Plants

15 pages, 718 KiB

Open AccessReview

The Use of Nitrogen and Its Regulation in Cereals: Structural Genes, Transcription Factors, and the Role of miRNAs

by Diana L. Zuluaga and Gabriella Sonnante

Plants 2019, 8(8), 294; https://doi.org/10.3390/plants8080294 - 20 Aug 2019

Cited by 32 | Viewed by 4696

Cereals and, especially, rice, maize, and wheat, are essential commodities, on which human nutrition is based. Expanding population and food demand have required higher production which has been achieved by increasing fertilization, and especially nitrogen supply to cereal crops. In fact, nitrogen is [...] Read more.

Cereals and, especially, rice, maize, and wheat, are essential commodities, on which human nutrition is based. Expanding population and food demand have required higher production which has been achieved by increasing fertilization, and especially nitrogen supply to cereal crops. In fact, nitrogen is a crucial nutrient for the plant, but excessive use poses serious environmental and health issues. Therefore, increasing nitrogen use efficiency in cereals is of pivotal importance for sustainable agriculture. The main steps in the use of nitrogen are uptake and transport, reduction and assimilation, and translocation and remobilization. Many studies have been carried out on the genes involved in these phases, and on transcription factors regulating these genes. Lately, increasing attention has been paid to miRNAs responding to abiotic stress, including nutrient deficiency. Many miRNAs have been found to regulate transcription factors acting on the expression of specific genes for nitrogen uptake or remobilization. Recent studies on gene regulatory networks have also demonstrated that miRNAs can interact with several nodes in the network, functioning as key regulators in nitrogen metabolism. Full article

(This article belongs to the Special Issue Small RNAs in Crop Improvement and Breeding)

► Show Figures

Graphical abstract

19 pages, 2130 KiB

Open AccessArticle

Yield, Antioxidant Components, Oil Content, and Composition of Onion Seeds Are Influenced by Planting Time and Density

by Carmine Amalfitano, Nadezhda A. Golubkina, Laura Del Vacchio, Giuseppe Russo, Mario Cannoniero, Silvano Somma, Giuseppe Morano, Antonio Cuciniello and Gianluca Caruso

Plants 2019, 8(8), 293; https://doi.org/10.3390/plants8080293 - 20 Aug 2019

Cited by 17 | Viewed by 3547

Abstract

Research was carried out on onion landrace (Ramata di Montoro) for seed production in southern Italy, with the aim to evaluate the effects on yield and quality of four bulb planting times in factorial combination with four densities, using a split plot design [...] Read more.

Research was carried out on onion landrace (Ramata di Montoro) for seed production in southern Italy, with the aim to evaluate the effects on yield and quality of four bulb planting times in factorial combination with four densities, using a split plot design with three replicates. The number of flower stalks per plant, their height and diameter, and the inflorescence diameter decreased with the bulb planting delay and density increase. The highest plant leaf area and LAI (leaf area index), seed yield, number, and mean weight were recorded with the earliest planting time, with the lowest bulb density eliciting the highest plant leaf area but the lowest LAI and seed yield per hectare. The ratio between seeds and inflorescence weight, and seed germinability, decreased with the planting delay and density increase. Seed oil, protein, and antioxidant content (polyphenols and selenium) were highest with the last crop cycle. The polyunsaturated fatty acids, predominant in oil, increased with planting time delay, whereas the monounsaturated fatty acids decreased. Linoleic, oleic, and palmitic acid prevailed among polyunsaturated, monounsaturated, and saturated fatty acids, respectively. Planting from 20 December to 10 January with 3.3 cold-stored bulbs per m² was the most effective combination in terms of seed yield per hectare, whereas seed oil content and quality were the best, with the last crop cycle starting on 21 February, independent of bulb density. Full article

► Show Figures

Figure 1

22 pages, 2297 KiB

Open AccessEditor’s ChoiceArticle

GWAS for Starch-Related Parameters in Japonica Rice (Oryza sativa L.)

by Chiara Biselli, Andrea Volante, Francesca Desiderio, Alessandro Tondelli, Alberto Gianinetti, Franca Finocchiaro, Federica Taddei, Laura Gazza, Daniela Sgrulletta, Luigi Cattivelli and Giampiero Valè

Plants 2019, 8(8), 292; https://doi.org/10.3390/plants8080292 - 19 Aug 2019

Cited by 28 | Viewed by 6265

Abstract

Rice quality is mainly related to the following two starch components, apparent amylose content (AAC) and resistant starch (RS). The former affects grain cooking properties, while RS acts as a prebiotic. In the present study, a Genome Wide Association Scan (GWAS) was performed [...] Read more.

Rice quality is mainly related to the following two starch components, apparent amylose content (AAC) and resistant starch (RS). The former affects grain cooking properties, while RS acts as a prebiotic. In the present study, a Genome Wide Association Scan (GWAS) was performed using 115 rice japonica accessions, including tropical and temperate genotypes, with the purpose of expanding the knowledge of the genetic bases affecting RS and AAC. High phenotypic variation was recorded for the two traits, which positively correlated. Moreover, both the parameters correlated with seed length (positive correlation) and seed width (negative correlation). A correlational selection according to human preferences has been hypothesized for the two starch traits and grain size. In addition, human selection has been proposed as the causal agent even for the different phenotypes related to starch and grain size showed by the tropical and temperate japonica accessions utilized in this study. The present GWAS led to the identification of 11 associations for RS on seven chromosomes and five associations for AAC on chromosome 6. Candidate genes and co-positional relationships with quantitative trait loci (QTLs) previously identified as affecting RS and AAC were identified for 6 associations. The candidate genes and the new RS- and/or AAC-associated regions detected provide valuable sources for future functional characterizations and for breeding programs aimed at improving rice grain quality. Full article

(This article belongs to the Special Issue Cereal Breeding: Improving Seed Vigour Traits and Grain Quality)

► Show Figures

Figure 1

19 pages, 1309 KiB

Open AccessArticle

The Rooting of Stem Cuttings and the Stability of uidA Gene Expression in Generative and Vegetative Progeny of Transgenic Pear Rootstock in the Field

by Vadim Lebedev

Plants 2019, 8(8), 291; https://doi.org/10.3390/plants8080291 - 19 Aug 2019

Cited by 6 | Viewed by 5129

Abstract

Adventitious rooting plays an important role in the commercial vegetative propagation of trees. Adventitious root formation is a complex biological process, but knowledge of the possible unintended effects induced by both the integration/expression of transgenes and in vitro conditions on the rooting is [...] Read more.

Adventitious rooting plays an important role in the commercial vegetative propagation of trees. Adventitious root formation is a complex biological process, but knowledge of the possible unintended effects induced by both the integration/expression of transgenes and in vitro conditions on the rooting is limited. The long-term stability of transgene expression is important both for original transformants of woody plants and its progeny. In this study, we used field-grown pear rootstock GP217 trees transformed with the reporter ß-glucuronidase (uidA) genes with and without intron and re-transformed with the herbicide resistance bar gene as model systems. We assessed the unintended effects on rooting of pear semi-hardwood cuttings and evaluated the stability of transgene expression in progeny produced by generative (seedlings) and vegetative (grafting, cutting) means up to four years. Our investigation revealed that: (1) The single and repeated transformations of clonal pear rootstocks did not result in unintended effects on adventitious root formation in cuttings; (2) stability of the transgene expression was confirmed on both generative and vegetative progeny, and no silenced transgenic plants were detected; (3) yearly variation in the gene expressions was observed and expression levels were decreased in extremely hot and dry summer; (4) the intron enhanced the expression of uidA gene in pear plants approximately two-fold compared to gene without intron. The current study provides useful information on transgene expression in progeny of fruit trees under natural environmental conditions. Full article

(This article belongs to the Section Plant Genetics, Genomics and Biotechnology)

► Show Figures

Figure 1

21 pages, 1419 KiB

Open AccessReview

Biotechnological Potential of LSD1, EDS1, and PAD4 in the Improvement of Crops and Industrial Plants

by Maciej Jerzy Bernacki, Weronika Czarnocka, Magdalena Szechyńska-Hebda, Ron Mittler and Stanisław Karpiński

Plants 2019, 8(8), 290; https://doi.org/10.3390/plants8080290 - 16 Aug 2019

Cited by 9 | Viewed by 5702

Abstract

Lesion Simulating Disease 1 (LSD1), Enhanced Disease Susceptibility (EDS1) and Phytoalexin Deficient 4 (PAD4) were discovered a quarter century ago as regulators of programmed cell death and biotic stress responses in Arabidopsis thaliana. Recent studies have demonstrated that these proteins are also [...] Read more.

Lesion Simulating Disease 1 (LSD1), Enhanced Disease Susceptibility (EDS1) and Phytoalexin Deficient 4 (PAD4) were discovered a quarter century ago as regulators of programmed cell death and biotic stress responses in Arabidopsis thaliana. Recent studies have demonstrated that these proteins are also required for acclimation responses to various abiotic stresses, such as high light, UV radiation, drought and cold, and that their function is mediated through secondary messengers, such as salicylic acid (SA), reactive oxygen species (ROS), ethylene (ET) and other signaling molecules. Furthermore, LSD1, EDS1 and PAD4 were recently shown to be involved in the modification of cell walls, and the regulation of seed yield, biomass production and water use efficiency. The function of these proteins was not only demonstrated in model plants, such as Arabidopsis thaliana or Nicotiana benthamiana, but also in the woody plant Populus tremula x tremuloides. In addition, orthologs of LSD1, EDS1, and PAD4 were found in other plant species, including different crop species. In this review, we focus on specific LSD1, EDS1 and PAD4 features that make them potentially important for agricultural and industrial use. Full article

(This article belongs to the Special Issue ROS Responses in Plants)

► Show Figures

Figure 1

17 pages, 4682 KiB

Open AccessArticle

Selenium Accumulation, Speciation and Localization in Brazil Nuts (Bertholletia excelsa H.B.K.)

by Leonardo W. Lima, Gavin C. Stonehouse, Christina Walters, Ali F. El Mehdawi, Sirine C. Fakra and Elizabeth A. H. Pilon-Smits

Plants 2019, 8(8), 289; https://doi.org/10.3390/plants8080289 - 16 Aug 2019

Cited by 31 | Viewed by 5923

Abstract

More than a billion people worldwide may be selenium (Se) deficient, and supplementation with Se-rich Brazil nuts may be a good strategy to prevent deficiency. Since different forms of Se have different nutritional value, and Se is toxic at elevated levels, careful seed [...] Read more.

More than a billion people worldwide may be selenium (Se) deficient, and supplementation with Se-rich Brazil nuts may be a good strategy to prevent deficiency. Since different forms of Se have different nutritional value, and Se is toxic at elevated levels, careful seed characterization is important. Variation in Se concentration and correlations of this element with other nutrients were found in two batches of commercially available nuts. Selenium tissue localization and speciation were further determined. Mean Se levels were between 28 and 49 mg kg⁻¹, with up to 8-fold seed-to-seed variation (n = 13) within batches. Brazil nut Se was mainly in organic form. While present throughout the seed, Se was most concentrated in a ring 1 to 2 mm below the surface. While healthy, Brazil nuts should be consumed in moderation. Consumption of one seed (5 g) from a high-Se area meets its recommended daily allowance; the recommended serving size of 30 g may exceed the allowable daily intake (400 μg) or even its toxicity threshold (1200 μg). Based on these findings, the recommended serving size may be re-evaluated, consumers should be warned not to exceed the serving size and the seed may be sold as part of mixed nuts, to avoid excess Se intake. Full article

(This article belongs to the Special Issue Selenium Metabolism and Accumulation in Plants)

► Show Figures

Graphical abstract

24 pages, 1480 KiB

Open AccessArticle

Identification of Genes Differentially Expressed in Response to Cold in Pisum sativum Using RNA Sequencing Analyses

by Nasser Bahrman, Emilie Hascoët, Odile Jaminon, Frédéric Dépta, Jean-François Hû, Olivier Bouchez, Isabelle Lejeune-Hénaut, Bruno Delbreil and Sylvain Legrand

Plants 2019, 8(8), 288; https://doi.org/10.3390/plants8080288 - 15 Aug 2019

Cited by 16 | Viewed by 3728

Abstract

Low temperature stress affects growth and development in pea (Pisum sativum L.) and decreases yield. In this study, RNA sequencing time series analyses performed on lines, Champagne frost-tolerant and Térèse frost-sensitive, during a low temperature treatment versus a control condition, led us [...] Read more.

Low temperature stress affects growth and development in pea (Pisum sativum L.) and decreases yield. In this study, RNA sequencing time series analyses performed on lines, Champagne frost-tolerant and Térèse frost-sensitive, during a low temperature treatment versus a control condition, led us to identify 4981 differentially expressed genes. Thanks to our experimental design and statistical analyses, we were able to classify these genes into three sets. The first one was composed of 2487 genes that could be related to the constitutive differences between the two lines and were not regulated during cold treatment. The second gathered 1403 genes that could be related to the chilling response. The third set contained 1091 genes, including genes that could be related to freezing tolerance. The identification of differentially expressed genes related to cold, oxidative stress, and dehydration responses, including some transcription factors and kinases, confirmed the soundness of our analyses. In addition, we identified about one hundred genes, whose expression has not yet been linked to cold stress. Overall, our findings showed that both lines have different characteristics for their cold response (chilling response and/or freezing tolerance), as more than 90% of differentially expressed genes were specific to each of them. Full article

(This article belongs to the Section Plant Physiology and Metabolism)

► Show Figures

Figure 1

19 pages, 1320 KiB

Open AccessArticle

Integrated Use of Aureobasidium pullulans Strain CG163 and Acibenzolar-S-Methyl for Management of Bacterial Canker in Kiwifruit

by Huub de Jong, Tony Reglinski, Philip A.G. Elmer, Kirstin Wurms, Joel L. Vanneste, Lindy F. Guo and Maryam Alavi

Plants 2019, 8(8), 287; https://doi.org/10.3390/plants8080287 - 15 Aug 2019

Cited by 25 | Viewed by 4931

Abstract

An isolate of Aureobasidium pullulans (strain = CG163) and the plant defence elicitor acibenzolar-S-methyl (ASM) were investigated for their ability to control leaf spot in kiwifruit caused by Pseudomonas syringae pv. actinidiae biovar 3 (Psa). Clonal Actinidia chinensis var. deliciosa plantlets (‘Hayward’) were [...] Read more.

An isolate of Aureobasidium pullulans (strain = CG163) and the plant defence elicitor acibenzolar-S-methyl (ASM) were investigated for their ability to control leaf spot in kiwifruit caused by Pseudomonas syringae pv. actinidiae biovar 3 (Psa). Clonal Actinidia chinensis var. deliciosa plantlets (‘Hayward’) were treated with ASM, CG163 or ASM + CG163 at seven and one day before inoculation with Psa. ASM (0.2 g/L) was applied either as a root or foliar treatments and CG163 was applied as a foliar spray containing 2 × 10⁷ CFU/mL. Leaf spot incidence was significantly reduced by all treatments compared with the control. The combination of ASM + CG163 had greater efficacy (75%) than either ASM (55%) or CG163 (40%) alone. Moreover, treatment efficacy correlated positively with the expression of defence-related genes: pathogenesis-related protein 1 (PR1), β-1,3-glucosidase, Glucan endo 1,3-β-glucosidase (Gluc_PrimerH) and Class IV chitinase (ClassIV_Chit), with greater gene upregulation in plants treated with ASM + CG163 than by the individual treatments. Pathogen population studies indicated that CG163 had significant suppressive activity against epiphytic populations of Psa. Endophytic populations were reduced by ASM + CG163 but not by the individual treatments, and by 96–144 h after inoculation were significantly lower than the control. Together these data suggest that ASM + CG163 have complementary modes of action that contribute to greater control of leaf spotting than either treatment alone. Full article

(This article belongs to the Special Issue Induced Resistance (IR) of Plants)

► Show Figures

Figure 1

13 pages, 1542 KiB

Open AccessArticle

Climate, Life Form and Family Jointly Control Variation of Leaf Traits

by Hao Zhang, Zhaoxia Zeng, Zhigang Zou and Fuping Zeng

Plants 2019, 8(8), 286; https://doi.org/10.3390/plants8080286 - 14 Aug 2019

Cited by 9 | Viewed by 3154

Abstract

Variation in leaf traits may represent differences in physiological processes and environmental adaptative strategies. Using multivariate analyses, we investigated 13 leaf traits to quantify the trade-off in these traits and the trait–climate/biome relationships based on the China Plant Trait Database, which contains morphometric [...] Read more.

Variation in leaf traits may represent differences in physiological processes and environmental adaptative strategies. Using multivariate analyses, we investigated 13 leaf traits to quantify the trade-off in these traits and the trait–climate/biome relationships based on the China Plant Trait Database, which contains morphometric and physiological character information on 1215 species for 122 sites, ranging from the north to the tropics, and from deserts and grasslands to woodlands and forests. Leaf traits across the dataset of Chinese plants showed different spatial patterns along longitudinal and latitudinal gradients and high variation. There were significant positive or negative correlations among traits; however, with the exception of the leaf ¹³C:¹²C stable isotope ratio, there were no significant correlations between leaf area and other traits. Climate, life form, and family jointly accounted for 68.4% to 95.7% of trait variance. Amongst these forms of variation partitioning, the most important partitioning feature was the family independence of climate and life form (35.6% to 57.2%), while the joint effect of family and climate was 4.5% to 26.2%, and the joint effect of family and life form was 2.4% to 21.6%. The findings of this study will enhance our understanding of the variation in leaf traits in Chinese flora and the environmental adaptative strategies of plants against a background of global climate change, and also may enrich and improve the leaf economics spectrum of China. Full article

(This article belongs to the Special Issue Plants Reacts to the Changing Environment)

► Show Figures

Figure 1

11 pages, 944 KiB

Open AccessFeature PaperReview

Arabidopsis Flowers Unlocked the Mechanism of Jasmonate Signaling

by John Browse and James G. Wallis

Plants 2019, 8(8), 285; https://doi.org/10.3390/plants8080285 - 14 Aug 2019

Cited by 22 | Viewed by 5210

Abstract

The Arabidopsis male-sterile phenotype has been a wonderful model for jasmonate action in plants. It has allowed us to identify transcription factors that control gene expression during stamen and pollen maturation and provided for the discovery of the JAZ repressor proteins and the [...] Read more.

The Arabidopsis male-sterile phenotype has been a wonderful model for jasmonate action in plants. It has allowed us to identify transcription factors that control gene expression during stamen and pollen maturation and provided for the discovery of the JAZ repressor proteins and the mechanism of jasmonate signaling. More recently, it has revealed intriguing details of the spatial localization of jasmonate synthesis and perception in stamen tissues. The extensive and thoughtful application of protein–protein interaction assays to identify JAZ-interacting partners has led to a much richer appreciation of the mechanisms by which jasmonate integrates with the actions of other hormones to regulate plant growth and physiological responses. This integration is strikingly evident in stamen and pollen development in Arabidopsis, which requires the actions of many hormones. Just as importantly, it is now evident that jasmonate has very different actions during flower development and reproduction in other plant species. This integration and diversity of action indicates that many exciting discoveries remain to be made in this area of jasmonate hormone signaling and response. Full article

(This article belongs to the Special Issue The Jasmonate Pathway: New Actors, Mechanisms and Impacts)

► Show Figures

Figure 1

17 pages, 4332 KiB

Open AccessArticle

Functional Characterization of Physcomitrella patens Glycerol-3-Phosphate Acyltransferase 9 and an Increase in Seed Oil Content in Arabidopsis by Its Ectopic Expression

by Sun Ui Yang, Juyoung Kim, Hyojin Kim and Mi Chung Suh

Plants 2019, 8(8), 284; https://doi.org/10.3390/plants8080284 - 13 Aug 2019

Cited by 7 | Viewed by 4387

Abstract

Since vegetable oils (usually triacylglycerol [TAG]) are extensively used as food and raw materials, an increase in storage oil content and production of valuable polyunsaturated fatty acids (PUFAs) in transgenic plants is desirable. In this study, a gene encoding glycerol-3-phosphate acyltransferase 9 (GPAT9), [...] Read more.

Since vegetable oils (usually triacylglycerol [TAG]) are extensively used as food and raw materials, an increase in storage oil content and production of valuable polyunsaturated fatty acids (PUFAs) in transgenic plants is desirable. In this study, a gene encoding glycerol-3-phosphate acyltransferase 9 (GPAT9), which catalyzes the synthesis of lysophosphatidic acid (LPA) from a glycerol-3-phosphate and acyl-CoA, was isolated from Physcomitrella patens, which produces high levels of very-long-chain PUFAs in protonema and gametophores. P. patens GPAT9 shares approximately 50%, 60%, and 70% amino acid similarity with GPAT9 from Chlamydomonas reinhardtii, Klebsormidium nitens, and Arabidopsis thaliana, respectively. PpGPAT9 transcripts were detected in both the protonema and gametophores. Fluorescent signals from the eYFP:PpGPAT9 construct were observed in the ER of Nicotiana benthamiana leaf epidermal cells. Ectopic expression of PpGPAT9 increased the seed oil content by approximately 10% in Arabidopsis. The levels of PUFAs (18:2, 18:3, and 20:2) and saturated FAs (16:0, 18:0, and 20:0) increased by 60% and 43%, respectively, in the storage oil of the transgenic seeds when compared with the wild type. The transgenic embryos with increased oil content contained larger embryonic cells than the wild type. Thus, PpGPAT9 may be a novel genetic resource to enhance storage oil yields from oilseed crops. Full article

(This article belongs to the Special Issue Lipid Metabolism in Plants)

► Show Figures

Figure 1

12 pages, 2694 KiB

Open AccessEditor’s ChoiceArticle

Comparative and Phylogenetic Analyses of Ginger (Zingiber officinale) in the Family Zingiberaceae Based on the Complete Chloroplast Genome

by Yingxian Cui, Liping Nie, Wei Sun, Zhichao Xu, Yu Wang, Jing Yu, Jingyuan Song and Hui Yao

Plants 2019, 8(8), 283; https://doi.org/10.3390/plants8080283 - 12 Aug 2019

Cited by 50 | Viewed by 6693

Abstract

Zingiber officinale, commonly known as ginger, is an important plant of the family Zingiberaceae and is widely used as an herbal medicine and condiment. The lack of chloroplast genomic information hinders molecular research and phylogenetic analysis on ginger. We introduced the complete [...] Read more.

Zingiber officinale, commonly known as ginger, is an important plant of the family Zingiberaceae and is widely used as an herbal medicine and condiment. The lack of chloroplast genomic information hinders molecular research and phylogenetic analysis on ginger. We introduced the complete chloroplast genome of Z. officinale and identified its phylogenetic position in Zingiberaceae. The chloroplast genome of Z. officinale is 162,621 bp with a four-part circular structure and 36.1% GC content. All 113 unique genes were annotated. A total of 78 simple sequence repeats (SSRs) and 42 long repeat sequences, which are potential areas for species authentication, were found. Comparative analysis revealed some highly variable regions, including rps16-trnQ-UUG, atpH-atpI, trnT-UGU-trnL-UAA, ycf1, and psaC-ndhE. Moreover, the small single-copy (SSC) region was the most variable region in all four shared regions, indicating that it may be undergoing rapid nucleotide substitution in the family Zingiberaceae. Phylogenetic analysis based on all available chloroplasts of Zingiberales in the National Center for Biotechnology Information indicated that Zingiber is a sister branch to Kaempferia species. The availability of the Z. officinale chloroplast genome provided invaluable data for species-level authentication and phylogenetic analysis and can thus benefit further investigations on species in the family Zingiberaceae. Full article

(This article belongs to the Special Issue Plant Bioinformatics)

► Show Figures

Figure 1

12 pages, 1399 KiB

Open AccessEditor’s ChoiceArticle

Transient Heat Waves May Affect the Photosynthetic Capacity of Susceptible Wheat Genotypes Due to Insufficient Photosystem I Photoprotection

by Erik Chovancek, Marek Zivcak, Lenka Botyanszka, Pavol Hauptvogel, Xinghong Yang, Svetlana Misheva, Sajad Hussain and Marian Brestic

Plants 2019, 8(8), 282; https://doi.org/10.3390/plants8080282 - 12 Aug 2019

Cited by 49 | Viewed by 4409

Abstract

We assessed the photosynthetic responses of eight wheat varieties in conditions of a simulated heat wave in a transparent plastic tunnel for one week. We found that high temperatures (up to 38 °C at midday and above 20 °C at night) had a [...] Read more.

We assessed the photosynthetic responses of eight wheat varieties in conditions of a simulated heat wave in a transparent plastic tunnel for one week. We found that high temperatures (up to 38 °C at midday and above 20 °C at night) had a negative effect on the photosynthetic functions of the plants and provided differentiation of genotypes through sensitivity to heat. Measurements of gas exchange showed that the simulated heat wave led to a 40% decrease in photosynthetic activity on average in comparison to the control, with an unequal recovery of individual genotypes after a release from stress. Our results indicate that the ability to recover after heat stress was associated with an efficient regulation of linear electron transport and the prevention of over-reduction in the acceptor side of photosystem I. Full article

(This article belongs to the Special Issue Molecular Mechanisms and Genetics of Plant Resistance to Abiotic Stress)

► Show Figures

Figure 1

8 pages, 1837 KiB

Open AccessArticle

Investigating the Side-Effects of Neem-Derived Pesticides on Commercial Entomopathogenic and Slug-Parasitic Nematode Products Under Laboratory Conditions

by Renáta Petrikovszki, Pratik Doshi, György Turóczi, Ferenc Tóth and Péter Nagy

Plants 2019, 8(8), 281; https://doi.org/10.3390/plants8080281 - 12 Aug 2019

Cited by 8 | Viewed by 3580

Abstract

Lethal effects of neem derived pesticides (neem leaf extract (NLE) and NeemAzal-T/S (NA)) were examined on different entomopathogenic (EPN) and slug-parasitic (SPN) nematodes. In our recent study, neem derived pesticides were tested against Phasmarhabditis hermaphrodita for the first time under in vitro conditions. [...] Read more.

Lethal effects of neem derived pesticides (neem leaf extract (NLE) and NeemAzal-T/S (NA)) were examined on different entomopathogenic (EPN) and slug-parasitic (SPN) nematodes. In our recent study, neem derived pesticides were tested against Phasmarhabditis hermaphrodita for the first time under in vitro conditions. Laboratory experiments were set up in 96-well microplates with different concentrations of NLE (0.1%, 0.3%, 0.6%, and 1%) and NA (0.001%, 0.003%, 0.006%, and 0.01%) and Milli-Q water as the control. After 24-h exposure time, mortality of individual nematodes was observed and recorded. Considering LC₁₀ values, 0.1% of NLE could be used safely in combination with all the EPNs and SPNs tested in recent study. A concentration of NA three times higher than the recommended dosage did not harm either EPN or SPN species. In conclusion, NeemAzal-T/S might be applied with EPNs and the SPN Ph. hermaphrodita simultaneously, while the compatibility of neem leaf extract and beneficial nematode products needs further evaluation. Full article

► Show Figures

Figure 1

11 pages, 3193 KiB

Open AccessArticle

Bletilla striata (Orchidaceae) Seed Coat Restricts the Invasion of Fungal Hyphae at the Initial Stage of Fungal Colonization

by Chihiro Miura, Miharu Saisho, Takahiro Yagame, Masahide Yamato and Hironori Kaminaka

Plants 2019, 8(8), 280; https://doi.org/10.3390/plants8080280 - 11 Aug 2019

Cited by 7 | Viewed by 5357

Abstract

Orchids produce minute seeds that contain limited or no endosperm, and they must form an association with symbiotic fungi to obtain nutrients during germination and subsequent seedling growth under natural conditions. Orchids need to select an appropriate fungus among diverse soil fungi at [...] Read more.

Orchids produce minute seeds that contain limited or no endosperm, and they must form an association with symbiotic fungi to obtain nutrients during germination and subsequent seedling growth under natural conditions. Orchids need to select an appropriate fungus among diverse soil fungi at the germination stage. However, there is limited understanding of the process by which orchids recruit fungal associates and initiate the symbiotic interaction. This study aimed to better understand this process by focusing on the seed coat, the first point of fungal attachment. Bletilla striata seeds, some with the seed coat removed, were prepared and sown with symbiotic fungi or with pathogenic fungi. The seed coat-stripped seeds inoculated with the symbiotic fungi showed a lower germination rate than the intact seeds, and proliferated fungal hyphae were observed inside and around the stripped seeds. Inoculation with the pathogenic fungi increased the infection rate in the seed coat-stripped seeds. The pathogenic fungal hyphae were arrested at the suspensor side of the intact seeds, whereas the seed coat-stripped seeds were subjected to severe infestation. These results suggest that the seed coat restricts the invasion of fungal hyphae and protects the embryo against the attack of non-symbiotic fungi. Full article

(This article belongs to the Special Issue Contribution of Mycorrhizal Symbiosis to Plant Growth)

► Show Figures

Figure 1

13 pages, 705 KiB

Open AccessEditor’s ChoiceArticle

Comparison of Growth Rate and Nutrient Content of Five Microalgae Species Cultivated in Greenhouses

by Maria N. Metsoviti, George Papapolymerou, Ioannis T. Karapanagiotidis and Nikolaos Katsoulas

Plants 2019, 8(8), 279; https://doi.org/10.3390/plants8080279 - 10 Aug 2019

Cited by 55 | Viewed by 5452

Abstract

The effect of different environmental conditions on the growth rate, biomass production, nutrient composition, and phenolic content of the microalgae species Chlorella vulgaris, Botryococcus braunii, Chlamydomonas reinhardtii, Euglena gracilis, and Nannochloropsis oculata was investigated. The experiments were conducted in [...] Read more.

The effect of different environmental conditions on the growth rate, biomass production, nutrient composition, and phenolic content of the microalgae species Chlorella vulgaris, Botryococcus braunii, Chlamydomonas reinhardtii, Euglena gracilis, and Nannochloropsis oculata was investigated. The experiments were conducted in open bioreactors in a greenhouse in three different periods (during October, March, and June), and in a controlled environment in a closed plant growth chamber. It was found that the growth rate and production of C. vulgaris and B. braunii was higher during March, C. reinhardtii and N. oculata grew better in June, and the growth of E. gracilis was similar in March and June. The lipid content of the biomass of all five species increased with increasing light intensity and temperature, while the nitrogen free extractable (NFE) content decreased and the protein, fiber, moisture, and ash content remained relatively unaffected. The phenolic content varied from species to species with E. gracilis having the highest and N. oculata the lowest content among the species studied. The results can be taken into account when cultivating the different microalgae studied in full scale applications, such as in open raceway bioreactors, where conditions could be adjusted to obtain the most favorable growth conditions, depending on the particular species cultivated. Full article

► Show Figures

Figure 1

16 pages, 23006 KiB

Open AccessArticle

Long-Term Maintainable Somatic Embryogenesis System in Alfalfa (Medicago sativa) Using Leaf Explants: Embryogenic Sustainability Approach

by Ankush Sangra, Lubana Shahin and Sarwan K. Dhir

Plants 2019, 8(8), 278; https://doi.org/10.3390/plants8080278 - 09 Aug 2019

Cited by 6 | Viewed by 5640

Abstract

Alfalfa (Medicago sativa) is one of the most important forage legume crops because of its mass production and high feeding value. It originated in Asia and is one of the most ancient plants cultivated throughout the world as a fodder. Despite [...] Read more.

Alfalfa (Medicago sativa) is one of the most important forage legume crops because of its mass production and high feeding value. It originated in Asia and is one of the most ancient plants cultivated throughout the world as a fodder. Despite the well-studied somatic embryogenesis of alfalfa, there is a lack of a long-term maintainable somatic embryogenic system. Every time an embryogenic callus culture must be started from new explants, which is laborious, costly and time consuming. In addition to this, endogenous microorganisms present in ex vitro explants of alfalfa can often cause contamination, reducing the efficiency of callus culture. An attempt was made to establish long-term continuous somatic embryogenesis system in alfalfa using cultivar Regen-SY. Nine somatic embryogenesis pathways were studied and evaluated for embryo yield, plant conversion rate and embryogenic sustainability. Somatic embryos passed through the same stages (globular, heart-shaped, torpedo and cotyledonary) as characteristic of the zygotic embryo and secondary somatic embryogenesis was also observed. B5H-B5 system showed the highest embryo yield and plant conversion rate whereas SH4K-BOi2Y system demonstrated the highest embryogenic sustainability and maintained the embryogenic potential even after six subculture cycles. Scanning electron microscopy was applied to study the morphology of the somatic embryos and secondary somatic embryogenesis. Therefore, long-term maintainable somatic embryogenesis system protocol was developed through this study, which will help to enhance and accelerate the alfalfa biotechnology research. Full article

(This article belongs to the Section Plant Development and Morphogenesis)

► Show Figures

Figure 1

14 pages, 1988 KiB

Open AccessFeature PaperArticle

Effects of Jasmonate on Ethylene Function during the Development of Tomato Stamens

by Ramona Schubert, Stephan Grunewald, Lea von Sivers and Bettina Hause

Plants 2019, 8(8), 277; https://doi.org/10.3390/plants8080277 - 09 Aug 2019

Cited by 10 | Viewed by 3554

Abstract

The phenotype of the tomato mutant jasmonate-insensitive1-1 (jai1-1) mutated in the JA-Ile co-receptor COI1 demonstrates JA function in flower development, since it is female-sterile. In addition, jai1-1 exhibits a premature anther dehydration and pollen release, being in contrast to a delayed [...] Read more.

The phenotype of the tomato mutant jasmonate-insensitive1-1 (jai1-1) mutated in the JA-Ile co-receptor COI1 demonstrates JA function in flower development, since it is female-sterile. In addition, jai1-1 exhibits a premature anther dehydration and pollen release, being in contrast to a delayed anther dehiscence in the JA-insensitive Arabidopsis mutant coi1-1. The double mutant jai1-1 Never ripe (jai1-1 Nr), which is in addition insensitive to ethylene (ET), showed a rescue of the jai1-1 phenotype regarding pollen release. This suggests that JA inhibits a premature rise in ET to prevent premature stamen desiccation. To elucidate the interplay of JA and ET in more detail, stamen development in jai1-1 Nr was compared to wild type, jai1-1 and Nr regarding water content, pollen vitality, hormone levels, and accumulation of phenylpropanoids and transcripts encoding known JA- and ET-regulated genes. For the latter, RT-qPCR based on nanofluidic arrays was employed. The data showed that additional prominent phenotypic features of jai1-1, such as diminished water content and pollen vitality, and accumulation of phenylpropanoids were at least partially rescued by the ET-insensitivity. Hormone levels and accumulation of transcripts were not affected. The data revealed that strictly JA-regulated processes cannot be rescued by ET-insensitivity, thereby emphasizing a rather minor role of ET in JA-regulated stamen development. Full article

(This article belongs to the Special Issue The Jasmonate Pathway: New Actors, Mechanisms and Impacts)

► Show Figures

Figure 1

15 pages, 6832 KiB

Open AccessArticle

Influence of Climate on Radial Growth of Black Pine on the Mountain Regions of Southwestern Turkey

by Mehmet Doğan and Nesibe Köse

Plants 2019, 8(8), 276; https://doi.org/10.3390/plants8080276 - 09 Aug 2019

Cited by 9 | Viewed by 4035

Abstract

In this study, we identified the most important climate factors affecting the radial growth of black pine at different elevations of the mountain regions of Southwestern Turkey (Sandıras Mountain, Muğla/Turkey). We used four black pine tree-ring chronologies, which represent upper and lower distribution [...] Read more.

In this study, we identified the most important climate factors affecting the radial growth of black pine at different elevations of the mountain regions of Southwestern Turkey (Sandıras Mountain, Muğla/Turkey). We used four black pine tree-ring chronologies, which represent upper and lower distribution limits of black pine forest on the South and North slopes of Sandıras Mountain. The relationships between tree-ring width and climate were identified using response function analysis. We performed hierarchical cluster analysis to classify the response functions into meaningful groups. Black pine trees in the mountain regions of Southwestern Turkey responded positively to a warmer temperature and high precipitation at the beginning of the growing season. As high summer temperatures exacerbated drought, radial growth was affected negatively. Hierarchical cluster analysis made clear that elevation differences, rather than aspect, was the main factor responsible for the formation of the clusters. Due to the mountainous terrain of the study area, the changing climatic conditions (air temperature and precipitation) affected the tree-ring widths differently depending on elevation. Full article

(This article belongs to the Special Issue Plants Reacts to the Changing Environment)

► Show Figures

Figure 1

17 pages, 4355 KiB

Open AccessArticle

Genome-Wide Identification, Expression Pattern Analysis and Evolution of the Ces/Csl Gene Superfamily in Pineapple (Ananas comosus)

by Shijiang Cao, Han Cheng, Jiashuo Zhang, Mohammad Aslam, Maokai Yan, Anqi Hu, Lili Lin, Simon Peter Ojolo, Heming Zhao, S.V.G.N. Priyadarshani, Yuan Yu, Guangqiu Cao and Yuan Qin

Plants 2019, 8(8), 275; https://doi.org/10.3390/plants8080275 - 08 Aug 2019

Cited by 11 | Viewed by 4357

Abstract

The cellulose synthase (Ces) and cellulose synthase-like (Csl) gene families belonging to the cellulose synthase gene superfamily, are responsible for the biosynthesis of cellulose and hemicellulose of the plant cell wall, and play critical roles in plant development, growth and evolution. However, the [...] Read more.

The cellulose synthase (Ces) and cellulose synthase-like (Csl) gene families belonging to the cellulose synthase gene superfamily, are responsible for the biosynthesis of cellulose and hemicellulose of the plant cell wall, and play critical roles in plant development, growth and evolution. However, the Ces/Csl gene family remains to be characterized in pineapple, a highly valued and delicious tropical fruit. Here, we carried out genome-wide study and identified a total of seven Ces genes and 25 Csl genes in pineapple. Genomic features and phylogeny analysis of Ces/Csl genes were carried out, including phylogenetic tree, chromosomal locations, gene structures, and conserved motifs identification. In addition, we identified 32 pineapple AcoCes/Csl genes with 31 Arabidopsis AtCes/Csl genes as orthologs by the syntenic and phylogenetic approaches. Furthermore, a RNA-seq investigation exhibited the expression profile of several AcoCes/Csl genes in various tissues and multiple developmental stages. Collectively, we provided comprehensive information of the evolution and function of pineapple Ces/Csl gene superfamily, which would be useful for screening out and characterization of the putative genes responsible for tissue development in pineapple. The present study laid the foundation for future functional characterization of Ces/Csl genes in pineapple. Full article

(This article belongs to the Special Issue Genomics for Plant Breeding)

► Show Figures

Figure 1

15 pages, 3107 KiB

Open AccessArticle

Characteristics and Expression Pattern of MYC Genes in Triticum aestivum, Oryza sativa, and Brachypodium distachyon

by Shoukun Chen, Hongyan Zhao, Tengli Luo, Yue Liu, Xiaojun Nie and Haifeng Li

Plants 2019, 8(8), 274; https://doi.org/10.3390/plants8080274 - 08 Aug 2019

Cited by 24 | Viewed by 4593

Abstract

Myelocytomatosis oncogenes (MYC) transcription factors (TFs) belong to basic helix-loop-helix (bHLH) TF family and have a special bHLH_MYC_N domain in the N-terminal region. Presently, there is no detailed and systematic analysis of MYC TFs in wheat, rice, and Brachypodium distachyon. In this [...] Read more.

Myelocytomatosis oncogenes (MYC) transcription factors (TFs) belong to basic helix-loop-helix (bHLH) TF family and have a special bHLH_MYC_N domain in the N-terminal region. Presently, there is no detailed and systematic analysis of MYC TFs in wheat, rice, and Brachypodium distachyon. In this study, 26 TaMYC, 7 OsMYC, and 7 BdMYC TFs were identified and their features were characterized. Firstly, they contain a JAZ interaction domain (JID) and a putative transcriptional activation domain (TAD) in the bHLH_MYC_N region and a BhlH region in the C-terminal region. In some cases, the bHLH region is followed by a leucine zipper region; secondly, they display tissue-specific expression patterns: wheat MYC genes are mainly expressed in leaves, rice MYC genes are highly expressed in stems, and B. distachyon MYC genes are mainly expressed in inflorescences. In addition, three types of cis-elements, including plant development/growth-related, hormone-related, and abiotic stresses-related were identified in different MYC gene promoters. In combination with the previous studies, these results indicate that MYC TFs mainly function in growth and development, as well as in response to stresses. This study laid a foundation for the further functional elucidation of MYC genes. Full article

(This article belongs to the Section Plant Genetics, Genomics and Biotechnology)

► Show Figures

Figure 1

20 pages, 1385 KiB

Open AccessArticle

Morphological and Chemical Profile of Three Tomato (Solanum lycopersicum L.) Landraces of A Semi-Arid Mediterranean Environment

by Massimiliano Renna, Massimiliano D’Imperio, Maria Gonnella, Miriana Durante, Angelo Parente, Giovanni Mita, Pietro Santamaria and Francesco Serio

Plants 2019, 8(8), 273; https://doi.org/10.3390/plants8080273 - 08 Aug 2019

Cited by 14 | Viewed by 4458

Abstract

Puglia (Southern Italy), particularly rich in tomato agro-biodiversity, can be considered a typical region of the semi-arid Mediterranean environments. In this study, three local varieties of tomato (Manduria, Giallo di Crispiano and Regina) were characterized by using morphological descriptors according to international standards. [...] Read more.

Puglia (Southern Italy), particularly rich in tomato agro-biodiversity, can be considered a typical region of the semi-arid Mediterranean environments. In this study, three local varieties of tomato (Manduria, Giallo di Crispiano and Regina) were characterized by using morphological descriptors according to international standards. Chemical (isoprenoids, ascorbic acid, total phenols, sugars and mineral content) and agronomic assessment were carried out to highlight the specific traits of these local varieties well adapted to a semi-arid environment. Data of morphological traits according to the “International Union for the Protection of New Varieties of Plants” (UPOV) guideline evidenced a clear distinctness among all three landraces, especially as regards fruits. Results also highlighted that a great part of variation in chemical traits was almost exclusively due to genotypes, while in a few cases observed differences resulted from the interaction between genotype and harvest time. The results of the present study may represent the first step toward the recognition of “conservation variety” status for Regina, Giallo di Crispiano and Manduria tomato landraces. At the same time, both quality traits and agronomic performance of these tomato genotypes suggest the possibility of their cultivation in other semi-arid environments also considering their quality traits, in view of a sustainable production. Full article

(This article belongs to the Special Issue 2019 Feature Papers by Plants’ Editorial Board Members)

► Show Figures

Figure 1

51 pages, 2262 KiB

Open AccessReview

Botanicals Against Tetranychus urticae Koch Under Laboratory Conditions: A Survey of Alternatives for Controlling Pest Mites

by Ricardo A. Rincón, Daniel Rodríguez and Ericsson Coy-Barrera

Plants 2019, 8(8), 272; https://doi.org/10.3390/plants8080272 - 07 Aug 2019

Cited by 30 | Viewed by 6940

Abstract

Tetranychus urticae Koch is a phytophagous mite capable of altering the physiological processes of plants, causing damages estimated at USD$ 4500 per hectare, corresponding to approximately 30% of the total cost of pesticides used in some important crops. Several tools are used in [...] Read more.

Tetranychus urticae Koch is a phytophagous mite capable of altering the physiological processes of plants, causing damages estimated at USD$ 4500 per hectare, corresponding to approximately 30% of the total cost of pesticides used in some important crops. Several tools are used in the management of this pest, with chemical control being the most frequently exploited. Nevertheless, the use of chemically synthesized acaricides brings a number of disadvantages, such as the development of resistance by the pest, hormolygosis, incompatibility with natural predators, phytotoxicity, environmental pollution, and risks to human health. In that sense, the continuous search for botanical pesticides arises as a complementary alternative in the control of T. urticae Koch. Although a lot of information is unknown about its mechanisms of action and composition, there are multiple experiments in lab conditions that have been performed to determine the toxic effects of botanicals on this mite. Among the most studied botanical families for this purpose are plants from the Lamiaceae, the Asteraceae, the Myrtaceae, and the Apiaceae taxons. These are particularly abundant and exhibit several results at different levels; therefore, many of them can be considered as promising elements to be included into integrated pest management for controlling T. urticae. Full article

(This article belongs to the Special Issue Pesticidal Plants: From Smallholder Use to Commercialisation)

► Show Figures

Graphical abstract

14 pages, 1438 KiB

Open AccessArticle

Leaf Anatomy, Morphology and Photosynthesis of Three Tundra Shrubs after 7-Year Experimental Warming on Changbai Mountain

by Yumei Zhou, Jifeng Deng, Zhijuan Tai, Lifen Jiang, Jianqiu Han, Gelei Meng and Mai-He Li

Plants 2019, 8(8), 271; https://doi.org/10.3390/plants8080271 - 07 Aug 2019

Cited by 10 | Viewed by 4542

Abstract

Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International [...] Read more.

Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International Tundra Experiment to passively warm air and soil temperatures year round in alpine tundra. Leaf size, photosynthesis and anatomy of three dominant species were investigated during the growing seasons after 7 years of continuous warming. Warming increased the maximal light-saturated photosynthetic rate (P_max) by 43.6% for Dryas. octopetala var. asiatica and by 26.7% for Rhododendron confertissimum across the whole growing season, while warming did not significantly affect the P_max of V. uliginosum. The leaf size of Dr. octopetala var. asiatica and Rh. confertissimum was increased by warming. No marked effects of warming on anatomical traits of Dr. octopetala var. asiatica were observed. Warming decreased the leaf thickness of Rh. confertissimum and Vaccinium uliginosum. This study highlights the species-specific responses to climate warming. Our results imply that Dr. octopetala var. asiatica could be more dominant because it, mainly in terms of leaf photosynthetic capacity and size, seems to have advantages over the other two species in a warming world. Full article

(This article belongs to the Special Issue Plants Reacts to the Changing Environment)

► Show Figures

Figure 1

13 pages, 1129 KiB

Open AccessArticle

Constructing a Reference Genome in a Single Lab: The Possibility to Use Oxford Nanopore Technology

by Yun Gyeong Lee, Sang Chul Choi, Yuna Kang, Kyeong Min Kim, Chon-Sik Kang and Changsoo Kim

Plants 2019, 8(8), 270; https://doi.org/10.3390/plants8080270 - 06 Aug 2019

Cited by 10 | Viewed by 5349

Abstract

The whole genome sequencing (WGS) has become a crucial tool in understanding genome structure and genetic variation. The MinION sequencing of Oxford Nanopore Technologies (ONT) is an excellent approach for performing WGS and it has advantages in comparison with other Next-Generation Sequencing (NGS): [...] Read more.

The whole genome sequencing (WGS) has become a crucial tool in understanding genome structure and genetic variation. The MinION sequencing of Oxford Nanopore Technologies (ONT) is an excellent approach for performing WGS and it has advantages in comparison with other Next-Generation Sequencing (NGS): It is relatively inexpensive, portable, has simple library preparation, can be monitored in real-time, and has no theoretical limits on reading length. Sorghum bicolor (L.) Moench is diploid (2n = 2x = 20) with a genome size of about 730 Mb, and its genome sequence information is released in the Phytozome database. Therefore, sorghum can be used as a good reference. However, plant species have complex and large genomes when compared to animals or microorganisms. As a result, complete genome sequencing is difficult for plant species. MinION sequencing that produces long-reads can be an excellent tool for overcoming the weak assembly of short-reads generated from NGS by minimizing the generation of gaps or covering the repetitive sequence that appears on the plant genome. Here, we conducted the genome sequencing for S. bicolor cv. BTx623 while using the MinION platform and obtained 895,678 reads and 17.9 gigabytes (Gb) (ca. 25× coverage of reference) from long-read sequence data. A total of 6124 contigs (covering 45.9%) were generated from Canu, and a total of 2661 contigs (covering 50%) were generated from Minimap and Miniasm with a Racon through a de novo assembly using two different tools and mapped assembled contigs against the sorghum reference genome. Our results provide an optimal series of long-read sequencing analysis for plant species while using the MinION platform and a clue to determine the total sequencing scale for optimal coverage that is based on various genome sizes. Full article

(This article belongs to the Special Issue Plant Bioinformatics)

► Show Figures

Figure 1

11 pages, 2121 KiB

Open AccessCommunication

Effect of Thermospermine on the Growth and Expression of Polyamine-Related Genes in Rice Seedlings

by Minaho Miyamoto, Satoshi Shimao, Wurina Tong, Hiroyasu Motose and Taku Takahashi

Plants 2019, 8(8), 269; https://doi.org/10.3390/plants8080269 - 06 Aug 2019

Cited by 11 | Viewed by 4312

Abstract

A mutant defective in the biosynthesis of thermospermine, acaulis5 (acl5), shows a dwarf phenotype with excess xylem vessels in Arabidopsis thaliana. Exogenous supply of thermospermine remarkably represses xylem differentiation in the root of seedlings, indicating the role of thermospermine in [...] Read more.

A mutant defective in the biosynthesis of thermospermine, acaulis5 (acl5), shows a dwarf phenotype with excess xylem vessels in Arabidopsis thaliana. Exogenous supply of thermospermine remarkably represses xylem differentiation in the root of seedlings, indicating the role of thermospermine in proper repression of xylem differentiation. However, the effect of thermospermine has rarely been investigated in other plant species. In this paper, we examined its effect on the growth and gene expression in rice seedlings. When grown with thermospermine, rice seedlings had no clearly enlarged metaxylem vessels in the root. Expression of OsACL5 was reduced in response to thermospermine, suggesting a negative feedback control of thermospermine biosynthesis like in Arabidopsis. Unlike Arabidopsis, however, rice showed up-regulation of phloem-expressed genes, OsHB5 and OsYSL16, by one-day treatment with thermospermine. Furthermore, expression of OsPAO2 and OsPAO6, encoding extracellular polyamine oxidase whose orthologs are not present in Arabidopsis, was induced by both thermospermine and spermine. These results suggest that thermospermine affects the expression of a subset of genes in rice different from those affected in Arabidopsis. Full article

(This article belongs to the Special Issue Plant Polyamines)

► Show Figures

Figure 1

14 pages, 3218 KiB

Open AccessArticle

Genetic Characterization of Apulian Olive Germplasm as Potential Source in New Breeding Programs

by S. Sion, F. Taranto, C. Montemurro, G. Mangini, S. Camposeo, V. Falco, A. Gallo, G. Mita, O. Saddoud Debbabi, F. Ben Amar, S. Pavan, V. Roseti and M. M. Miazzi

Plants 2019, 8(8), 268; https://doi.org/10.3390/plants8080268 - 05 Aug 2019

Cited by 28 | Viewed by 4264

Abstract

The olive is a fruit tree species with a century-old history of cultivation in the Mediterranean basin. In Apulia (Southern Italy), the olive is of main social, cultural and economic importance, and represents a hallmark of the rural landscape. However, olive cultivation in [...] Read more.

The olive is a fruit tree species with a century-old history of cultivation in the Mediterranean basin. In Apulia (Southern Italy), the olive is of main social, cultural and economic importance, and represents a hallmark of the rural landscape. However, olive cultivation in this region is threatened by the recent spread of the olive quick decline syndrome (OQDS) disease, thus there is an urgent need to explore biodiversity and search for genetic sources of resistance. Herein, a genetic variation in Apulian olive germplasm was explored, as a first step to identify genotypes with enhanced bio-agronomic traits, including resistance to OQDS. A preselected set of nuclear microsatellite markers allowed the acquisition of genotypic profiles, and to define genetic relationships between Apulian germplasm and widespread cultivars. The analysis highlighted the broad genetic variation in Apulian accessions and the presence of different unique genetic profiles. The results of this study lay a foundation for the organization of new breeding programs for olive genetic improvement. Full article

(This article belongs to the Section Plant Genetics, Genomics and Biotechnology)

► Show Figures

Graphical abstract

22 pages, 4237 KiB

Open AccessArticle

Hybrid-Transcriptome Sequencing and Associated Metabolite Analysis Reveal Putative Genes Involved in Flower Color Difference in Rose Mutants

by Ping Huang, Furong Lin, Bin Li and Yongqi Zheng

Plants 2019, 8(8), 267; https://doi.org/10.3390/plants8080267 - 05 Aug 2019

Cited by 12 | Viewed by 4559

Abstract

Gene mutation is a common phenomenon in nature that often leads to phenotype differences, such as the variations in flower color that frequently occur in roses. With the aim of revealing the genomic information and inner mechanisms, the differences in the levels of [...] Read more.

Gene mutation is a common phenomenon in nature that often leads to phenotype differences, such as the variations in flower color that frequently occur in roses. With the aim of revealing the genomic information and inner mechanisms, the differences in the levels of both transcription and secondary metabolism between a pair of natural rose mutants were investigated by using hybrid RNA-sequencing and metabolite analysis. Metabolite analysis showed that glycosylated derivatives of pelargonidin, e.g., pelargonidin 3,5 diglucoside and pelargonidin 3-glucoside, which were not detected in white flowers (Rosa ‘Whilte Mrago Koster’), constituted the major pigments in pink flowers. Conversely, the flavonol contents of petal, such as kaempferol-3-glucoside, quercetin 3-glucoside, and rutin, were higher in white flowers. Hybrid RNA-sequencing obtained a total of 107,280 full-length transcripts in rose petal which were annotated in major databases. Differentially expressed gene (DEG) analysis showed that the expression of genes involved in the flavonoid biosynthesis pathway was significantly different, e.g., CHS, FLS, DFR, LDOX, which was verified by qRT-PCR during flowering. Additionally, two MYB transcription factors were found and named RmMYBAN2 and RmMYBPA1, and their expression patterns during flowering were also analyzed. These findings indicate that these genes may be involved in the flower color difference in the rose mutants, and competition between anthocyanin and flavonol biosynthesis is a primary cause of flower color variation, with its regulation reflected by transcriptional and secondary metabolite levels. Full article

► Show Figures

Figure 1

10 pages, 2316 KiB

Open AccessArticle

A Convenient Plant-Based Detection System to Monitor Androgenic Compound in the Environment

by Dong-Gwan Kim, Ramin Bahmani, Jae-Heung Ko and Seongbin Hwang

Plants 2019, 8(8), 266; https://doi.org/10.3390/plants8080266 - 05 Aug 2019

Viewed by 2721

Abstract

Environmental androgen analogues act as endocrine disruptors, which inhibit the normal function of androgen in animals. In the present work, through the expression of a chimeric gene specified for the production of the anthocyanin in response to androgen DHT (dihydrotestosterone), we generated an [...] Read more.

Environmental androgen analogues act as endocrine disruptors, which inhibit the normal function of androgen in animals. In the present work, through the expression of a chimeric gene specified for the production of the anthocyanin in response to androgen DHT (dihydrotestosterone), we generated an indicator Arabidopsis that displays a red color in leaves in the presence of androgen compounds. This construct consists of a ligand-binding domain of the human androgen receptor gene and the poplar transcription factor gene PtrMYB119, which is involved in anthocyanin biosynthesis in poplar and Arabidopsis. The transgenic Arabidopsis XVA-PtrMYB119 displayed a red color in leaves in response to 10 ppm DHT, whereas it did not react in the presence of other androgenic compounds. The transcript level of PtrMYB119 peaked at day 13 of DHT exposure on agar media and then declined to its normal level at day 15. Expressions of anthocyanin biosynthesis genes including chalcone flavanone isomerase, chalcone synthase, flavanone 3-hydroxylase, dihydroflavonol 4-reductase, UFGT (UGT78D2), and anthocyanidin synthase were similar to that of PtrMYB119. It is assumed that this transgenic plant can be used by nonscientists for the detection of androgen DHT in the environment and samples such as food solution without any experimental procedures. Full article

(This article belongs to the Section Plant Molecular Biology)

► Show Figures

Figure 1

14 pages, 4401 KiB

Open AccessEditor’s ChoiceArticle

Antioxidant, Antidiabetic, and Anticholinesterase Activities and Phytochemical Profile of Azorella glabra Wedd

by Immacolata Faraone, Dilip K. Rai, Daniela Russo, Lucia Chiummiento, Eloy Fernandez, Alka Choudhary and Luigi Milella

Plants 2019, 8(8), 265; https://doi.org/10.3390/plants8080265 - 03 Aug 2019

Cited by 29 | Viewed by 4968

Abstract

Oxidative stress is involved in different diseases, such as diabetes and neurodegenerative diseases. The genus Azorella includes about 70 species of flowering plant species; most of them are commonly used as food and in particular as a tea infusion in the Andean region [...] Read more.

Oxidative stress is involved in different diseases, such as diabetes and neurodegenerative diseases. The genus Azorella includes about 70 species of flowering plant species; most of them are commonly used as food and in particular as a tea infusion in the Andean region of South America in folk medicine to treat various chronic diseases. Azorella glabra Wedd. aerial parts were firstly analyzed for their in vitro antioxidant activity using different complementary assays. In particular, radical scavenging activity was tested against biological neutral radical DPPH; ferric reducing power and lipid peroxidation inhibitory capacity (FRAP and Beta-Carotene Bleaching tests) were also determined. The Relative Antioxidant Capacity Index (RACI) was used to compare data obtained by different assays. Then, the inhibitory ability of samples was investigated against α-amylase and α-glucosidase enzymes involved in diabetes and against acetylcholinesterase and butyrylcholinesterase enzymes considered as strategy for the treatment of Parkinson’s or Alzheimer’s diseases. Moreover, the phytochemical profile of the sample showing the highest RACI (1.35) and interesting enzymatic activities (IC₅₀ of 163.54 ± 9.72 and 215.29 ± 17.10 μg/mL in α-glucosidase and acetylcholinesterase inhibition, respectively) was subjected to characterization and quantification of its phenolic composition using LC-MS/MS analysis. In fact, the ethyl acetate fraction derived from ethanol extract by liquid/liquid extraction showed 29 compounds, most of them are cinnamic acid derivatives, flavonoid derivatives, and a terpene. To the best of our knowledge, this is the first report about the evaluation of significant biological activities and phytochemical profile of A. glabra, an important source of health-promoting phytochemicals. Full article

(This article belongs to the Special Issue Medicinal Plants)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Plants, Volume 8, Issue 8 (August 2019) – 50 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI