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Background and Objective. Tibetan medicine is one of the earliest-known traditional medicines. This study aimed to evaluate the antioxidant, cytotoxic, and antibacterial potential of ethanolic extracts of nine common Tibetan formulations. Materials and Methods. An open-ended and semistructured questionnaire was used for an ethnomedicinal survey of the Tibetan formulations practiced in four Tibetan refugee settlements in Gandaki Province, Nepal. Based on the ethnomedicinal survey data, commonly used nine formulations were selected (Aru-18, Basam, Dadue, Dashel, Mutik-25, Raab Ga Yangzin Tea, Serdok-11, Sugmel-10, and Yungwa-4) to test biological activities. Antioxidant activity was evaluated using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging method. The cytotoxicity was examined by using the Allium cepa L. root tip meristem model. Similarly, the antibacterial effect was assessed by using well diffusion and broth dilution methods. Results. An ethnomedicinal survey showed a total of 52 Tibetan formulations were generally used by respondents for common diseases such as stomach disorders, diabetes, and migraine. From the antioxidant activity test, Sugmel-10 showed the highest DPPH free-radical-scavenging activity (IC50 1.8 μg/ml) and Yungwa-4 showed the lowest activity (IC50 5.2 μg/ml). Also, from the cytotoxic activity, the A. cepa root meristem model exhibited significant dose- and time-dependent growth suppression in Basam, Dadue, Mutik-25, and Serdok-11 as compared with cyclophosphamide standard drug. Similarly, Basam showed a good antibacterial effect having MIC 20 mg/ml and MBC 100 mg/ml against Enterococci faecalis. Conclusion. Research showed that Tibetan people preferred Tibetan formulations for the treatment and mitigation of several diseases. The result of antioxidant, cytotoxic, and antibacterial activities experimentally justified the ethnomedicinal value of nine common formulations (Aru-18, Basam, Dadue, Dashel, Mutik-25, Raab Ga Yangzin Tea, Serdok-11, Sugmel-10, and Yungwa-4). To the best of our knowledge, this study was performed for the first time in Nepal. Results from this preliminary study open the door to the scientific world to perform extensive pharmacological studies for designing and developing new therapeutic agents.

In flooded soils, an efficient internal aeration system is essential for root growth and plant survival. Roots of many wetland species form barriers to restrict radial O2 loss (ROL) to the rhizosphere. The formation of such barriers greatly enhances longitudinal O2 diffusion from basal parts towards the root tip, and the barrier also impedes the entry of phytotoxic compounds produced in flooded soils into the root. Nevertheless, ROL from roots is an important source of O2 for rhizosphere oxygenation and the oxidation of toxic compounds. In this paper, we review the methodological aspects for the most widely used techniques for the qualitative visualization and quantitative determination of ROL from roots. Detailed methodological approaches, practical set-ups and examples of ROL from roots with or without barriers to ROL are included. This paper provides practical knowledge relevant to several disciplines, including plant–soil interactions, biogeochemistry and eco-physiological aspects of roots and soil biota.

The hormonal signals that induce vascular differentiation are the controlling signals that synchronize plant development, organ growth regulation, and feedback cross talks between the shoot and the root. These signals regulate organ development by promoting or inhibiting plant organ growth and therefore should be clarified in order to understand the regulation of vascular differentiation. There is a continuous positive hormonal feedback communication between the shoot apices and the root tips that synchronizes plant development; each plant pole sends its growth-promoting hormonal signal to the opposite side of the plant, informing the other plant pole about its activity and quantity. The major shoot signal produced in the apical bud and young leaves is auxin, while the basic root tip signals produced in the root cap are cytokinins. Auxin promotes the initiation and development of the roots, while cytokinins from the root tips promote the development and growth of the shoot organs. Conversely, as will be clarified in this chapter, due to organ competition, identical organs may cause inhibition, when one of them becomes dominant and retards the others, a phenomenon that was termed apical dominance.

Aluminum (Al) can increase tolerance against abiotic stress, like some other beneficial elements, and provides resistance against biotic stresses. In plants, the Al tolerance mechanism is due to Al active organic acids (OA) secreted from the root tips. Depending on the plant, generally, OAs participating in the detoxification process of Al are malate, citrate, and oxalate in wheat and Arabidopsis malate, in maize citrate, and in buckwheat and tomato oxalate. The Al-activated malate transporter (ALMT) is an omnipresent family, with sequenced genomes all over the plant kingdom. The family name originated after the first identified member involved in stimulating wheat tolerance against Al. In Arabidopsis, AtALMT1 (malate channel) is significant for Al resistance expressed at the plasma membrane (PM) (epidermal cells) of the root tip. In maize, ZmALMT1 is critical for Al resistance. In Arabidopsis, NIP1;2 is a PM-localized transporter mediating Al uptake, translocation, and tolerance.

More than 4300 Eurasian elk (Alces alces) incisors, most of them pendants, were found in 84 burials in the Late Mesolithic cemetery of Yuzhniy Oleniy Ostrov, Northwest Russia. We analysed the manufacture techniques of elk teeth (4014), in the collection of the Peter the Great Museum of Anthropology and Ethnography, St Petersburg. A striking observation is that the manufacture of these pendants is similar in all burials. Teeth were worked by carving one or several grooves around the root tip. In addition to grooved ones, a number of teeth were not worked at all. The uniformity of the chosen species, tooth and techniques indicates that strict norms prevailed in the pendant industry. Despite the overall similarity, our study shows some variation in making pendants. A groove can cut the whole circumference of the root, or several distinct grooves can mark opposite sides of the root. Sometimes the grooves are deep and made carefully, and sometimes they are weak and made hastily. A typology of various groove types was created. In many graves, one groove type dominates. We interpret that this inter-burial variation and domination of one type resulted from personal choice and taste based on practicality. Such variation could also be associated with kin identifiers, but we did not find clear support for that in our study. Our study indicates that the groove types as such had no connection with particular ornaments, garments or hanging positions.

Genomic in situ hybridization (GISH) is an invaluable cytogenetic technique which enables the visualization of whole genomes in hybrids and polyploidy taxa. Total genomic DNA from one or two different species/genomes is used as a probe, labeled with a fluorochrome, and directly detected on mitotic chromosomes from root tip meristems. In sugarcane and sugarcane hybrids, we were able to characterize interspecific hybrids of two closely related species as well as intergeneric hybrids of two closely related genera.

Aluminium (Al) toxicity inhibits soybean root growth, leading to insufficient water and nutrient uptake. Two soybean lines (‘Magellan’ and PI 567731) were identified differing in Al tolerance, as determined by primary root length ratio, total root length ratio, and root tip number ratio under Al stress. Serious root necrosis was observed in PI 567731, but not in Magellan under Al stress. An F8 recombinant inbred line population derived from a cross between Magellan and PI 567731 was used to map the quantitative trait loci (QTL) for Al tolerance. Three QTL on chromosomes 3, 13, and 20, with tolerant alleles from Magellan, were identified. qAl_Gm13 and qAl_Gm20 explained large phenotypic variations (13–27%) and helped maintain root elongation and initiation under Al stress. In addition, qAl_Gm13 and qAl_Gm20 were confirmed in near-isogenic backgrounds and were identified to epistatically regulate Al tolerance via internal detoxification instead of Al3+ exclusion. Phylogenetic and pedigree analysis identified the tolerant alleles of both loci derived from the US ancestral line, A.K.[FC30761], originally from China. Our results provide novel genetic resources for breeding Al-tolerant soybean and suggest that internal detoxification contributes to soybean tolerance to excessive soil Al.

1.Ectomycorrhizal (ECM) roots are evolutionary strategies of plants for effective nutrient uptake under varying abiotic conditions. Formation and morphological differentiations of ECM roots are important strategies in foraging environments. However, little is known on how such strategies mediate the nutrients of the below- and aboveground tissues and the balances among nutrient elements across environmental gradients. 2.We studied the function of ECM symbiosis in Abies faxoniana across its distributional range in Southwest China. The effects of differential ECM strategies, i.e. the contact exploration type, the short-distance exploration type, and the medium-distance exploration type, and root tips functional traits, etc., on root and foliar N and P and N:P ratio were examined across natural environmental gradients. 3.The ECM symbionts preferentially facilitated P uptake in A. faxoniana under both N and P limitations. The uptakes of N and P were primarily promoted by the effectiveness of ECM roots, e.g. ECM root tips per unit biomass, superficial area of ECM root tips, the ratio of living and dead root tips, but negatively related to the ECM proliferations and morphological differentiations. Generally, plant N and P nutrients were always promoted by the contact exploration type, while negatively affected by the short-distance exploration type in A. faxoniana. Root and foliar N and P nutrients were expected to be affected by the medium-distance exploration type in dynamics. Especially, root P limitation could be relieved when the frequency of medium-distance exploration type up to c.15%, whilst root N limitation was strengthen when the frequency of medium-distance exploration type over 20%. 4.We suggest that both below- and above-ground nutritional traits of host tree species could be strongly affected by ECM symbiosis in natural environments. The ECM strategies responding to environmental conditions significantly affect the plant nutrient uptakes and trade-offs. ECM soil exploration types are the great supplementary mechanisms for plant nutrient uptake.

This study was carried out to determine the effects of cumin and fennel seeds extracts, on the germination, seedling development and mitotic activity in root end meristem cells of flax seed. The experiment was established in laboratory according to randomized plot factorial experiment design with three replications in incubator having 23℃ temperature. At the end of 14 days of germination period some germination parameters were measured. According to the control, it was observed that fennel extract applications positively affected the germination and seedling development of flax seed except 100 g/l dose. While germination is seen at 100 g/l, seedling growth is completely prevented. It was observed that all cumin extract applications had a negative effect on the germination and seedling development of flax seed compared to the control. This negativity has shown more effect in increasing doses. While the germination rate is gradually decreasing in increasing doses, it is observed that the growth of seedlings is completely prevented except 12.5 and 25 g/lcumin extract. Increased doses at doses other than 100 g/lincreased the mitotic index in fennel extract application and decreased the dose increase in cumin extract application. The percentage of chromosomal abnormality decreased in parallel with the increase in doses other than 100 g/l in fennel, but percentage of chromosomal abnormality increase with increasing doses in cumin extract. During mitotic examinations; mitotic abnormalities such as failure to collect the metaphase plate, bridge in anaphase and telophase were observed and their pictures were recorded., Bu çalışma kimyon ve rezene tohum ekstraktlarının keten tohumunun çimlenme, fide gelişimi ve kök ucu meristem hücreleri üzerindeki mitotik aktivitelerini belirlemek amacıyla yapılmıştır. Deney, laboratuvar koşullarında 23℃’deki inkübatörde tesadüf parsellerinde faktöriyel deneme desenine göre üç tekerrürlü olarak yapılmıştır. İki farklı öğütülmüş tohum türünden 4 farklı çözelti hazırlanmıştır. 14 günlük çimlenme süresinin sonunda, bazı çimlenme parametreleri ölçülmüştür. Kontrol uygulamasına göre, rezene ekstraktı uygulamalarının 100 g/l dozu hariç keten tohumunun çimlenme ve fide gelişimini olumlu yönde etkilediği görülmüştür. 100 g/l dozunda çimlenme görülürken, fide büyümesi tamamen engellenmiştir. Tüm kimyon ekstraktı uygulamalarının, kontrol uygulamasına kıyasla keten tohumunun çimlenme ve fide gelişimi üzerinde olumsuz bir etkisi olduğu belirlenmiştir. Bu olumsuzluk artan dozlarda daha fazla etki göstermiştir. Çimlenme oranı artan dozlarda kademeli olarak düşerken, 12.5 ve 25 g/l kimyon ekstresi hariç fidelerin büyümesinin tamamen önlendiği görülmektedir. 100 g/l dışındaki dozlar, rezene ekstraktı uygulamasında mitotik indeksi artırmış ve kimyon ekstraktı uygulamasında doz artışı mitotik indeksi azaltmıştır. Kromozomal anormallik yüzdesi, rezenelerde 100 g/l dışındaki dozlardaki artışa paralel olarak azalmış, ancak kimyon ekstraktında artan dozlarla kromozomal anormallik yüzdesi artmıştır. Mitotik incelemelerde; metafaz plağında toplanamama, anafazda ve telofazda köprü gibi mitotik anormallikler gözlenmiş ve resimleri kaydedilmiştir. Tüm bu bilgiler ışığında, rezene ekstraktının keten tohumunda çimlenmeyi teşvik ettiği görülmüştür. Bu etkinin, yapılacak daha ayrıntılı çalışmalar sayesinde farklı tohumlardaki dormansiyi kırmak için kullanılabileceği düşünülmektedir. Bunun yanında kimyon ekstraktının bazı tohumlarda çimlenmeyi önlemek üzere kullanılabileceği değerlendirilmektedir.

Exogenous low pH stress causes cell death in root cells, limiting root development, and agricultural production. Different lines of evidence suggested a relationship with cell wall (CW) remodeling players. We investigated whether class III peroxidase (CIII Prx) total activity, CIII Prx candidate gene expression, and reactive oxygen species (ROS) could modify CW structure during low pH-induced cell death in Arabidopsis thaliana roots. Wild-type roots displayed a good spatio-temporal correlation between the low pH-induced cell death and total CIII Prx activity in the early elongation (EZs), transition (TZs), and meristematic (MZs) zones. In situ mRNA hybridization showed that AtPrx62 transcripts accumulated only in roots treated at pH 4.6 in the same zones where cell death was induced. Furthermore, roots of the atprx62-1 knockout mutant showed decreased cell mortality under low pH compared to wild-type roots. Among the ROS, there was a drastic decrease in O2●− levels in the MZs of wild-type and atprx62-1 roots upon low pH stress. Together, our data demonstrate that AtPrx62 expression is induced by low pH and that the produced protein could positively regulate cell death. Whether the decrease in O2●− level is related to cell death induced upon low pH treatment remains to be elucidated.

Auxin is a key signal regulating plant growth and development. It is well established that auxin dynamics depend on the spatial distribution of efflux and influx carriers on the cell membranes. In this study, we employ a systems approach to characterise an alternative symplastic pathway for auxin mobilisation via plasmodesmata, which function as intercellular pores linking the cytoplasm of adjacent cells. To investigate the role of plasmodesmata in auxin patterning, we developed a multicellular model of the Arabidopsis root tip. We tested the model predictions using the DII-VENUS auxin response reporter, comparing the predicted and observed DII-VENUS distributions using genetic and chemical perturbations designed to affect both carrier-mediated and plasmodesmatal auxin fluxes. The model revealed that carrier-mediated transport alone cannot explain the experimentally determined auxin distribution in the root tip. In contrast, a composite model that incorporates both carrier-mediated and plasmodesmatal auxin fluxes re-capitulates the root-tip auxin distribution. We found that auxin fluxes through plasmodesmata enable auxin reflux and increase total root-tip auxin. We conclude that auxin fluxes through plasmodesmata modify the auxin distribution created by efflux and influx carriers., Highlighted Article: A multicellular model of auxin transport in the Arabidopsis root tip reveals the importance of intercellular plasmodesmata in maintaining auxin pattern and fluxes.

Boron (B) is an essential plant micronutrient. Deficiencies of B have drastic consequences on plant development leading to crop yield losses and reductions in root and shoot growth. Understanding the molecular and cellular consequences of B deficiency is challenging, partly because of the limited availability of B imaging techniques. In this report we demonstrate the efficacy of using 4-fluorophenylboronic acid (FPBA) as a B imaging agent, which is a derivative of the B deficiency mimic phenylboronic acid (PBA). We show that radioactively labelled [18F]FPBA (t½=110 m) accumulates at the root tip, the root elongation zone and at lateral root initiation sites in maize roots, and also translocates to the shoot where it accumulates along the leaf edges. Treatment of maize seedlings using FPBA and PBA causes a shortened primary root phenotype with absence of lateral roots in a dose-dependent manner. The primary root defects can be partially rescued by the addition of boric acid indicating that PBA can be used to induce B deficiency in maize and that radioactively labelled FPBA can be used to image sites of B demand on a tissue level.

Genetic variation in the tissue strength of sugar beet (Beta vulgaris L.) roots has been found in recent studies. There are indications that tissue strength influences damage susceptibility and storability. The objective of this study was to analyse the impact of storage on tissue strength, to determine causes for differences in tissue strength and to find possible relations between tissue strength, damage susceptibility and storability of sugar beet genotypes. For this purpose, trials with six sugar beet genotypes were conducted in seven environments across Germany in 2018 and 2019, followed by a screening trial with 12 commercial genotypes at one location in 2020. Tissue strength changed during storage depending on the growing environment, but independently of the genotype; puncture resistance increased by 0.35 MPa. The genotypic tissue strength was mainly determined by the cell wall content (r² up to 0.97), less by the cell wall composition. For sugar beet genotypes, the relationship between tissue strength and storability could be explained by the fact that root tip breakage and subsequent storage losses tended to decrease with higher tissue strength, as shown by principal component analysis (PCA). Introducing tissue strength as a variety trait in breeding and official variety trials could thus contribute to reduced harvest and storage losses in the future.

Differences in the storability of sugar beet genotypes have been reported to be related to the marc content of beets. Hence, this study aimed at identifying 1) general patterns to characterize varieties and growing sites for low storage losses, 2) the causal relationship between marc content of varieties and their damage susceptibility, infestation with mould and rots and sugar losses after storage, and 3) the environmental stability of the marc content of varieties. For the storage experiments, 10 varieties were grown at 8 sites in Germany, the Netherlands, Belgium and Sweden in 2015, 2016. After harvest, roots were stored for 8 weeks under controlled conditions. To evaluate the environmental stability, the same 10 varieties were grown at 12 sites in D, NL, B, S and Moldova in 2015 and 11 sites in D, NL, B, S in 2016. The results demonstrate a marked effect of the site on the extent of root tip breakage and surface damages, on infestation with mould and rots and on storage losses (invert sugar content, sugar losses). A general pattern could be identified: in most cases, a higher marc content of varieties coincided with less damages and less infestation with mould and rots, resulting in lower sugar losses. With the exception of variety 1, the marc content provided an indication of the storability of the varieties. The marc content turned out to be a very stable variety trait. These results indicate possibilities for breeding and selection for higher marc content and presumed better storability.

Lentil is now an integral part of prairie cropping systems. Climate forecasts point to variable and increased drought frequency, putting lentil production in jeopardy. Future lentil genotypes will require root systems that can extract more water under drought conditions. This study focuses on root diameter and root tip number, traits known to play an important role in water uptake during drought. We compared the total root length (TRL) in three soil horizons of both wild and cultivated lentil genotypes for three root diameter classes when plants were grown under moderate or severe drought, and when re-watered after exposure to moderate drought conditions. Our study demonstrates that roots of both wild and cultivated lentil genotypes can be categorized into very fine, fine and small diameter classes. Some wild lentil genotypes had significantly higher TRL in the B and C soil horizons when grown under severe or moderate drought and therefore, could act as resources for the transfer of root traits to cultivated lentil genotypes. Further evaluations focused on the root systems of interspecific recombinant inbred lines under drought conditions will be required to determine whether these traits are heritable.

Dry seeding is a resource-saving rice establishment method. With an equivalent yield, dry seeded flooded rice (DSR) has been considered as a replacement for traditional transplanted flooded rice (TFR). However, the differences in leaf and root senescence during grain filling between DSR and TFR were seldom identified. In this study, the root length, root tip number and leaf senescence of rice varieties Huanghuazhan and Yangliangyou 6 during ripening were compared between DSR and TFR. Results showed that top three leaves in DSR had the characteristics of relatively lower SPAD value, lower N content and premature leaf senescence. In addition, both the total root length and total root tip number of DSR were significantly lower than those of TFR. In conclusion, premature and quick leaf senescence was related with inadequate root length and root tip number during ripening, which might result from the deficiency of nitrogen supply in DSR. Techniques on improving leaf nitrogen status and delaying the leaf senescence during grain-filling in DSR should be developed in future researches. Keywords: dry seeded rice, transplanted flooded rice, SPAD value, leaf senescence, root length, root tip number

The present study evaluates the cytogenetic effects of both silver and gold nanoparticles on the root cells of Allium cepa. In this study, the root cells of Allium cepa were treated with both gold and silver nanoparticles of different concentrations (1 mg/L, 5 mg/L and 10 mg/L) along with control for 72 h. Experimental results revealed that after 72 h of exposure, a significant decrease in mitotic index (MI) from 68% (control) to 52.4% (1 mg/L), 47.3% (5 mg/L) and 41.4% (10 mg/L) for gold nanoparticles and 57.1% (1 mg/L), 53% (5 mg/l), 55.8% (10 mg/L) for silver nanoparticles. Through minute observation of the photograph, it was recorded that some specific chromosomal abnormalities such as stickiness of chromosome, chromosome breaks, nuclear notch, and clumped chromosome at different exposure conditions. Therefore, present results clearly suggest that Allium cepa root tip assay could be a viable path through which negative impact of both gold and silver nanoparticles can be demonstrated over a wide range of concentrations. Keywords: Allium cepa, Gold nanoparticles, Silver nanoparticles, Mitotic index, Chromosomal aberrations

Autotransplantation is considered a standard procedure with a poorer prognosis for mature than for immature teeth. In this case report, the root tip of an almost fully developed tooth was resected during autotransplantation to fit into a deficient recipient site. As a positive side effect, the apical foramen was enlarged, with potential improvement of the probability of revascularization. Clinical and radiologic follow-up examinations up to 18 months indicated revascularization and uneventful periodontal regeneration and thus successful autotransplantation. This case supports the hypothesis that intraoperative apicoectomy can improve the prognosis for revascularization of mature autotransplanted teeth. Further prospective controlled clinical studies are needed to confirm this innovative surgical approach.

Phosphorous (P) deficiency induces root cortical aerenchyma (RCA) formation in Chinese fir seedlings with marked genotypic variation, and the adaptive role of RCA is mainly related to root P reduction. Root cortical aerenchyma (RCA) formation in response to phosphorus (P) deficiency and its adaptive role are largely unexplored in trees. We hypothesized that RCA formation in response to P deficiency varies with its severity and genotype, and that P-stressed seedlings maintain similar seedling growth to non-stressed seedlings by reducing the P requirements of roots and metabolic cost of soil exploration. Seedlings of two half-sib families (nos. 25 and 36) of Cunninghamia lanceolata (Chinese fir) were grown in pots with three levels of P supply for 3 months. Significant differences in RCA formation in 40–45 mm root segments from the root tip were observed between families and P supply levels. Severe P deficiency induced more RCA formation in family no. 36 than in family no. 25, whereas moderate P deficiency induced RCA formation in family no. 36 only. Family no. 36 had significantly higher height increment, needle biomass, and P concentration in stems and needles, but lower root biomass and root P concentration, than family 25. A significantly negative relationship was found between RCA and root P concentration, increments in average root diameter, and root surface area, whereas significantly positive correlations were observed between some root morphological traits and biomass and P concentration in the organs of P-stressed seedlings of family 36. In conclusion, severe P deficiency induces formation of RCA in Chinese fir seedlings with marked genotypic variation, and the adaptive role of RCA formation during P deficiency is mainly related to the reduction of root P concentration.

The harmful potential of the Colorado potato beetle (Leptinotarsa decemlineata (Say)), and its resistance to many insecticides in current use have drawn the attention of specialists across the worl...

Exposure of barley roots to mM concentrations of L-NAME for 30 min caused a considerable root growth inhibition in a dose-dependent manner. The inhibition of root growth was higher in seedlings co-treated with Cd and L-NAME, compared with roots treated with Cd alone, despite the fact that L-NAME markedly reduced the uptake of Cd by roots. Treatment of roots with L-NAME evoked a decrease in NO level in both control and Cd-treated root tips only after a relatively long lag period, which overlaps with an increase in superoxide and H2O2 levels and peroxynitrite generation. L-NAME-induced root growth inhibition is alleviated not only by the application of the NO donor SNP but also by the ROS and peroxynitrite scavengers. Our results indicate that L-NAME, a NOS inhibitor in the animal kingdom, indeed evokes NO depletion also in the plant tissues; however, it does not occur due to the action of L-NAME as an inhibitor of NOS or NOS-like activity, but as a consequence of L-NAME-induced enhanced superoxide generation, leading to increased peroxynitrite level in the root tips due to the reaction between superoxide and NO.

Due to continued industrial discharge, pollution of the aquatic system has emerged as a worldwide concern. This study was conducted to determine the possible genotoxic effect of industrial effluents (treated and untreated) by employing the Allium cepa chromosome aberrations test system. The result illustrated that the untreated effluent was more toxic compared to treated effluent, as it reduced the number of dividing cells in the root tip. All the samples of untreated effluent showed high genotoxic effect. On incrementing the dosage from 25% to 100% the gradual increasing effect was noted on A. cepa. The study states that effluent even after treatment remains genotoxic as it has the ability to initiate the chromosomal aberrations of various types.

The present investigation was undertaken to evaluate the genotoxic effect of zinc nanoparticles (ZnNPs) synthesized by leaf extract of Albizia saman on mitotic chromosomes of root tip meristematic ...

Soybean is the important crop with abundant protein, vegetable oil, and several phytochemicals. With such predominant values, soybean is cultivated with a long history. However, flooding and drought stresses exert deleterious effects on soybean growth. The present review summarizes the morphological changes and affected events in soybean exposed to such extreme-water conditions. Sensitive organ in stressed soybean at different-developmental stages is presented based on protein profiles. Protein quality control and calcium homeostasis in the endoplasmic reticulum are discussed in soybean under both stresses. In addition, the way of calcium homeostasis in mediating protein folding and energy metabolism is addressed. Finally, stress response to flooding and drought is systematically demonstrated. This review concludes the recent findings of plant response to flooding and drought stresses in soybean employed proteomic approaches. Biological significance Soybean is considered as traditional-health food because of nutritional elements and pharmacological values. Flooding and drought exert deleterious effects to soybean growth. Proteomic approaches have been employed to elucidate stress response in soybean exposed to flooding and drought stresses. In this review, stress response is presented on organ-specific manner in the early-stage plant and soybean seedling exposed to combined stresses. The endoplasmic reticulum (ER) stress is induced by both stresses; and stress-response in the ER is addressed in the root tip of early-stage soybean. Moreover, calcium-response processes in stressed plant are described in the ER and in the cytosol. Additionally, stress-dependent response was discussed in flooded and drought-stressed plant. This review depicts stress response in the sensitive organ of stressed soybean and forms the basis to develop molecular markers related to plant defense under flooding and drought stresses.

Significance Plant roots activate lateral branching in response to contact with available water, but the mechanism by which this environmental signal is perceived is poorly understood. Through a combination of empirical and mathematical-modeling approaches we discovered a central role of tissue growth in this process. Growth causes water uptake, and the biophysical changes that occur during this process are interpreted by the organism to position new lateral branches. This observation is a significant advancement in our understanding of how the environment shapes plant development and demonstrates that perception of water is intimately tied to a core biological function of the root., Water availability is a potent regulator of plant development and induces root branching through a process termed hydropatterning. Hydropatterning enables roots to position lateral branches toward regions of high water availability, such as wet soil or agar media, while preventing their emergence where water is less available, such as in air. The mechanism by which roots perceive the spatial distribution of water during hydropatterning is unknown. Using primary roots of Zea mays (maize) we reveal that developmental competence for hydropatterning is limited to the growth zone of the root tip. Past work has shown that growth generates gradients in water potential across an organ when asymmetries exist in the distribution of available water. Using mathematical modeling, we predict that substantial growth-sustained water potential gradients are also generated in the hydropatterning competent zone and that such biophysical cues inform the patterning of lateral roots. Using diverse chemical and environmental treatments we experimentally demonstrate that growth is necessary for normal hydropatterning of lateral roots. Transcriptomic characterization of the local response of tissues to a moist surface or air revealed extensive regulation of signaling and physiological pathways, some of which we show are growth-dependent. Our work supports a “sense-by-growth” mechanism governing hydropatterning, by which water availability cues are rendered interpretable through growth-sustained water movement.

Gibberellin (GA) has been shown to exert numerous beneficial physiological functions in the resistance of plant to various abiotic stresses, however, the mechanism of GA for the mitigation of Cd stress in vegetables has not been well established. This study was carried out to investigate the effect of GA on the growth and Cd uptake in lettuce plants. Result showed that 10 µmol/L GA treatment restored part of the root morphology and vigor of lettuce under Cd stress by increasing the total root length, surface area and total root tip number, which directly showed an increased biomass of lettuce. On the other hand, GA reduced Cd uptake by roots and Cd root-to-shoot translocation by down-regulated expression of IRT1, Nramp1, HMA2 and HMA4, which finally alleviated the toxic effects of Cd on lettuce leaves, as confirmed by Non-invasive micro-test Technique (NMT) results. Overall, these findings provide new insights into the mechanism of cadmium toxicity mitigation in vegetables by GA and provide a theoretical basis for the development of physiological blockers with gibberellin components.