conservation and commercial cultivation ofS. kakudensisfor therapeutic purposes.

The present study deals with genome wide identification of single-nucleotide polymorphism (SNP) markers related to powdery mildew (PM) resistance in two pepper varieties. Capsicum baccatum (PRH1- a PM resistant line) and Capsicum annuum (Saengryeg- a PM susceptible line), were resequenced to develop SNP markers. A total of 6,213,009 and 6,840,889 SNPs for PRH1 and Saengryeg respectively have been discovered. Among the SNPs, majority were classified as homozygous type SNPs, particularly in the resistant line. Moreover, the SNPs were differentially distributed among the chromosomes in both the resistant and susceptible lines. In total, 4,887,031 polymorphic SNP loci were identified between the two lines and 306,871 high-resolution melting (HRM) marker primer sets were designed. In order to understand the SNPs associated with the vital genes involved in diseases resistance and stress associated processes, chromosome-wise gene ontology analysis was performed. The results revealed the occurrence that SNPs related to diseases resistance genes were predominantly distributed in chromosome 4. In addition, 6281 SNPs associated with 46 resistance genes were identified. Among the lines, PRH1 consisted of maximum number of polymorphic SNPs related to NBS-LRR genes. The SNP markers were validated using HRM assay in 45 F4 populations and correlated with the phenotypic disease index.

Tomato plants often grow in saline environments in Mediterranean countries where salt accumulation in the soil is a major abiotic stress that limits its productivity. However, silicon (Si) supplementation has been reported to improve tolerance against several forms of abiotic stress. The primary aim of our study was to investigate, using comparative physiological and proteomic approaches, salinity stress in chloroplasts of tomato under silicon supplementation. Tomato seedlings (Solanum lycopersicum L.) were grown in nutrient media in the presence or absence of NaCl and supplemented with silicon for 5 days. Salinity stress caused oxidative damage, followed by a decrease in silicon concentrations in the leaves of the tomato plants. However, supplementation with silicon had an overall protective effect against this stress. The major physiological parameters measured in our studies including total chlorophyll and carotenoid content were largely decreased under salinity stress, but were recovered in the presence of silicon. Insufficient levels of net-photosynthesis, transpiration and stomatal conductance were also largely improved by silicon supplementation. Proteomics analysis of chloroplasts analyzed by 2D-BN-PAGE (second-dimensional blue native polyacrylamide-gel electrophoresis) revealed a high sensitivity of multiprotein complex proteins (MCPs) such as photosystems I (PSI) and II (PSII) to the presence of saline. A significant reduction in cytochrome b6/f and the ATP-synthase complex was also alleviated by silicon during salinity stress, while the complex forms of light harvesting complex trimers and monomers (LHCs) were rapidly up-regulated. Our results suggest that silicon plays an important role in moderating damage to chloroplasts and their metabolism in saline environments. We therefore hypothesize that tomato plants have a greater capacity for tolerating saline stress through the improvement of photosynthetic metabolism and chloroplast proteome expression after silicon supplementation.

Dormancy and germination of seeds are determined by various factors such as vitality, genotype, hardness, and other environmental cues, such as moisture, air, tempera‐ ture, and light. Metabolic activity of seeds varies between the quiescent and imbibi‐ tion state. In the dry state, longevity of a seed is determined by the reactive oxygen species (ROS) such as lipid peroxyl radical (LOO•) and lipid hydroperoxide (LOOH) that are generated nonenzymatically due to lipid peroxidation (LPO). During rehydra‐ tion phase, enormous amount of ROS, such as superoxide (O2), hydrogen peroxide (H2O2) and hydroxyl (•OH) radicals, are generated from the metabolically active compartments such as mitochondria, chloroplasts, and peroxisomes. The progressive conditional, temporal, and spatial distribution of ROS is tightly controlled by the effective antioxidant system that leads to the successful germination of seeds and this phenomenon is defined as ‘oxidation window.’ Gibberellins (GAs) and abscisic acid (ABA) are the key phytohormones involved in the germination/dormancy. Former promotes germination, whereas the latter induces dormancy. Genes involved in the synthesis and signaling of GA, such as gibberellin 3-β-dioxygenase (GA3ox), GA20ox, and GA-insensitive dwarf (GID), are responsible for the conversion of GA from an inactive to a bioactive form. On the other hand, DELLA, an important protein family acting as the repressors for GA-regulating genes, is activated by ABA. Function of genes, such as SLEEPY, PICKLE, SPINDLY, SECRET AGENT, AMYLASE, GAMYB, and LEAFY, are interrelated with the GA/ABA metabolism. By inducing the ubiquitin-26S proteolysis pathway, GA overcomes the DELLA-mediated effects on germination. The E3 ubiquitin ligase SCFSLY1 (skp1-cullin-F-box-Rbx1SLY1) complex was reported to be involved in the degradation of DELLA proteins. Additionally, cell differentiation and elongation process sustained by the ROS were also linked with the ethylene, brassinosteroids, and auxins. Hence, this chapter provides the heuristic framework on the phenomenon of © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. systemic cross-talk between the ROS and phytohormones during the transition period of quiescent seeds into the metabolically active organisms.

Silicon- (Si-) induced salinity stress resistance was demonstrated at physiological and proteomic levels inCapsicum annuumfor the first time. Seedlings ofC. annuumwere hydroponically treated with NaCl (50 mM) with or without Si (1.8 mM) for 15 days. The results illustrated that saline conditions significantly reduced plant growth and biomass and photosynthetic parameters and increased the electrolyte leakage potential, lipid peroxidation, and hydrogen peroxide level. However, supplementation of Si allowed the plants to recover from salinity stress by improving their physiology and photosynthesis. During salinity stress, Si prevented oxidative damage by increasing the activities of antioxidant enzymes. Furthermore, Si supplementation recovered the nutrient imbalance that had occurred during salinity stress. Additionally, proteomic analysis by two-dimensional gel electrophoresis (2DE) followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) revealed that Si treatment upregulated the accumulation of proteins involved in several metabolic processes, particularly those associated with nucleotide binding and transferase activity. Moreover, Si modulated the expression of vital proteins involved in ubiquitin-mediated nucleosome pathway and carbohydrate metabolism. Overall, the results illustrate that Si application induced resistance against salinity stress inC. annuumby regulating the physiology, antioxidant metabolism, and protein expression.

Aldose reductase (ALR2), a vital enzyme involved in polyol pathway, has befitted as a novel drug target in antidiabetes drug discovery process. In the present study, the binding mode and pharmacokinetic properties of potential polyphenolic compounds with reported aldose reductase inhibitory activity from the genusScrophulariahave been investigated. The human ALR2 enzyme (PDB ID: 2FZD) acted as the receptor in the current study. Among the compounds investigated, acacetin, a methoxy flavonoid, displayed the stable binding to the active site of ALR2 with least binding energy value. Molecular interaction analysis revealed that acacetin interrupts the proton donation mechanism, necessary for the catalytic activity of ALR2, by forming H-bond with Tyr48 (proton donor). In addition, acacetin also possessed favorable ADME properties and complies with Lipinski’s rule of 5 representing the possible drug-like nature compared to other polyphenols. Interestingly, the biological activity predictions also ranked acacetin with higher probability score for aldose reductase inhibition activity. Moreover, the molecular dynamics simulation of ALR2-acacetin complex was validated for the stability of ligand binding and the refined complex was used for generation of receptor-ligand pharmacophore model. Thus, the molecular insights of receptor-ligand interactions gained from the present study can be utilized for the development of novel aldose reductase inhibitors fromScrophularia.