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1.
GM Crops Food ; 12(1): 57-70, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877304

RESUMO

Hybrid seeds of several important crops with supreme qualities including yield, biotic and abiotic stress tolerance have been cultivated for decades. Thus far, a major challenge with hybrid seeds is that they do not have the ability to produce plants with the same qualities over subsequent generations. Apomixis, an asexual mode of reproduction by avoiding meiosis, exists naturally in flowering plants, and ultimately leads to seed production. Apomixis has the potential to preserve hybrid vigor for multiple generations in economically important plant genotypes. The evolution and genetics of asexual seed production are unclear, and much more effort will be required to determine the genetic architecture of this phenomenon. To fix hybrid vigor, synthetic apomixis has been suggested. The development of MiMe (mitosis instead of meiosis) genotypes has been utilized for clonal gamete production. However, the identification and parental origin of genes responsible for synthetic apomixis are little known and need further clarification. Genome modifications utilizing genome editing technologies (GETs), such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (cas), a reverse genetics tool, have paved the way toward the utilization of emerging technologies in plant molecular biology. Over the last decade, several genes in important crops have been successfully edited. The vast availability of GETs has made functional genomics studies easy to conduct in crops important for food security. Disruption in the expression of genes specific to egg cell MATRILINEAL (MTL) through the CRISPR/Cas genome editing system promotes the induction of haploid seed, whereas triple knockout of the Baby Boom (BBM) genes BBM1, BBM2, and BBM3 cause embryo arrest and abortion, which can be fully rescued by male-transmitted BBM1. The establishment of synthetic apomixis by engineering the MiMe genotype by genome editing of BBM1 expression or disruption of MTL leads to clonal seed production and heritability for multiple generations. In the present review, we discuss current developments related to the use of CRISPR/Cas technology in plants and the possibility of promoting apomixis in crops to preserve hybrid vigor. In addition, genetics, evolution, epigenetic modifications, and strategies for MiMe genotype development are discussed in detail.


Assuntos
Apomixia , Sistemas CRISPR-Cas , Produtos Agrícolas/genética , Edição de Genes , Vigor Híbrido , Sementes
2.
BMC Ecol ; 20(1): 49, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867734

RESUMO

BACKGROUND: Vertebrate-mediated seed dispersal is probably the main long distance dispersal mode. Through endozoochory, large mammals act as mobile links between habitats within and among forest patches. Along with other factors, their feeding regimes do affect their contribution as dispersal vectors. We conducted a cross-species comparative experiment involving two herbivores, red deer and roe deer; and two opportunistic omnivores, wild boar and brown bear, all occurring in the forest and steppe-forest ecotone habitats of the south-eastern Caspian region. We compared their role as endozoochorous seed dispersal agents by monitoring seedling emergence in their dungs under greenhouse and natural conditions. RESULTS: In total, 3078 seedlings, corresponding to 136 plant taxa sprouted from 445 paired dung sub-samples, under greenhouse and natural conditions. Only 336 seedlings, corresponding to 36 plant taxa, emerged under natural conditions, among which five taxa did not appear under greenhouse conditions. Graminoids and forbs composed 91% of the seedlings in the greenhouse whereas shrubs were more abundant under natural conditions, representing 55% of the emerged seedlings. Under greenhouse conditions, first red deer and then wild boar dispersed more species than the other two mammals, while under natural conditions brown bear was the most effective vector. We observed remarkably higher species richness and seedling abundance per dung sub-sample under buffered greenhouse conditions than we did under natural conditions. CONCLUSIONS: The four sympatric mammals studied provided different seed dispersal services, both in terms of seedling abundance and species richness and may therefore be regarded as complementary. Our results highlight a positive bias when only considering germination under buffered greenhouse conditions. This must be taken into account when planning management options to benefit plant biodiversity based on the dispersal services concluded from greenhouse experiments.


Assuntos
Cervos , Dispersão de Sementes , Animais , Germinação , Herbivoria , Plântula , Sementes
3.
Phytochemistry ; 178: 112480, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32768716

RESUMO

Paeonia ostii var. lishizhenii has been approved as a woody oil crop with the outstanding characteristic of abundant α-linolenic acid (C18:3, ALA) in its seed oil. The stearoyl-ACP desaturase gene (SAD) regulates the first key step from stearic acid (C18:0, SA) to oleic acid (C18:1, OA) in the ALA biosynthetic pathway, but its functional characterization in P. ostii var. lishizhenii is absent to date. In this study, a key PoSAD gene (1719 bp in length) was acquired from endosperm of P. ostii var. lishizhenii by transcriptome sequencing analysis and the RACE (rapid-amplification of cDNA ends) method. Bioinformatic analysis of the PoSAD protein showed high homology (ranging from 90.4% to 94.4%) and similar physical and chemical properties to SAD from other higher plants, indicating that it encodes a putative stearoyl-ACP desaturase. Analysis of cis-acting elements found several endosperm tissue-specific motifs; i.e., one Prolamin box, thirteen DOFCOREs and one RY repeat in its promoter. The results of the qRT-PCR experiments verified that PoSAD was most highly expressed in developing endosperm at 59 days after pollination (53.7 times that in shoots) compared with that in roots (1.4 times), stems (2.5 times), leaves (3.1 times), petals (13.1 times) and stamens (46.0 times). Meanwhile, the fatty acid contents in P. ostii var. lishizhenii endosperm at seven growth stages were compared with variation in PoSAD expression. Heterologous expression of PoSAD significantly decreased SA and increased OA content, which effectively reduced the ratios of SA to OA in Saccharomyces cerevisiae and Arabidopsis thaliana. However, contents and ratios of palmitic acid (C16:0) and palmitoleic acid (C16:1) were stable in transgenic yeast, and palmitoleic acid remained absent in transgenic A. thaliana seeds. These results illustrate that PoSAD plays an essential role in endosperm development of P. ostii var. lishizhenii, strictly in catalysis of SA desaturation and OA biosynthesis but without functioning in PA desaturation. The results contribute to our understanding of the characterization of PoSAD in OA biosynthesis in P. ostii var. lishizhenii.


Assuntos
Ácido Oleico , Paeonia , Oxigenases de Função Mista , Proteínas de Plantas , Sementes
4.
Pestic Biochem Physiol ; 169: 104647, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32828366

RESUMO

Peptidase inhibitors (PIs) are plant proteins that are found to be effective against various digestive peptidases of insects. The present study isolated and characterized a trypsin inhibitor from mature dry seeds of Mucuna pruriens and investigated its effect against Bactrocera cucurbitae larvae, a major pest of cucurbitaceae crops, for its inhibitory activity. The purified trypsin inhibitor from M. pruriens seeds gave a molecular weight of ~11 kDa on SDS-PAGE. M. pruriens trypsin inhibitor (MPTI) exhibited inhibitory effect on growth of melon fruit fly larvae (64-72 h old) as it resulted in prolongation of larval, pupal and total development period. There was a significant increase in larval mortality with increase in concentration of MPTI. Nutritional indices decreased significantly at all the concentrations of MPTI. Quantitative RT- PCR revealed that the mRNA expression level of trypsin and chymotrypsin genes was reduced while that of GST, esterases, AP, SOD and catalase were enhanced. It can therefore be inferred that MPTI can serve as a promising agent for biocontrol that can reduce the problems caused by fruit fly and other similar catastrophic pests. This study provides the fundamental information for future successful strategies for pest management.


Assuntos
Mucuna , Tephritidae , Animais , Fenômenos Fisiológicos do Sistema Digestório , Larva , Sementes , Inibidores da Tripsina
5.
Ecotoxicol Environ Saf ; 202: 110918, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800253

RESUMO

This work evaluates different generations of transgenic (cp4-EPSPS gene) and non-transgenic soybean plants through proteomics and metabolomics. For proteomics purpose, 24 differentially abundant protein spots were found through 2-D DIGE, being 4 belonging to transgenic plants. From this total, 19 were successfully identified, storage proteins as predominant class. Some identified proteins are involved in growing and cell division, and stress response, such as LEA and dehydrin. For metabolomics, 17 compounds were putatively annotated, mainly belonging to the secondary metabolism, such as flavonoids. From these analyzes, all generations and varieties of the soybean are prone to be differentiate by PLS-DA. According to our results, transgenic plants appear to be more stable than non-transgenic ones. In addition, the omics-based approaches allowed access some relations between those differential spot proteins and metabolites, mainly those storage proteins and flavonoid.


Assuntos
Plantas Geneticamente Modificadas/fisiologia , Soja/fisiologia , Metabolômica , Plantas Geneticamente Modificadas/metabolismo , Proteômica , Sementes/metabolismo , Soja/genética , Soja/metabolismo
6.
BMC Ecol ; 20(1): 48, 2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32861248

RESUMO

BACKGROUND: Salvia is a large, diverse, and polymorphous genus of the family Lamiaceae, comprising about 900 ornamentals, medicinal species with almost cosmopolitan distribution in the world. The success of Salvia limbata seed germination depends on a numerous ecological factors and stresses. We aimed to analyze Salvia limbata seed germination under four ecological stresses of salinity, drought, temperature and pH, with application of artificial intelligence modeling techniques such as MLR (Multiple Linear Regression), and MLP (Multi-Layer Perceptron). The S.limbata seeds germination was tested in different combinations of abiotic conditions. Five different temperatures of 10, 15, 20, 25 and 30 °C, seven drought treatments of 0, -2, -4, -6, -8, -10 and -12 bars, eight treatments of salinity containing 0, 50, 100.150, 200, 250, 300 and 350 mM of NaCl, and six pH treatments of 4, 5, 6, 7, 8 and 9 were tested. Indeed 228 combinations were tested to determine the percentage of germination for model development. RESULTS: Comparing to the MLR, the MLP model represents the significant value of R2 in training (0.95), validation (0.92) and test data sets (0.93). According to the results of sensitivity analysis, the values of drought, salinity, pH and temperature are respectively known as the most significant variables influencing S. limbata seed germination. Areas with high moisture content and low salinity in the soil have a high potential to seed germination of S. limbata. Also, the temperature of 18.3 °C and pH of 7.7 are proposed for achieving the maximum number of germinated S. limbata seeds. CONCLUSIONS: Multilayer perceptron model helps managers to determine the success of S.limbata seed planting in agricultural or natural ecosystems. The designed graphical user interface is an environmental decision support system tool for agriculture or rangeland managers to predict the success of S.limbata seed germination (percentage) in different ecological constraints of lands.


Assuntos
Germinação , Salvia , Inteligência Artificial , Ecossistema , Sementes , Temperatura
7.
Ecotoxicol Environ Saf ; 202: 111011, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800236

RESUMO

Boron (B) deficiency and surplus are the main factors that affect plant growth and yield. A better understanding of the response mechanisms of plant reproductive organs to stress induced by B deficiency and surplus could provide new insights to potential strategies for improving seed yield and quality. In this study, we aimed to elucidate the mechanisms of tolerance to B-induced stress in the reproductive organs of alfalfa (Medicago sativa L. cv. 'Aohan'). We initially used five B concentrations (0 mg B L-1, 400 mg B L-1, 800 mg B L-1, 1200 mg B L-1, and 1600 mg B L-1) to determine the B deficient, sufficient, and surplus levels in the field. Secondly, we examined changes in metabolite profiles of alfalfa 'Aohan' reproductive organs in response to B deficiency (0 mg B L-1), B sufficiency (800 mg B L-1), and B surplus (1600 mg B L-1) conditions using gas chromatography-mass spectrometry (GC-MS). Flowers and seeds from alfalfa 'Aohan' showed different metabolite profiles and resistance capacity under B deficiency and surplus conditions. B deficiency led to the excessive accumulation of sugars and phenolic compounds in alfalfa 'Aohan' and seeds, respectively, thus causing abscission or the abortion of reproductive organs. In contrast, B surplus severely reduced the levels of metabolites associated with amino acid and carbohydrate metabolism, resulting in the flowers falling and, therefore, low seed yield. Overall, B deficiency predominantly reduced seed yield and quality of alfalfa 'Aohan', while B surplus mainly affected seed yield of alfalfa 'Aohan'.


Assuntos
Boro/deficiência , Boro/toxicidade , Células Germinativas Vegetais/efeitos dos fármacos , Medicago sativa/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Poluentes do Solo/toxicidade , Aminoácidos/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células Germinativas Vegetais/metabolismo , Medicago sativa/metabolismo , Metabolômica , Sementes/metabolismo , Poluentes do Solo/metabolismo
8.
Oecologia ; 193(4): 937-947, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32783114

RESUMO

The mechanisms driving species diversity in the context of Janzen-Connell model are best understood by evaluating not only conspecific distance-dependent (CDD) seedling performance, but also replacement of conspecific seedlings by heterospecific seedlings beneath adult trees. We evaluated CDD and replacement as a log response ratio of seedling performance (height, age) directly beneath and at a distance from adult plants in a temperate forest, and examined the log response ratio of that between conspecifics and heterospecifics beneath adults for five hardwood species with different ecological traits (e.g., seed size, mycorrhizal type, relative abundance). CDD was greater in three small-seeded species with arbuscular mycorrhizae (AM) associations than it was in two large-seeded species with ectomycorrhizae (EM) associations. Replacement was also higher for small-seeded AM species compared to large-seeded EM species, resulting in a strong, positive relationship between CDD and replacement. The traits suggest that small-seeded AM seedlings are more likely to be replaced by heterologous seedlings beneath the adults than large-seeded EM seedlings, probably due to that the small-seeded AM species are more susceptible to attack by plant natural enemies (e.g., soil pathogens, leaf diseases). As a result, small-seeded AM species had lower relative abundances compared to large-seeded EM species. This study suggests that either seed size or associations with microorganisms play an important role in driving forest diversity by regulating replacement and CDD, although relative importance of the two traits (i.e., seed size, mycorrhizal type) remains unclear, because of the autocorrelation between the two traits for the five species studied.


Assuntos
Micorrizas , Plântula , Florestas , Sementes , Árvores
9.
PLoS Biol ; 18(7): e3000564, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32701952

RESUMO

Amyloids are protein aggregates with a highly ordered spatial structure giving them unique physicochemical properties. Different amyloids not only participate in the development of numerous incurable diseases but control vital functions in archaea, bacteria and eukarya. Plants are a poorly studied systematic group in the field of amyloid biology. Amyloid properties have not yet been demonstrated for plant proteins under native conditions in vivo. Here we show that seeds of garden pea Pisum sativum L. contain amyloid-like aggregates of storage proteins, the most abundant one, 7S globulin Vicilin, forms bona fide amyloids in vivo and in vitro. Full-length Vicilin contains 2 evolutionary conserved ß-barrel domains, Cupin-1.1 and Cupin-1.2, that self-assemble in vitro into amyloid fibrils with similar physicochemical properties. However, Cupin-1.2 fibrils unlike Cupin-1.1 can seed Vicilin fibrillation. In vivo, Vicilin forms amyloids in the cotyledon cells that bind amyloid-specific dyes and possess resistance to detergents and proteases. The Vicilin amyloid accumulation increases during seed maturation and wanes at germination. Amyloids of Vicilin resist digestion by gastrointestinal enzymes, persist in canned peas, and exhibit toxicity for yeast and mammalian cells. Our finding for the first time reveals involvement of amyloid formation in the accumulation of storage proteins in plant seeds.


Assuntos
Amiloide/metabolismo , Ervilhas/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/metabolismo , Amiloide/ultraestrutura , Detergentes/farmacologia , Escherichia coli/metabolismo , Íons , Pancreatina/metabolismo , Ervilhas/efeitos dos fármacos , Pepsina A/metabolismo , Agregados Proteicos , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/farmacologia , Proteínas de Armazenamento de Sementes/ultraestrutura
10.
J Indian Soc Pedod Prev Dent ; 38(2): 145-151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32611860

RESUMO

Background: Complete elimination of microorganisms from the root canals is the important key for the successful endodontic treatment. Constant emergence of resistant strains and adverse effects of synthetic drugs has led to the search of effective herbal alternatives. Nutmeg (Myristica fragrans) is one such spice used for its various medicinal activities. Aims: To evaluate the antimicrobial effect of M. fragrans on common endodontic pathogens of primary tooth. Materials and Methods: Essential oil of nutmeg was extracted by hydrodistillation method, and its phytoconstituents were determined by thin-layer chromatography (TLC), high-performance TLC, and gas chromatography-mass spectrometry analysis. Minimum inhibitory concentration of essential oil against standard strains of common endodontic pathogens (Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Candida albicans, Lactobacillus casei, Actinomyces viscosus, Prevotella intermedia, and Porphyromonas gingivalis) was determined by serial tube dilution method. Results: Essential oil of M. fragrans was effective against all tested endodontic microorganisms. Discussion: The active components of essential oil of nutmeg such as myristicin, myristic acid, trimyristin, elemicin, and safrole have good antimicrobial activity and are effective against endodontic microorganisms. Conclusion: M. fragrans can be used as an effective medicament in the treatment of endodontic infections.


Assuntos
Anti-Infecciosos , Myristica , Óleos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Sementes
11.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2219-2226, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32715684

RESUMO

Allelopathic effects of Miscanthus floridulus at different growth stages on Brassica peki-nensis, Lactuca sativa, and Oryza sativa were examined using six parameters of seed germination and seedling growth, including germination rate, germination speed index, germination index, root length, stem length, and biomass. The results showed that the allelopathic effects of M. floridulus leaf extract were stronger than that of stem extract, with the germination index and biomass of reci-pient plants treated by leaf extract being significantly lower than those treated by stem extract. The allelopathic effect of M. floridulus in the withering stage was stronger than that in the vigorous growth stage. There was a significant dose-effect relationship between the concentrations of leaf extract and the allelopathic effects on three different receptor plants. The higher the extract concentration was, the stronger the allelopathic inhibition was. Leaf extract of M. floridulus could completely inhibit all the germination indices of B. pekinensis and L. sativa at the concentrations of 0.075 and 0.10 g·mL-1, respectively. The inhibition rates of 0.10 g·mL-1 leaf extract on germination rate, germination speed index, and germination index of O. sativa were 13.8%, 27.2% and 19.3%, respectively. Leaf extract of M. floridulus could completely inhibit all the growth indices of B. pekinensis and L. sativa at the concentrations of 0.05 and 0.10 g·mL-1, respectively. However, the inhibition rates of 0.10 g·mL-1 leaf extract on root length, stem length, and biomass of O. sativa were 64.6%, 92.9% and 21.8%, respectively. In summary, according to the comprehensive allelopathy response index (SE) of seed germination and seedling growth, the susceptibility of the three tested species to the extracts of M. floridulus was B. pekinensis (Cruciferae) > L. sativa (Compositae) > O. sativa (Gramineae).


Assuntos
Alelopatia , Plântula , Germinação , Extratos Vegetais , Poaceae , Sementes
12.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2264-2270, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32715690

RESUMO

We examined the effects of root extracts of Haloxylon ammodendron and Beta vulgaris in Chenopodiaceae extracted by water and ethanol on seed germination and haustorium formation of Cistanche deserticola by filter paper culture dish method. The results showed that only adding root extract had no effect on seed germination and haustorium formation of C. deserticola. The germination rate of C. deserticola seeds treated by adding 10 mg·kg-1 gibberellin to the root extracted by ethanol was not significantly different from that of the control (GA3), whereas those treated by adding gibberellin to the ethanol extract of two kinds of host root was increased by more than 10 times. The germination rate of C. deserticola seeds in the treatment with adding 1 mg·kg-1 fluridone (FL) to root extract was not significantly different from that in the control with only fluridone, while those in the treatment with B. vulgaris root water extraction was the highest (39.4%). Compared to the treatment of adding gibberellin to the root extract, the germination rate of C. deserticola seeds was only increased. When FL was added to the host root extract, the haustorium was formed on the germination tube, with the formation rate of the ethanol extraction group being the highest (16.2%). Seed germination rate of C. deserticola increased to 52.3% when GA3 and FL were added to the ethanol extract of H. ammodendron, but the formation rate of haustorium was not different from that of FL treatment. Only 6.7% of the seed formation haustorium in the control was significantly lower than that in FL treatment. There were differences in the position and shape of the haustorium of C. deserticola seeds under different treatments. The haustorium produced by adding the extract of the host root mostly appeared at the top of the bud tube, and many papillae raised into claws. The haustorium of FL treatment without adding the extract of the host root mostly appeared at the bottom or the top of the bud tube splitting. The results indicated that ethanol extraction and water extraction could extract the substances that could promote the formation of C. deserticola seeds haustorium from the host root, but did not affect seed germination. GA3 and FL could significantly improve the germination rate of C. deserticola seeds, but the formation of the haustorium was affected by some substances in the host root extract.


Assuntos
Cistanche , Germinação , Giberelinas , Extratos Vegetais , Sementes
13.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2271-2278, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32715691

RESUMO

Invasive plants can inhibit the survival and reproduction of native species through alle-lopathy. It is not clear whether the native plants, especially the mosses in the ground layer, inf-luence the invasive plants. In this study, we examined the effects of two native moss species, Brachythecium plumosum and Plagiomnium venustum, on two malignant invasive plants, Echinochloa crusgalli and Daucus carota. The effects of mosses on seed germination and seedling growth of both invasive species were determined based on the clump structure and allelopathy of the mosses. The germination rate, germination potential and germination index of the two invasive species were significantly inhibited when seeds fallen on or into the moss clump, with an order of inhibition effect: above moss clump>below moss clump>no moss. Radicle length and radicle/plumule of D. Carota were significantly affected when seeds fallen into the moss clump. Moss water extracts significantly reduced germination rate, germination potential, and germination index of the two invasive plants, with these effects being concentration-dependent. To some extent, moss water extracts increased the plumule length, radicle length and radicle/plumule of D. Carota seedlings, but without effect on E. crusgalli. Both mosses showed inhibitory effects on seed germination and seedling growth of two invasive plants, with higher sensitivity of E. crusgalli than D. Carota. Along with the increases in concentration of water extract, stronger inhibitory effects were found. Therefore, mosses could partially inhibit seed germination and seedling growth of invasive plants.


Assuntos
Bryopsida , Plântula , Alelopatia , Germinação , Sementes
14.
Ecol Lett ; 23(9): 1370-1379, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32602645

RESUMO

Environmental variability can lead to dispersal: why stay put if it is better elsewhere? Without clues about local conditions, the optimal strategy is often to disperse a set fraction of offspring. Many habitats contain environmentally differing sub-habitats. Is it adaptive for individuals to sense in which sub-habitat they find themselves, using environmental clues, and respond plastically by altering the dispersal rates? This appears to be done by some plants which produce dimorphic seeds with differential dispersal properties in response to ambient temperature. Here we develop a mathematical model to show, that in highly variable environments, not only does sensing promote plasticity of dispersal morph ratio, individuals who can sense their sub-habitat and respond in this way have an adaptive advantage over those who cannot. With a rise in environmental variability due to climate change, our understanding of how natural populations persist and respond to changes has become crucially important.


Assuntos
Ecossistema , Sementes , Mudança Climática , Humanos , Plantas
15.
Plant Dis ; 104(9): 2489-2497, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32631201

RESUMO

Some Pythium spp. cause damping off and root rot in soybeans and other crop species. One of the most effective management tools to reduce disease is host resistance; however, little is known about resistance in soybean to Pythium spp. The soybean nested associated mapping (SoyNAM) parent lines are a set of germplasms that were crossed to a single hub parent to create recombinant inbred line populations for the purpose of mapping agronomic traits. The SoyNAM parents were screened for resistance to Pythium lutarium, Pythium oopapillum, Pythium sylvaticum, and Pythium torulosum in separate assays to evaluate seed and root rot severity. Of the 40 SoyNAM parents, only 'Maverick' was resistant to the four species tested; however, 13 were resistant to three species. Other lines were resistant to two, one, or none of the species tested. Correlations between seed and root rot severity for the lines assessed were weak or insignificant. Results indicate that mechanisms of resistance to seed and root rot caused by Pythium spp. may not necessarily be the same.


Assuntos
Pythium , Doenças das Plantas , Sementes , Soja
16.
PLoS One ; 15(7): e0235484, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634144

RESUMO

Accurate identification of crop varieties grown by farmers is crucial, among others, for crop management, food security and varietal development and dissemination purposes. One may expect varietal identification to be more challenging in the context of developing countries where literacy and education are limited and informal seed systems and seed recycling are common. This paper evaluates the extent to which smallholder farmers misidentify their wheat varieties in Ethiopia and explores the associated factors and their implications. The study uses data from a nationally representative wheat growing sample household survey and DNA fingerprinting of seed samples from 3,884 wheat plots in major wheat growing zones of Ethiopia. 28-34% of the farmers correctly identified their wheat varieties. Correct identification was positively associated with farmer education and seed purchases from trusted sources (cooperatives or known farmers) and negatively associated with seed recycling. Farmers' varietal identification thereby is problematic and leads to erroneous results in adoption and impact assessments. DNA fingerprinting can enhance varietal identification but remains mute in the identification of contextual and explanatory factors. Thus, combining household survey and DNA fingerprinting approaches is needed for reliable varietal adoption and impact assessments, and generate useful knowledge to inform policy recommendations related to varietal replacement and seed systems development.


Assuntos
Produtos Agrícolas/genética , Impressões Digitais de DNA , Sementes/genética , Triticum/genética , Agricultura , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Etiópia , Fazendeiros , Humanos , Sementes/classificação , Sementes/crescimento & desenvolvimento , Triticum/classificação , Triticum/crescimento & desenvolvimento
17.
PLoS One ; 15(7): e0232860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645001

RESUMO

Limited information is available that seed biopriming with plant growth-promoting Enterobacter spp. play a prominent role to enhance vegetative growth of plants. Contrary to Enterobacter cloacae, Enterobacter hormaechei is a less-studied counterpart despite its vast potential in plant growth-promotion mainly through the inorganic phosphorus (P) and potassium (K) solubilization abilities. To this end, 18 locally isolated bacterial pure cultures were screened and three strains showed high P- and K-solubilizing capabilities. Light microscopy, biochemical tests and 16S rRNA gene sequencing revealed that strains 15a1 and 40a were closely related to Enterobacter hormaechei while strain 38 was closely related to Enterobacter cloacae (Accession number: MN294583; MN294585; MN294584). All Enterobacter spp. shared common plant growth-promoting traits, namely nitrogen (N2) fixation, indole-3-acetic acid production and siderophore production. The strains 38 and 40a were able to produce gibberellic acid, while only strain 38 was able to secrete exopolysaccharide on agar. Under in vitro germination assay of okra (Abelmoschus esculentus) seeds, Enterobacter spp. significantly improved overall germination parameters and vigor index (19.6%) of seedlings. The efficacy of root colonization of Enterobacter spp. on the pre-treated seedling root tips was confirmed using Scanning Electron Microscopy (SEM). The pot experiment of bioprimed seeds of okra seedling showed significant improvement of the plant growth (> 28%) which corresponded to the increase of P and K uptakes (> 89%) as compared to the uninoculated control plants. The leaf surface area and the SPAD chlorophyll index of bioprimed plants were increased by up to 29% and 9% respectively. This report revealed that the under-explored species of P- and K-solubilizing Enterobacter hormaechei sp. with multiple plant beneficial traits presents a great potential sustainable approach for enhancement of soil fertility and P and K uptakes of plants.


Assuntos
Abelmoschus/crescimento & desenvolvimento , Enterobacter/fisiologia , Fósforo/metabolismo , Potássio/metabolismo , Sementes/microbiologia , Abelmoschus/classificação , Abelmoschus/metabolismo , Abelmoschus/microbiologia , Contenção de Riscos Biológicos , Enterobacter/isolamento & purificação , Germinação , Tipagem Molecular , Desenvolvimento Vegetal , RNA Ribossômico 16S , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
18.
PLoS One ; 15(7): e0235434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649700

RESUMO

The genetic diversity of North American soybean cultivars has been largely influenced by a small number of ancestors. High yielding breeding lines that possess exotic pedigrees have been developed, but identifying beneficial exotic alleles has been difficult as a result of complex interactions of yield alleles with genetic backgrounds and environments as well as the highly quantitative nature of yield. PI 416937 has been utilized in the development of many high yielding lines that have been entered into the USDA Southern States Uniform Tests over the past ~20 years. The primary goal of this research was to identify genomic regions under breeding selection from PI 416937 and introduce a methodology for identifying and potentially utilizing beneficial diversity from lines prevalent in the ancestry of elite cultivars. Utilizing SoySNP50K Infinium BeadChips, 52 high yielding PI 416937-derived lines as well as their parents were genotyped to identify PI 416937 alleles under breeding selection. Nine genomic regions across three chromosomes and 17 genomic regions across seven chromosomes were identified where PI 416937 alleles were under positive or negative selection. Minimal significant associations between PI 416937 alleles and yield were observed in replicated yield trials of five RIL populations, highlighting the difficulty of consistently detecting yield associations.


Assuntos
Cruzamento , Variação Genética/genética , Soja/genética , Alelos , Mapeamento Cromossômico , Cromossomos de Plantas , Genoma de Planta/genética , Genômica , Genótipo , Humanos , Locos de Características Quantitativas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Soja/crescimento & desenvolvimento , Estados Unidos
19.
Anticancer Res ; 40(8): 4529-4535, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727783

RESUMO

BACKGROUND/AIM: Although ginseng seed oil (GSO) appears to have various roles in the body, its anti-cancer effect has not been investigated. Tamoxifen is widely used to treat estrogen receptor-positive (ER+) breast cancer but shows adverse effects with drug resistance. This study investigated the effect of GSO in ER+ breast cancer cell growth. MATERIALS AND METHODS: Cell viability assays, western blots and Annexin V staining were conducted to examine cell viability and apoptosis. The synergistic effect of tamoxifen in combination with GSO or oleic acid (OA) was determined. RESULTS: GSO and OA caused apoptosis of MCF-7 ER+ breast cancer cells and had synergistic effects with tamoxifen in inhibiting tamoxifen-resistant MCF-7 (MCF-7TAMR) ER+ breast cancer cell growth. CONCLUSION: GSO may block ER+ breast cancer recurrence in combination with tamoxifen.


Assuntos
Neoplasias da Mama/metabolismo , Ácido Oleico/farmacologia , Panax/química , Óleos Vegetais/farmacologia , Receptores Estrogênicos/metabolismo , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , Células MCF-7 , Óleos Vegetais/química , Sementes/química
20.
Mycorrhiza ; 30(5): 567-576, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535694

RESUMO

Orchid mycorrhizal fungi (OMF) are critical for seed germination and maintaining natural populations of orchids, yet the degree of specificity of most orchids to their mycorrhizal associates remains unknown. Many orchids are at risk of extinction, whether generalists or specialists, but orchid species of narrow fungal specificity are arguably under increased threat due to their requirement for specific fungal symbionts. This study characterises the fungi associated with Aerangis ellisii, a lithophytic orchid from a site in the Central Highlands of Madagascar. Culturable OMF isolated from spontaneous protocorms of this species from the wild were used for seed germination. In vitro germination and seedling development of A. ellisii were achieved with fungi derived from A. ellisii and an isolate from a different Aerangis species 30 km away. The significance of these findings and their importance to conservation strategies for this species and other Aerangis spp. is discussed. These results have important implications for the conservation of A. ellisii populations in Madagascar.


Assuntos
Micorrizas , Orchidaceae , Germinação , Madagáscar , Sementes , Simbiose
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