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1.
Artigo em Inglês | MEDLINE | ID: mdl-31610770

RESUMO

An epidemiological investigation and a retrospective case-control study were conducted into an outbreak of Salmonella Havana in alfalfa sprouts, in Adelaide, Australia. In total, 31 cases of S. Havana were notified during June and July 2018 and linked to the outbreak. Eighteen cases and 54 unmatched controls were included in a case-control study. Results from the case-control study indicated an increased risk of illness linked to the consumption of alfalfa sprouts; this was supported by trace-back, sampling and environmental investigations. This outbreak of S. Havana was caused by consumption of alfalfa sprouts from one local sprouts producer. It is unclear as to when in the production of alfalfa sprouts the contamination occurred. However, contaminated seeds and poor pest control are the most likely causes. This investigation highlights the importance of ensuring that producers take appropriate action to minimise the likelihood of contamination and to comply with legislation and standards for primary production and food safety.


Assuntos
Contaminação de Alimentos , Microbiologia de Alimentos , Medicago sativa/microbiologia , Infecções por Salmonella/epidemiologia , Salmonella enterica , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Surtos de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sementes/microbiologia , Austrália do Sul/epidemiologia , Adulto Jovem
2.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3478-3485, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602912

RESUMO

Tripterygium Glycosides Tablets has good anti-inflammatory and immunomodulatory activities,but its reproductive damage is significant. Previous studies of the research group have found that Cuscutae Semen flavonoids can improve spermatogenic cell damage caused by Tripterygium Glycosides Tablets by regulating spermatogenic cell cycle,apoptosis and related protein expression,but the mechanism of action at the gene level is still unclear. In this study,Illumina high-throughput sequencing platform was applied in transcriptional sequencing of spermatogenic cells of rats after the intervention of Cuscutae Semen flavonoids and Tripterygium Glycosides Tablets. Differentially expressed genes were screened out and the GO enrichment and KEGG pathway analysis of differentially expressed genes were conducted to explore the mechanism of Cuscutae Semen flavonoids in improving reproductive injury caused by Tripterygium Glycosides Tablets. The results showed that 794 up-regulated genes and 491 down-regulated genes were screened in Tripterygium Glycosides Tablets group compared with the blank group. Compared with Tripterygium Glycosides Tablets,440 up-regulated genes and 784 down-regulated genes were screened in the Cuscutae Semen flavonoids+Tripterygium Glycosides Tablets group. Among them,the gene closely related to reproductive function is DNMT3 L. Analysis of GO function and KEGG signaling pathway enrichment showed that the above differentially expressed genes were mainly enriched in cell,cell process,catalytic activity,binding,ovarian steroid synthesis,thyroid hormone and other functions and pathways. The thyroid hormone signaling pathway was the common enrichment pathway of the two control groups. In a word,Cuscutae Semen flavonoids has a good treatment effect on male reproductive damage caused by Tripterygium Glycosides Tablets. The mechanism may be closely related to up-regulation of DNMT3 L genes and intervention of thyroid hormone signaling pathway. At the same time,the discovery of many different genes provides valuable information for study on the mechanism of Cuscutae Semen flavonoids and Tripterygium Glycosides Tablets compatibility decreasing toxicity and increasing efficiency.


Assuntos
Cuscuta/química , Flavonoides/farmacologia , Genitália/efeitos dos fármacos , Glicosídeos/toxicidade , Tripterygium/toxicidade , Animais , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Genitália/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Ratos , Sementes/química , Transdução de Sinais , Comprimidos , Hormônios Tireóideos/genética , Transcriptoma
3.
Se Pu ; 37(11): 1193-1199, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642272

RESUMO

Eight polyphenols were separated from grape seed by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent system composed of 1-butanol-ethyl-water (1:14:15, v/v/v) and n-hexane-ethyl-water (1:10:10, v/v/v). The upper and lower phases were used as the stationary and mobile phases, respectively. A flow rate of 2.0 mL/min was employed for the separation. The apparatus was rotated at 900 r/min, and the detection wavelength was set at 280 nm. Under the selected conditions, procyanidins B1, procyanidins B2, gallic acid, epicatechin gallate, and catechin were obtained from the grape seed extracts with a purity of 98.5%, 97.2%, 98.3%, 98.9%, and 96.7%, respectively. Epicatechin, epicatechin gallate, and gallocatechin gallate were obtained by preparative high performance liquid chromatography with the purity of 99.2%, 99.3%, and 99.2%, respectively. The proposed method is simple and shows high separation efficiency, and will be of great importance for the comprehensive utilization of grape seed.


Assuntos
Extratos Vegetais/química , Polifenóis/análise , Sementes/química , Vitis/química , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente
4.
An Acad Bras Cienc ; 91(4): e20180734, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644643

RESUMO

Seed companies are looking for promising, quick and effective alternatives to determine the physiological quality of seeds. The objective of the current work was to study the efficiency of the exudate - phenolphthalein pH test to evaluate the seeds of two lots of Libidibia ferrea (Mart. ex Tul.) L. P. Queiroz var. ferrea. The statistical design for the the exudate - phenolphthalein pH test was completely randomized with four replicates of 50 seeds in a factorial design (2 x 5), two seed lots and five soaking periods (30, 60, 90, 120, and 150 minutes), respectively, using two constant temperatures (25 and 30°C). The percentage of viability and germination of the seeds did not differ in the temperatures of 25 and 30°C and in the soaking periods by the exudate - phenolphthalein pH test. Thus, it is recommended that the test be conducted for at least 30 minutes in distilled and deionized water at the constant temperature of 25 or 30°C to evaluate the vigor of the Libidibia ferrea.


Assuntos
Caesalpinia/crescimento & desenvolvimento , Germinação/fisiologia , Fenolftaleína/análise , Sementes/crescimento & desenvolvimento , Caesalpinia/fisiologia , Concentração de Íons de Hidrogênio , Controle de Qualidade , Sementes/fisiologia , Temperatura Ambiente
5.
Sheng Wu Gong Cheng Xue Bao ; 35(9): 1698-1706, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31559751

RESUMO

Yuhua91 is a new peanut variety with high oleic acid content bred by Qingdao Agricultural University. The crossing was conducted with Luhua11 as female parent and with Kainong1715, an F435-type variety with high oleic acid content as male parent. The real F1 hybrids were screened by sequencing on PCR amplification products, and those homozygotes with bb genotype in F2 populations were screened by the same sequencing method as above. The content of oleic and linoleic acid was measured on the kernels harvested from F2 single plants by near infrared ray method, and those kernels whose content of oleic was above 80%, oleic and linoleic acid ratio was above 10.0 were obtained and planted into a row, with pedigree method for subsequent selection breeding. Yuhua91 has some characters of small pod, light and obvious pod texture, 148.06 g per 100 pods, 63.31 g per 100 kernels, 75.15% shelling percentage, long elliptic seed kernel, pink seed coat, without crack, white endotesta. Its content of protein, oil, oleic acid, linoleic acid and palmitic acid was 26.57%, 52.72%, 80.40%, 2.50% and 5.57% respectively. Yuhua91 has other characters of strong seedlings, compact pod areas, and moderate resistance to leaf spot disease and bacterial wilt. Average pod yield is 215.79 kg per Mu, 15.27% higher than the control variety Huayu20. Average seed kernels yield is 157.33 kg per Mu, 21.64% higher than the control variety Huayu20. Yuhua 91 has been registered on department of agriculture in 2018, and the registration No. is GPD peanut (2018) 370210, fit for growing in Shandong Province.


Assuntos
Arachis , Ácido Oleico , Melhoramento Vegetal , Sementes
6.
Ying Yong Sheng Tai Xue Bao ; 30(9): 2955-2963, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529870

RESUMO

Light is a key factor affecting seed germination and seedling growth. In this study, seed germination and seedling growth of Cunninghamia lanceolata and Schima superba were compared under controlled conditions with five light treatments (100%, 60%, 40%, 15% and 5% of full sunlight). The results showed that light intensity significantly impacted seed germination and seedling growth of both species. With decreasing light intensity, the germination rate and germination index of C. lanceolata increased, while those of S. superba showed a trend which increased first and then decreased, with the maximum at 40% light intensity. The seedling survival rate of both species was 0 under full sunlight, while significantly decreased with decreasing light intensity from 60% to 5%. Root length, basal stem diameter and height showed a consistent trend with the change of light availability in both species. Root length significantly decreased, basal stem diameter and height increased first and then decreased with decreasing light intensity, with the minimum at 5% light intensity. With decreasing light intensity, root biomass, stem biomass, leaf biomass and total biomass of C. lanceolata seedlings declined, while high biomass accumulation of S. superba seedlings were observed in 15%-60% light intensities, and lowest at 5% light intensity. Biomass accumulation in each organ of S. superba seedlings was greater than that of C. lanceolata seedlings under the same light intensity. High stem biomass and leaf biomass, low root biomass and root to shoot ratio were a phenotypic response to low light intensity in C. lanceolata and S. superba seedlings grown under poor light condition. The growth of C. lanceolata is better under relatively high light intensity than S. superba. Whereas S. superba is moderately shade-tolerant at the seedling stage, thus is more suitable for planting under closed canopy.


Assuntos
Cunninghamia/fisiologia , Germinação/fisiologia , Plântula/crescimento & desenvolvimento , Theaceae , Sementes
7.
J Agric Food Chem ; 67(38): 10667-10677, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31483636

RESUMO

This study investigated the modulatory effects of Decaisnea insignis seed oil (DISO), which was rich in palmitoleic acid (55.25%), palmitic acid (12.25%), and oleic acid (28.74%), on alcohol-induced metabolism disorder in mice. Fifty mice were orally administered with 38% alcohol (0.4 mL/day) and without or with DISO (3, 6, and 12 g/kg) for consecutive 12 weeks. DISO inhibited the alcohol-induced weight loss and liver function abnormality (p < 0.01) and shifted the profiles of cecal microbiome: elevating the abundance of Lactobacillus, Ruminoccoceae_UCG_004 (p < 0.05) and decreasing abundance of Parabacteroides (p < 0.05). This treatment also regulated metabolome response of amino acid and lipid metabolism in cecal content: upregulating 5-hydroxyindole-3-acetic acid (p < 0.05), 6-hydroxynicotinic acid, 5-methoxytryptamine, nicotinamide, and nicotinic acid (p < 0.1) and downregulating androsterone, tryptophan, and indole-3-acetamide (p < 0.05). DISO protected against alcoholic liver injury and gut microbiota dysbiosis by enriching the relative abundance of Lactobacillus, which was positively associated with the improvement of intestinal permeability and tryptophan metabolism.


Assuntos
Álcoois/efeitos adversos , Disbiose/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Hepatopatias Alcoólicas/prevenção & controle , Magnoliopsida/química , Óleos Vegetais/administração & dosagem , Consumo de Bebidas Alcoólicas/efeitos adversos , Aminoácidos/metabolismo , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ceco/efeitos dos fármacos , Ceco/microbiologia , Disbiose/metabolismo , Disbiose/microbiologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/microbiologia , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Microbiota/efeitos dos fármacos , Sementes/química
8.
J Agric Food Chem ; 67(38): 10764-10773, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31487158

RESUMO

It has been hypothesized that the α-methylene-γ-lactone moiety of sesquiterpene lactones is a key unit for their bioactivity. As a consequence, modifications of these compounds have been focused on this fragment. In the work reported here, two sesquiterpene lactones, namely, dehydrocostuslactone and ß-cyclocostunolide, a eudesmanolide obtained by controlled cyclization of costunolide, were chosen for modification by Michael addition at C-13. On applying this reaction to both compounds, it was possible to introduce the functional groups alkoxy, amino, carbamoyl, hydroxy, and thiol to give products in good to high yields, depending on the base and solvent employed. In particular, the introduction of a thiol group at C-13 in both compounds was achieved with outstanding yields (>90%) and this is unprecedented for these sesquiterpene lactones. The bioactivities of the products were evaluated on etiolated wheat coleoptile elongation and germination of seeds of parasitic weeds, with significant activity observed on Orobanche cumana and Phelipanche ramosa. The structure-activity relationships are discussed.


Assuntos
Lactonas/química , Orobanchaceae/química , Orobanche/química , Extratos Vegetais/química , Plantas Daninhas/química , Sesquiterpenos/química , Germinação , Estrutura Molecular , Orobanchaceae/crescimento & desenvolvimento , Orobanche/crescimento & desenvolvimento , Plantas Daninhas/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento , Compostos de Sulfidrila/química
9.
J Agric Food Chem ; 67(37): 10313-10320, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31502448

RESUMO

A peptide fraction with molecular masses below 3 kDa (PSH-3 kDa) from a peach seed hydrolysate demonstrated high angiotensin converting enzyme (ACE) inhibitory activity (concentration to inhibit 50% ACE (IC50) = 16.4 µg/mL) in our previous work. This work proposes a further study of this highly active fraction. RP-HPLC enabled two fractions (F3 and F4) with high inhibitory activity (IC50 = 2.0 ± 0.5 and 1.2 ± 0.2 µg/mL, respectively) to be isolated. Peptide analysis by LC-Q-TOF-MS/MS using reverse-phase and hydrophilic interaction chromatography enabled 33 peptides within both fractions to be identified. Among them, peptide isoleucine-tyrosine-serine-proline-histidine (IYSPH) showed the highest capacity. The lack of cytotoxicity of peptides was demonstrated in three different cell lines (HeLa, HT-29, and HK-2). Oral administration of PSH-3 kDa fraction or peptide IYSPH caused a significant systolic blood pressure reduction (-30 mmHg) on spontaneously hypertensive rats after 3-6 h treatment.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Hipertensão/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Prunus persica/química , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Animais , Anti-Hipertensivos/isolamento & purificação , Pressão Sanguínea/efeitos dos fármacos , Humanos , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Masculino , Peptidil Dipeptidase A/metabolismo , Extratos Vegetais/isolamento & purificação , Hidrolisados de Proteína/química , Ratos , Ratos Endogâmicos SHR , Sementes/química
10.
An Acad Bras Cienc ; 91(3): e20180439, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531531

RESUMO

The orchid seed banks of Atlantic Forest may be considered a key strategy for the conservation of species threatened with extinction by indiscriminate collection or habitat destruction. The aim of this study was to evaluate the seed viability, to choose the best culture medium for the asymbiotic germination and evaluate germination, after storage for different periods and temperatures for the Brazilian native orchids: Gomesa praetexta (Rchb.f.) M.W.Chase & N.H.Williams, Gomesa forbesii (Hook.) M.W.Chase & N.H.Williams, Gomesa recurva R.Br. and Grandiphyllum divaricatum (Lindl.) Docha Neto. Knudson C (KC), Murashige & Skoog (MS), half-strength MS (1/2 MS macro- and micro-nutrients) and Woody Plant Medium (WPM) culture media were tested for germination. The WPM culture medium was the best for asymbiotic germination of all species evaluated, with high germination percentages and improved seedling development. Seeds of G. divaricatum, G. praetexta, G. recurva and G. forbesii indicated orthodox behavior, with high viability rates after 12 months of storage, being recommended the storage temperature of -80°C for the first three species and -20°C for G. forbesii. The protocol developed in the present study was efficient for seed bank storage, in vitro germination and seedling production of G. divaricatum and G. praetexta, contributing to conservation strategies of these species.


Assuntos
Técnicas de Cultura/métodos , Germinação/fisiologia , Orchidaceae/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Aclimatação , Brasil , Meios de Cultura , Espécies em Perigo de Extinção , Florestas , Orchidaceae/classificação , Banco de Sementes
11.
J Agric Food Chem ; 67(39): 10813-10822, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31490069

RESUMO

Traditional seed pretreatment methods cause secondary pollution for the application of various chemicals. This study investigated the effect of dielectric barrier discharge (DBD) cold plasma on seedling growth. Effects of plasma-activated tap water (PATW) and plasma-activated seeds (PAS) were compared for germination rates, seedling height, dry weight, and chlorophyll content. Results show that compared with controls these growth parameters were all increased by more than 50%. The yields and contributions of hydrogen peroxide, nitrate, nitrite, and ammonium were quantified. Hydrogen peroxide and nitrate have an important role in seedling growth. By etching, the seed epidermis free radicals can reduce the apparent contact angle and increase the water absorption of the seeds. In addition to the low cost of PATW and PAS compared with commercial fertilizers, DBD does not involve any chemical addition. Thus, both PATW and PAS can be an alternative for improvement of agricultural production.


Assuntos
Produção Agrícola/métodos , Ervilhas/efeitos dos fármacos , Gases em Plasma/farmacologia , Sementes/crescimento & desenvolvimento , Compostos de Amônio/metabolismo , Clorofila/metabolismo , Produção Agrícola/instrumentação , Germinação/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Nitratos/metabolismo , Ervilhas/química , Ervilhas/crescimento & desenvolvimento , Ervilhas/metabolismo , Gases em Plasma/química , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/química , Sementes/efeitos dos fármacos , Sementes/metabolismo , Água/química
12.
J Agric Food Chem ; 67(39): 10880-10890, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31508956

RESUMO

A sustainable biomass-based nanocomposite hydrogel was formulated, characterized, and applied for curcumin delivery. Phytosynthesized zinc oxide nanoparticles (ZnO NPs) employing musk melon (Cucumis melo) seed extract was embedded in the hydrogel matrices and cross-linked using Dialdehyde cellulose prepared from sugarcane (Saccharum officinarum) bagasse (SCB). Nanoparticle incorporation enhanced the hydrogel's swelling degree to 4048% at pH 4.0. Also, an improved tensile strength of 14.1 ± 0.32 MPa was exhibited by the nanocomposite hydrogel compared to 9.79 ± 0.76 MPa for the pure chitosan cellulose hydrogel. A curcumin loading efficiency of 89.68% with around 30% increased loading was exhibited for the nanocomposite hydrogel. A Fickian diffusion-controlled curcumin release mechanism with maximum release at pH 7.4 was obtained. The synergistic effect on the antimicrobial activity was exhibited against Staphylococcus aureus and Trichophyton rubrum. The in vitro cytotoxicity studies employing L929 cells and A431 cells demonstrated good biocompatibility and enhanced anticancer activity of the curcumin-loaded green nanocomposite hydrogel compared to pure curcumin.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Curcumina/química , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Celulose/química , Quitosana/química , Cucumis melo/química , Portadores de Fármacos/química , Hidrogéis/química , Nanocompostos/química , Nanopartículas/química , Sementes/química , Staphylococcus aureus/efeitos dos fármacos , Trichophyton/efeitos dos fármacos , Trichophyton/crescimento & desenvolvimento , Óxido de Zinco/química
13.
J Agric Food Chem ; 67(40): 11262-11276, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31509416

RESUMO

Tartary buckwheat (Fagopyrum tataricum) seeds are rich in flavonoids. However, the detailed flavonoid compositions and the molecular basis of flavonoid biosynthesis in tartary buckwheat seeds remain largely unclear. Here, we performed a combined metabolite profiling and transcriptome analysis to identify flavonoid compositions and characterize genes involved in flavonoid biosynthesis in the developing tartary buckwheat seeds. In total, 234 flavonoids, including 10 isoflavones, were identified. Of these, 80 flavonoids were significantly differential accumulation during seed development. Transcriptome analysis indicated that most structural genes and some potential regulatory genes of flavonoid biosynthesis were significantly differentially expressed in the course of seed development. Correlation analysis between transcriptome and metabolite profiling shown that the expression patterns of some differentially expressed structural genes and regulatory genes were more consistent with the changes in flavonoids profiles during seed development and promoted one SG7 subgroup R2R3-MYB transcription factors (FtPinG0009153900.01) was identified as the key regulatory gene of flavonoid biosynthesis. These findings provide valuable information for understanding the mechanism of flavonoid biosynthesis in tartary buckwheat seeds and the further development of tartary buckwheat health products.


Assuntos
Fagopyrum/metabolismo , Flavonoides/biossíntese , Proteínas de Plantas/genética , Sementes/crescimento & desenvolvimento , Fagopyrum/química , Fagopyrum/genética , Fagopyrum/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/metabolismo , Plantas/classificação , Plantas/genética , Plantas/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
14.
BMC Ecol ; 19(1): 41, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533695

RESUMO

BACKGROUND: Understanding how traditional agriculture systems have been maintained would help design sustainable agriculture. In this study, we examined how farmers have used two types of local trees (Torreya grandis) for stable yield and maintaining genetic diversity in the "globally important agricultural heritage torreya tree system". The two type of torreya trees are grafted torreya (GT) tree and non-grafted-torreya (NGT) tree. The GT tree has only female and was used to produced seed yields. The NGT tree has both male and female and was used to support GT tree by providing pollens and rootstocks. We first tested the ratio of GT tree to NGT tree, their age groups, ratio of female trees (including GT and NGT trees) to male, and the flowering period of GT and NGT trees. We then tested seed yields and genetic diversity of GT and NGT trees. We further tested gene flow among NGT trees, and the relationship of gene flow with exchange rates of pollens and seeds. RESULTS: GT and NGT trees (male and female) were planted in a mosaic pattern with a ratio of 4:1 (GT:NGT). In this planting pattern, one NGT male trees provided pollen for 20 female trees of GT and NGT. The trees were classified into four age groups (I = 100-400 years old; II = 400-700 years old; III = 700-1000 years old; and IV = 1000-1300 years old) based on basal diameter. The entire flowering period was longer for NGT trees than for GT trees that ensured GT trees (which lack of males) being exposed to pollens. GT tree had high and stable seed yield that increased with age groups. High genetic diversity has been maintained in both rootstocks of the GT trees and NGT trees. There was a strong gene flow among NGT trees, which positive correlated with the exchange rates of pollens and seeds. CONCLUSIONS: Our results suggest that farmers obtain stable seed yields, and maintain high genetic diversity by ingeniously using the local GT tree as yield producer and NGT tree as supporter. These GT and NGT trees together ensure sustainable torreya production.


Assuntos
Taxaceae , Árvores , Agricultura , Feminino , Fluxo Gênico , Variação Genética , Masculino , Sementes
15.
Chemosphere ; 235: 1066-1072, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561296

RESUMO

This study was conducted to explore the effects of priming of seven-year-old aged seeds with different concentrations of silver nanoparticles (AgNPs) on growth of broad bean (Vicia faba L.). Seeds were primed with different concentrations of AgNPs for 6 h before growing in the plastic trays. Different growth parameters like growth attributes, photosynthetic pigments, carbohydrates, antioxidant enzymes and chloroplast ultrastructure were estimated after 14 days of germination. Priming with AgNPs affected the root and shoot growth attributes as compared with control depending upon concentrations of AgNPs. In all treatments, photosynthetic pigments increased significantly above control levels, but total soluble sugars decreased in 10 and 50 ppm AgNPs and slightly increased in 100 ppm AgNPs as compared with control. Starch accumulation was apparent in all treated seedlings above that of control levels. Mesophyll cells of all treated seedlings were altered with electron dense particles than control. Priming with AgNPs affected the chloroplast structure which appeared in the form of less stacking of Greene, formation of protrusions and extensions, irregular shape of chloroplasts as compared with spindle shaped regular chloroplasts of control. In all treatments, total phenols were slightly affected as compared with control. The antioxidant enzyme activities in seedlings varied with the dose and type of antioxidants. Overall, AgNPs adversely affected the chloroplast ultrastructure, but increased growth of seedlings and starch accumulation. Further studies are required to explore the effects of AgNPs on the long-term on crop productivity of aged seeds.


Assuntos
Cloroplastos/efeitos dos fármacos , Nanopartículas Metálicas/química , Plântula/ultraestrutura , Prata/química , Antioxidantes/farmacologia , Cloroplastos/ultraestrutura , Germinação/efeitos dos fármacos , Fotossíntese , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Prata/farmacologia , Amido/metabolismo , Vicia faba/crescimento & desenvolvimento , Vicia faba/ultraestrutura
16.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2249-2256, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418227

RESUMO

Disturbance is the driving force of forest succession, which can change forest structure and surface vegetation. Disturbance also affects rodent-mediated seed dispersal. In this study, numbered plastic tags were used to examine the responses of rodent dispersal behavior to the fates of Quercus aliena var. acuteserrata acorns at three habitats formed by different artificial disturbances in pine-oak mixed forests in the Qinling Mountains, i.e., unlogged stand, stand in the third year after tending thinning, and bare land. The results showed that seed removal rate from stands in the third year after tending was significantly higher than that in the other two habitats. The proportion of predation in bare land was significantly lower than that in the unlogged stand (25.0%) and in the stand in the third year after tending thinning (36.3%). In the third year after tending thinning, the seed predation rate after seed moving was significantly higher than those in the unlogged stand (17.3%) and bare land (5.0%). Moreover, the proportion of scatter hoarding after removal was also highest in the stand in the third year after tending thinning (4.3%). The longest average dispersal distance (26 m) occurred in the stand in the third year after tending thinning, which was significantly longer than those at the other two habitats. Therefore, the different habitat types significantly influenced the initial seed dispersal process by rodents, with consequences on the rates of seedling establishment. Habitat types affected the foraging strategies of rodents, thereby leading to different seed dispersal modes and natural regeneration patterns in the forest.


Assuntos
Ecossistema , Quercus/fisiologia , Roedores , Dispersão de Sementes , Animais , Florestas , Sementes
17.
Oecologia ; 191(1): 165-175, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31372894

RESUMO

Alternative vegetation types that switch from one to another under contrasting fire regimes are termed fire-mediated alternative stable states (FMASS). Typically, pyrophylic communities (i.e., vegetation assemblages favored by burning) dominate under high frequencies or intensities of fire. Conversely, fire-sensitive (pyrophobic) vegetation types persist under long fire-free conditions. As the persistence traits of plants of FMASS systems are generally poorly researched, threshold levels of pyric disturbance that trigger 'state-switching' are often unknown. Dense thickets of the obligate-seeder shrub waputi (Aluta maisonneuvei ssp. maisonneuvei [Myrtaceae]) form fire-retarding woody islands within highly flammable spinifex (Triodia spp.) grasslands in arid Australia. To examine the tolerance of Aluta thickets to burning, we investigated: (1) the influence of post-fire rainfall and fire severity on recruitment (a field study); (2) soil seedbank densities (a field study); and (3) fire-related dormancy cues in seeds (a germination trial). We found a positive relationship between recruitment and post-fire rainfall volume, and much higher mean recruitment at sites with high- (5.9 seedlings/m2) than low-severity-burnt (2.2 seedlings/m2) and unburnt shrubs (0.03 seedlings/m2). Post-fire regeneration was mediated by dense soil-borne seedbanks, and the germination trial indicated that smoke promoted germination. Although Aluta shrubs are invariably fire-killed, high-severity fires are unlikely to lead to state shifts from shrubland to grassland because of the ability of mature stands to regenerate from dense, fire-cued seedbanks. Nevertheless, given that Aluta seedlings are exceptionally slow-growing, post-fire droughts combined with fire-return intervals less than the Aluta primary juvenile period of c. 5 years could drive conversion from Aluta- to Triodia-dominated vegetation.


Assuntos
Fogo , Austrália , Germinação , Sementes , Austrália Ocidental
18.
Oecologia ; 191(2): 369-375, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31428868

RESUMO

Despite being central concepts for life history theory, little is known about how reproductive effort and costs vary with individual age once plants have started to reproduce. We conducted a 5-year field study and estimated age-dependent reproductive effort for both sexes in the extraordinarily long-lived dioecious plant Borderea pyrenaica. We also evaluated costs of reproduction on vital rates for male and female plants, both by examining effects of differences in individual reproductive effort under natural conditions, and by conducting a flower removal experiment, aimed at decreasing reproductive effort. Reproductive effort was fairly constant and independent of age for males, which may reflect a strategy of adjusting overall reproductive output by spreading reproduction over the life course. Females had a higher total effort, which first increased and then decreased with age. The latter may be a response to an increasing reproductive value-an inverse of a terminal investment-or a sign of reproductive senescence due to an age-related physiological decline. Seed production was lower in plants with higher previous reproductive effort and this effect increased with age. We found no evidence for costs of reproduction on other vital rates for either sex. Experimental flower removal only resulted in progressively more negative effects on flower production in older male plants, whereas female vital rates were unaffected. Overall, this study demonstrates that not only sex, but also age influences resource allocation trade-offs and, thus, plant life history evolution.


Assuntos
Flores , Reprodução , Feminino , Masculino , Sementes
19.
Plant Dis ; 103(10): 2498-2504, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31453746

RESUMO

Downy mildew is a yield-limiting disease of sunflower, caused by the pathogen Plasmopara halstedii. Zoospore infection of root tissue shortly after planting results in systemic infection, causing postemergence damping off or severe stunting and head sterility. Although fungicide-applied seed treatments can be an effective management tool, the pathogen is resistant to phenylamide fungicides in many growing regions, and other available fungicides have limited efficacy. Oxathiapiprolin, the first member of the piperidinyl thiazole isoxazoline fungicides, was evaluated for efficacy on downy mildew in field trials conducted from 2011 to 2015 in North Dakota. Throughout the course of the study, the rate range was narrowed from active ingredient (a.i.) at 0.45 to 116.0 µg a.i. seed-1 to an optimal effective rate of 9.37 to 18.75 µg a.i. seed-1. Within that optimal range, the downy mildew incidence of sunflower planted with oxathiapiprolin-treated seed was significantly lower than the incidence in the nontreated sunflower in all 11 trials with disease pressure. Additionally, downy mildew incidence of sunflower planted with oxathiapiprolin-treated seed was significantly lower than sunflower planted with competitive commercially available fungicide-treated seed in 10 of those 11 trials. The use of oxathiapiprolin by sunflower growers is likely to reduce disease incidence and subsequent yield loss to downy mildew.


Assuntos
Helianthus , Hidrocarbonetos Fluorados , Oomicetos , Doenças das Plantas , Pirazóis , Antiparasitários/farmacologia , Helianthus/parasitologia , Hidrocarbonetos Fluorados/farmacologia , North Dakota , Oomicetos/efeitos dos fármacos , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Pirazóis/farmacologia , Sementes/química
20.
J Agric Food Chem ; 67(37): 10306-10312, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31464431

RESUMO

Conjugated linolenic acids (CLnAs) are natural phytochemicals with known and potential bioactivities in mammals. Established CLnA sources are limited to a few common fruit seeds, notably pomegranate seeds and cherry pits, and the search for alternatives is impeded in part by cumbersome methods for reliable measurement. We investigated CLnA contents in lower value fruit seeds with a recently available facile mass spectrometry method, solvent-mediated chemical ionization, enabling and quantitative analysis. We report for the first time the detection of CLnAs in cantaloupe and honeydew seeds at levels of 2 mg CLnA/g seed kernel. Based on the combined waste stream for these muskmelons of about 1.4 billion pounds in the USA annually, we estimate that the available CLnAs amount to 37.5 tons, similar to cherry pits. Our results suggest the potentially enhanced economic value of a specific class of bioactives that may be extracted from discarded food processing waste.


Assuntos
Cucurbitaceae/química , Ácidos Linoleicos Conjugados/análise , Extratos Vegetais/análise , Sementes/química , Resíduos/análise , Ácidos Linoleicos Conjugados/isolamento & purificação , Espectrometria de Massas , Extratos Vegetais/isolamento & purificação
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