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1.
Ecol Evol ; 14(5): e11462, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38799389

RESUMEN

Alocasia sakonakhonensis Chatan & Promprom (Araceae), a new species from northeastern Thailand, is described and illustrated. It is clearly different from other previously known species by leaves, spathe, ovary, sterile interstice, synandria, and appendix. Color illustrations, and a distribution map are provided, as well as comparative morphological characters about its similar species. The preliminary conservation status assessment of the new species was presented.

2.
Adv Virus Res ; 118: 213-272, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38461030

RESUMEN

Grapevine leafroll-associated virus 3 (GLRaV-3) is a major pathogen of grapevines worldwide resulting in grapevine leafroll disease (GLD), reduced fruit yield, berry quality and vineyard profitability. Being graft transmissible, GLRaV-3 is also transmitted between grapevines by multiple hemipteran insects (mealybugs and soft scale insects). Over the past 20 years, New Zealand has developed and utilized integrated pest management (IPM) solutions that have slowly transitioned to an ecosystem-based biological response to GLD. These IPM solutions and combinations are based on a wealth of research within the temperate climates of New Zealand's nation-wide grape production. To provide context, the grapevine viruses present in the national vineyard estate and how these have been identified are described; the most pathogenic and destructive of these is GLRaV-3. We provide an overview of research on GLRaV-3 genotypes and biology within grapevines and describe the progressive development of GLRaV-3/GLD diagnostics based on molecular, serological, visual, and sensor-based technologies. Research on the ecology and control of the mealybugs Pseudococcus calceolariae and P. longispinus, the main insect vectors of GLRaV-3 in New Zealand, is described together with the implications of mealybug biological control agents and prospects to enhance their abundance and/or fitness in the vineyard. Virus transmission by mealybugs is described, with emphasis on understanding the interactions between GLRaV-3, vectors, and plants (grapevines, alternative hosts, or non-hosts of the virus). Disease management through grapevine removal and the economic influence of different removal strategies is detailed. Overall, the review summarizes research by an interdisciplinary team working in close association with the national industry body, New Zealand Winegrowers. Teamwork and communication across the whole industry has enabled implementation of research for the management of GLD.


Asunto(s)
Closteroviridae , Hemípteros , Vitis , Animales , Ecosistema , Nueva Zelanda , Enfermedades de las Plantas , Biología
3.
Plant Divers ; 45(5): 491-500, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37936816

RESUMEN

Beta diversity (ß-diversity) is the scalar between local (α) and regional (γ) diversity. Understanding geographic patterns of ß-diversity is central to ecology, biogeography, and conservation biology. A full understanding of the origin and maintenance of geographic patterns of ß-diversity requires exploring both taxonomic and phylogenetic ß-diversity, as well as their respective turnover and nestedness components, and exploring phylogenetic ß-diversity at different evolutionary depths. In this study, we explore and map geographic patterns of ß-diversity for angiosperm genera in regional floras across the world. We examine both taxonomic and phylogenetic ß-diversity and their constituent components, and both tip-weighted and basal-weighted phylogenetic ß-diversity, and relate them to latitude. On the one hand, our study found that the global distribution of ß-diversity is highly heterogeneous. This is the case for both taxonomic and phylogenetic ß-diversity, and for both tip-weighted and basal-weighted phylogenetic ß-diversity. On the other hand, our study found that there are highly consistent geographic patterns among different metrics of ß-diversity. In most cases, metrics of ß-diversity are negatively associated with latitude, particularly in the Northern Hemisphere. Different metrics of taxonomic ß-diversity are strongly and positively correlated with their counterparts of phylogenetic ß-diversity.

4.
R Soc Open Sci ; 10(11): 231093, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38026041

RESUMEN

Pollinator diversity and abundance are declining globally. Cropland agriculture and the corresponding use of agricultural pesticides may contribute to these declines, while increased pollinator habitat (flowering plants) can help mitigate them. Here we tested whether the relative effect of wildflower plantings on pollinator diversity and counts were modified by proportion of nearby agricultural land cover and pesticide exposure in 24 conserved grasslands in Iowa, USA. Compared with general grassland conservation practices, wildflower plantings led to only a 5% increase in pollinator diversity and no change in counts regardless of the proportion of cropland agriculture within a 1 km radius. Pollinator diversity increased earlier in the growing season and with per cent flower cover. Unexpectedly, neither insecticide nor total pesticide concentrations on above-ground passive samplers were related to pollinator diversity. However, pollinator community composition was most strongly related to date of sampling, total pesticide concentration, and forb or flower cover. Our results indicate very little difference in pollinator diversity between grassland conservation practices with and without wildflower plantings. Given the relatively high economic costs of wildflower plantings, our research provides initial evidence that investment in general grassland conservation may efficiently conserve pollinator diversity in temperate regions of intensive cropland agriculture.

5.
Genome Biol Evol ; 15(4)2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-36951086

RESUMEN

Eukaryotes maintain separate protein translation systems for nuclear and organellar genes, including distinct sets of tRNAs and aminoacyl-tRNA synthetases (aaRSs). In animals, mitochondrial-targeted aaRSs are expressed at lower levels and are less conserved in sequence than cytosolic aaRSs involved in translation of nuclear mRNAs, likely reflecting lower translational demands in mitochondria. In plants, translation is further complicated by the presence of plastids, which share most aaRSs with mitochondria. In addition, plant mitochondrial tRNA pools have a dynamic history of gene loss and functional replacement by tRNAs from other compartments. To investigate the consequences of these distinctive features of translation in plants, we analyzed sequence evolution in angiosperm aaRSs. In contrast to previously studied eukaryotic systems, we found that plant organellar and cytosolic aaRSs exhibit only a small difference in expression levels, and organellar aaRSs are slightly more conserved than cytosolic aaRSs. We hypothesize that these patterns result from high translational demands associated with photosynthesis in mature chloroplasts. We also investigated aaRS evolution in Sileneae, an angiosperm lineage with extensive mitochondrial tRNA replacement and aaRS retargeting. We predicted positive selection for changes in aaRS sequence resulting from these recent changes in subcellular localization and tRNA substrates but found little evidence for accelerated sequence divergence. Overall, the complex tripartite translation system in plant cells appears to have imposed more constraints on the long-term evolutionary rates of organellar aaRSs compared with other eukaryotic lineages, and plant aaRS protein sequences appear largely robust to more recent perturbations in subcellular localization and tRNA interactions.


Asunto(s)
Aminoacil-ARNt Sintetasas , Animales , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Células Vegetales/metabolismo , Secuencia de Aminoácidos , Citosol/metabolismo , ARN de Transferencia/genética , ARN de Transferencia/metabolismo
6.
Biomolecules ; 13(2)2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36830580

RESUMEN

In the sexual reproduction of flowering plants, two independent fertilization events occur almost simultaneously: two identical sperm cells fuse with either the egg cell or the central cell, resulting in embryo and endosperm development to produce a seed. GCS1/HAP2 is a sperm cell membrane protein essential for plasma membrane fusion with both female gametes. Other sperm membrane proteins, DMP8 and DMP9, are more important for egg cell fertilization than that of the central cell, suggesting its regulatory mechanism in GCS1/HAP2-driving gamete membrane fusion. To assess the GCS1/HAP2 regulatory cascade in the double fertilization system of flowering plants, we produced Arabidopsis transgenic lines expressing different GCS1/HAP2 variants and evaluated the fertilization in vivo. The fertilization pattern observed in GCS1_RNAi transgenic plants implied that sperm cells over the amount of GCS1/HAP2 required for fusion on their surface could facilitate membrane fusion with both female gametes. The cytological analysis of the dmp8dmp9 sperm cell arrested alone in an embryo sac supported GCS1/HAP2 distribution on the sperm surface. Furthermore, the fertilization failures with both female gametes were caused by GCS1/HAP2 secretion from the egg cell. These results provided a possible scenario of GCS1/HAP2 regulation, showing a potential scheme for capturing additional GCS1/HAP2-interacting proteins.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Semillas/metabolismo , Células Germinativas/metabolismo , Fertilización , Proteínas Portadoras/metabolismo
7.
Environ Res ; 223: 115466, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36773637

RESUMEN

Formaldehyde can cause leukemia and nasopharyngeal cancer in humans, and is a major indoor air pollutant. In this study, to improve the ability of flowering plants to purify formaldehyde, we cloned the CcFALDH gene encoding formaldehyde dehydrogenase (FALDH) from the spider plant (Chlorophytum comosum), which encodes 379 amino acids with the alcohol dehydrogenase (ADH) structural domain, and used it to transform the flowering plant gloxinia (Sinningia speciosa). The FALDH activity of transgenic gloxinia was 1.8-2.7 times that of wild-type (WT) with a considerable increase in formaldehyde stress tolerance. The activities of the antioxidant enzymes SOD, POD, and CAT of transgenic gloxinia were 1.5-2.0 times those of the WT under formaldehyde stress; H2O2, O2-, and MDA contents were markedly lower than those in WT. Liquid formaldehyde and gaseous formaldehyde were metabolized at 2.1-2.8 and 2.1-2.7 times higher rates in transgenic gloxinia than in WT. Our findings indicate that overexpression of CcFALDH can enhance the capacity of flowering plants to metabolize formaldehyde, which provides a new strategy to tackle the indoor formaldehyde pollution problem.


Asunto(s)
Peróxido de Hidrógeno , Neoplasias Nasofaríngeas , Humanos , Antioxidantes/metabolismo , Formaldehído , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Magnoliopsida , Glutatión Reductasa/metabolismo
8.
Front Pharmacol ; 14: 1287793, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38333226

RESUMEN

Despite its millennial existence and empirical documentation, the ethnological knowledge of herbs is a more recent phenomenon. The knowledge of their historical uses as food, medicine, source of income and small-scale businesses, and the sociological impacts are threatened due to the slow ethnobotanical research drive. Species of the genus Solanum have long been extensively used in folk medicine to treat various illnesses of humans since the dawn of civilization. All data were systematically obtained from papers, monographs, and books written in Uzbek, Russian, and English through various scientific online databases, including Google, Google Scholar, PubMed, Scopus, Semantic Scholar, Science Direct, and Web of Science using specific keywords focused on eight Solanum species. Eight native and non-native Solanum species as S. dulcamara L., S. lycopersicum L., S. melongena L., S. nigrum L., S. rostratum Dunal., S. sisymbriifolium Lam., S. tuberosum L., and S. villosum Mill. have been recorded in Uzbekistan of Central Asia. In this article we presented recently obtained data on the diversity, morphological characteristics, global distribution, habitat, population status, phenology, reproduction, pharmacology and phytochemistry of these Solanum species in Uzbekistan. Furthermore, relying on a combination of literature reviews and analyses from various scientific papers, we focus on food consumption coupled with global ethnobotanical and ethnopharmacological uses in human diseases of the Solanum species growing in Uzbekistan. Since the dawn of civilization, these eight cultivated and non-cultivated species of Solanum have provided sustainable resources of medicinal plants in Uzbekistan to prevent and treat various human diseases. Based on the collected data, it was shown that Solanum species have not been studied ethnobotanically and ethnomedicinally in Uzbekistan and it is necessary to conduct phytochemical and biotechnological research on them in the future. Traditional uses and scientific evaluation of Solanum indicate that S. nigrum, S. sisymbriifolium and S. tuberosum are one of the most widely used species in some parts of the world. Although considerable progress has been made to comprehend the chemical and biological properties of S. nigrum and S. tuberosum species, more research on the pharmacology and toxicology of these species is needed to ensure the safety, efficacy, and quality of their biologically active extracts and isolated bioactive compounds. Additionally, conducting additional research on the structure-activity relationship of certain isolated phytochemicals has the potential to enhance their biological efficacy and advance the scientific utilization of traditional applications of Solanum taxa.

9.
Ecol Lett ; 25(10): 2177-2188, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35953880

RESUMEN

Why sex has evolved and is maintained is an open question in evolutionary biology. The Red Queen hypothesis predicts that host lineages subjected to more intense parasite pressure should invest more in sexual reproduction to continuously create novel defences against their rapidly evolving natural enemies. In this comparative study across the angiosperms, we show that hermaphrodite plant species associated with higher species richness of insect herbivores evolved flowers with higher biomass allocation towards the male sex, an indication of their greater outcrossing effort. This pattern remained robust after controlling for key vegetative, reproductive and biogeographical traits, suggesting that long-term herbivory pressure is a key factor driving the selfing-outcrossing gradient of higher plants. Although flower evolution is frequently associated with mutualistic pollinators, our findings support the Red Queen hypothesis and suggest that insect herbivores drive the sexual strategies of flowering plants and their genetic diversity.


Asunto(s)
Herbivoria , Magnoliopsida , Animales , Flores , Insectos , Polinización , Reproducción
10.
Int J Mol Sci ; 23(8)2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35457091

RESUMEN

Plant cell wall proteins (CWPs) play critical roles during plant development and in response to stresses. Proteomics has revealed their great diversity. With nearly 1000 identified CWPs, the Arabidopsis thaliana cell wall proteome is the best described to date and it covers the main plant organs and cell suspension cultures. Other monocot and dicot plants have been studied as well as bryophytes, such as Physcomitrella patens and Marchantia polymorpha. Although these proteomes were obtained using various flowcharts, they can be searched for the presence of members of a given protein family. Thereby, a core cell wall proteome which does not pretend to be exhaustive, yet could be defined. It comprises: (i) glycoside hydrolases and pectin methyl esterases, (ii) class III peroxidases, (iii) Asp, Ser and Cys proteases, (iv) non-specific lipid transfer proteins, (v) fasciclin arabinogalactan proteins, (vi) purple acid phosphatases and (vii) thaumatins. All the conserved CWP families could represent a set of house-keeping CWPs critical for either the maintenance of the basic cell wall functions, allowing immediate response to environmental stresses or both. Besides, the presence of non-canonical proteins devoid of a predicted signal peptide in cell wall proteomes is discussed in relation to the possible existence of alternative secretion pathways.


Asunto(s)
Arabidopsis , Bryopsida , Arabidopsis/metabolismo , Bryopsida/metabolismo , Pared Celular/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteoma/metabolismo , Proteómica
11.
Sci Total Environ ; 829: 154450, 2022 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-35276144

RESUMEN

Bees are exposed to various stressors, including pesticides and lack of flowering resources. Despite potential interactions between these stressors, the impacts of pesticides on bees are generally assumed to be consistent across bee-attractive crops, and regulatory risk assessments of pesticides neglect interactions with flowering resources. Furthermore, impacts of fungicides on bees are rarely examined in peer-reviewed studies, although these are often the pesticides that bees are most exposed to. In a full-factorial semi-field experiment with 39 large flight cages, we assessed the single and combined impacts of the globally used azoxystrobin-based fungicide Amistar® and three types of flowering resources (Phacelia, buckwheat, and a floral mix) on Bombus terrestris colonies. Although Amistar is classified as bee-safe, Amistar exposure through Phacelia monocultures reduced adult worker body mass and colony growth (including a 55% decline in workers and an 88% decline in males), while the fungicide had no impact on colonies in buckwheat or the floral mix cages. Furthermore, buckwheat monocultures hampered survival and fecundity irrespective of fungicide exposure. This shows that bumblebees require access to complementary flowering species to gain both fitness and fungicide tolerance and that Amistar impacts are flowering resource-dependent. Our findings call for further research on how different flowering plants affect bees and their pesticide tolerance to improve guidelines for regulatory pesticide risk assessments and inform the choice of plants that are cultivated to safeguard pollinators.


Asunto(s)
Fungicidas Industriales , Insecticidas , Plaguicidas , Animales , Abejas , Productos Agrícolas , Fungicidas Industriales/toxicidad , Masculino , Reproducción
12.
Ying Yong Sheng Tai Xue Bao ; 33(2): 527-536, 2022 Feb.
Artículo en Chino | MEDLINE | ID: mdl-35229527

RESUMEN

Pollinators provide important ecosystem services for crop production and food security. With the development of agricultural economy and the increasing intensity of land-use, a large number of natural or semi-natural habitats have been converted to croplands. Landscape homogenization and intensive management lead to the decline of wild bee diversity and threaten the sustainable agricultural production. In this study, we investigated the effects of landscape complexity (proportion of semi-natural habitats), local management practices (local flowering plant diversity and soil total nitrogen), and their interactions on diversity of bee pollinators in apple orchard in Changping District, Beijing. A total of 8642 bee individuals were captured, including 5125 honey bees and 3517 wild bees from 5 families, 14 genera, and 49 species. The optimal landscape scale for the response of bee diversity to landscape complexity and local management intensity was 500 m. Within 500 m radius of the site, the abundance of overall bees and wild bees significantly increased with increasing proportion of semi-natural habitats. The landscape complexity interacting with local flowering plant diversity significantly affected the richness of overall bee and wild bee. When the proportion of semi-natural habitats surrounding the apple orchards was low (≤29.9%), we found a positive effect of flowering plant diversity on the richness of overall bee and wild bee, whereas a reversed trend was found when the proportion of semi-natural habitats surrounding the apple orchards was high (>29.9%). In addition, the abundance of honey bees significantly increased with the increase of local flowering plant diversity and soil total nitrogen. The soil total nitrogen interacting with local flowering plant diversity significantly affected the honey bee abundance. At low levels of soil total nitrogen (≤1.9 g·kg-1), there was a positive effect of flowering plant diversity on honey bee abundance; whereas this trend was reversed at high levels of soil total nitrogen (>1.9 g·kg-1). Increasing the proportion of semi-natural habitats in agricultural landscape was beneficial to the increase of wild bee abundance, and flowering plant diversity could promote bee diversity but depending on landscape scale (proportion of semi-natural habitats) and local scale (nitrogen application). Therefore, multi-scale factors should be considered to develop conservation strategies to maintain the diversity of wild bees in agricultural landscape. Maintaining a higher proportion of cultivated land as much as possible is still a long-term requirement for production, while maintaining intermediate landscape complexity, increasing the diversity of flowering plants on the ground, and reducing the application of nitrogen fertilizer would be effective ways to promote the diversity of pollinating bees in apple orchards.


Asunto(s)
Malus , Polinización , Agricultura , Animales , Abejas , Beijing , Ecosistema , Polinización/fisiología
13.
Ecol Evol ; 12(2): e8544, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35154648

RESUMEN

We aim to assess the influence of phylogenetic scale on the relationships of taxonomic and phylogenetic turnovers with environment for angiosperms in China. Specifically, we quantify the effects of contemporary climate on ß-diversity at different phylogenetic scales representing different evolutionary depths of angiosperms. We sampled a latitudinal gradient and a longitudinal gradient of angiosperm assemblages across China (each ≥3400 km). Species composition in each assemblage was documented. Three metrics of ß-diversity (ßsim.tax measuring taxonomic ß-diversity; ßsim.phy and Dpw measuring tip- and basal-weighted phylogenetic ß-diversity, respectively) were quantified among assemblages at sequential depths in the evolutionary history of angiosperms from the tips to deeper branches. This was done by slicing the angiosperm phylogenetic tree at six evolutionary depths (0, 15, 30, 45, 60, and 75 million years ago). ß-diversity at each evolutionary depth was related to geographic and climatic distances between assemblages. In general, the relationship between ß-diversity and climatic distance decreased from shallow to deep evolutionary time slice for all the three metrics. The slopes of the decreasing trends for ßsim.tax and ßsim.phy were much steeper for the latitudinal gradient than for the longitudinal gradient. The decreasing trend of the strength of the relationship was monotonic in all cases except for Dpw across the longitudinal gradient. Geographic distance between assemblages explained little variation in ß-diversity that was not explained by climatic distance. Our study shows that the strength of the relationship between ß-diversity and climatic distance decreases conspicuously from shallow to deep evolutionary depth for the latitudinal gradient, but this decreasing trend is less steep for the longitudinal gradient than for the latitudinal gradient, which likely reflects the influence of historical processes (e.g., the collision of the Indian plate with the Eurasian plate) on ß-diversity.

14.
J Econ Entomol ; 114(3): 1128-1137, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-33834196

RESUMEN

Increasing the biodiversity of agroecosystems can increase populations of natural enemies that are useful for pest control. Orchards often have a low diversity of plant species, which is not conducive to maintaining ecosystem functions and services. However, additional flowering plants could provide natural enemies with beneficial resources. To assess the ability of flowering plants to attract predators and increase the biological control of Aphis spiraecola Patch, we established individual plots of three different flowering plant species with sequential bloom periods between the rows of apple orchard. These plants attracted predators such as Coccinellidae, Syrphidae, and Chrysopidae when flowering. The density of predators on trees in the three flowering plant plots was significantly higher than that in the control, whereas the density of aphids on trees in Orychophragmus violaceus (L.) O. E. Schulz (Rhoeadales: Brassicaceae) and Cnidium monnieri (Linn.) Cuss. (Apiales: Apiaceae) plots were significantly lower than that in control. The density of aphids on trees in Calendula officinalis L. (Asterales: Asteraceae) plots was significantly lower than in other plots at second peak period. There was a significant negative correlation between the population of aphids and predators on trees at peak of aphids. Cage exclusion tests showed that the biocontrol services index (BSI) of O. violaceus was highest (32.7%) on 24 May, and the BSI of C. monnieri was highest (47.6%) on 7 June. Our results suggest that the temporal combination of different flowering plants could provide useful effective biocontrol to management pest in orchard.


Asunto(s)
Áfidos , Magnoliopsida , Malus , Animales , Ecosistema , Control Biológico de Vectores
15.
Environ Entomol ; 50(4): 842-851, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-33851702

RESUMEN

Insecticide overuse in crop production systems often results in detrimental effects on predators and parasitoids, which regulate important insect pests. The natural enemies are also unable to survive in monocrop landscapes with the absence of shelter or food sources. Diversified vegetation, especially with flowering plants, can enhance natural enemy abundance and diversity, thus strengthening biological control, enabling farmers to reduce insecticides. In this study, we conserved bund vegetation and manipulated the existing rice landscapes with flowering plants to provide food and shelter for the biological control agents. Our study revealed significant positive relationships between predator densities and bund plant diversity. The abundance of predators significantly increased in the eco-engineered plots, especially at the flowering peaks compared to the insecticide-treated and control plots, while parasitoids were more diverse in both the eco-engineered and control plots. There were no significant differences in planthopper and leafhopper densities among the treatments during the rice early and maximum tillering stages, suggesting effective natural control of these herbivore pests in the eco-engineered plots at the early rice-growing season. However, at the heading stage relatively higher planthopper and leafhopper populations in the control and eco-engineered plots than in the insecticide-sprayed plots were recorded, suggesting perhaps the need for insecticide interventions if exceeding the threshold at this time. Our study indicates that manipulating the habitats surrounding the rice fields to enhance natural enemies is a sustainable practice in rice production as it can enhance the natural suppression of pests and thus reducing the need for insecticide.


Asunto(s)
Magnoliopsida , Oryza , Animales , Insectos , Control Biológico de Vectores , Estaciones del Año
16.
Ecol Evol ; 11(24): 18434-18445, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35003682

RESUMEN

Floral plantings are often used in agriculture to attract pollinator communities, but they also play an important role in recruiting and establishing natural communities for natural pest control. Inconsistent effects of floral plantings for pest control may be a result of an absence of mechanistic insights and a reliance on the idea that simply increasing flower diversity will benefit these services. A more tailored set of flower species may be needed to benefit the natural enemies through provision of nectar and alternative prey. We used an outside pot experiment to investigate the effect of three flower plants (Fagopyrum esculentum, Vicia faba, and Trifolium pratense) on reducing aphid pests on four different plant cultivars of barley (Hordeum vulgare), over two years. We grew the four cultivars of barley alone, next to a single flower or next to a mixture of flowers, and observed aphid and natural enemy colonization across the growing season. Aphid population sizes were reduced on all barley cultivars grown next to a flower with stronger pest suppression when all flowers were present. Each flower species recruited a different community of non-barley aphids that, in turn, varied in their ability to establish the natural enemy populations and subsequently the ability to reduce barley aphid populations. Overall, increased pest suppression in the mixed treatments was a result of numerous weaker interactions between different flower, aphid, and natural enemy species, rather than a few dominant interactions. Natural enemy communities could be enhanced by incorporating flower species that vary in their ability to attract and host alternative prey (i.e., non-pest aphids) as well as suitable nectar provisioning. We can use our knowledge of ecological interactions to tailor floral plantings to increase the effectiveness of pest control services.

17.
Plants (Basel) ; 9(10)2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33003550

RESUMEN

Roots typically grow downward into the soil where they anchor the plant and take up water and nutrients necessary for plant growth and development. While the primary roots usually grow vertically downward, laterals often follow a gravity set point angle that allows them to explore the surrounding environment. These responses can be modified by developmental and environmental cues. This review discusses the molecular mechanisms that govern root gravitropism in flowering plant roots. In this system, the primary site of gravity sensing within the root cap is physically separated from the site of curvature response at the elongation zone. Gravity sensing involves the sedimentation of starch-filled plastids (statoliths) within the columella cells of the root cap (the statocytes), which triggers a relocalization of plasma membrane-associated PIN auxin efflux facilitators to the lower side of the cell. This process is associated with the recruitment of RLD regulators of vesicular trafficking to the lower membrane by LAZY proteins. PIN relocalization leads to the formation of a lateral gradient of auxin across the root cap. Upon transmission to the elongation zone, this auxin gradient triggers a downward curvature. We review the molecular mechanisms that control this process in primary roots and discuss recent insights into the regulation of oblique growth in lateral roots and its impact on root-system architecture, soil exploration and plant adaptation to stressful environments.

18.
Plant Signal Behav ; 15(6): 1763005, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32408798

RESUMEN

Plant tissues naturally senesce over time. Attempts to improve plant robustness and increase longevity have involved genetic modification, application of synthetic chemicals, and use of beneficial microbes. Recently, culture supernatant from a microalga Chlorella fusca was found to prime innate immunity against Pseudomonas syringae in Arabidopsis thaliana. However, the capacity of Chlorella culture supernatants to prevent or delay aging in higher plants has not been elucidated. In this study, roots of the ornamental flowering plant Erinus alpinus L. were drenched with cell-free supernatants from three Chlorella species. Flower and leaf senescence in E. alpinus was significantly reduced and delayed with all three Chlorella supernatants. Investigations of the mode of action underlying delayed senescence showed that the Chlorella supernatants did not act as a chemical trigger to elicit plant immunity or as a growth-promoting fertilizer in E. alpinus. The mechanisms underlying the anti-aging effects remain undetermined, and several possible hypotheses are discussed. Several Chlorella species are industrially cultivated, and disposal of cell-free supernatant can be economically and environmentally challenging. This study provides a novel method for extending plant lifespan through use of Chlorella supernatant and discusses the potential of using industrial waste supernatants in agriculture and horticulture to reduce reliance on chemical pesticides and genetic modification.


Asunto(s)
Chlorella/metabolismo , Flores/metabolismo , Hojas de la Planta/metabolismo , Senescencia Celular/fisiología , Chlorella/fisiología , Flores/fisiología , Hojas de la Planta/fisiología
19.
Plant Cell Physiol ; 61(1): 88-104, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31513272

RESUMEN

Deschampsia antarctica is a Poaceae grass that has adapted to and colonized Antarctica. When D. antarctica plants were subjected to cold and dehydration stress both in the Antarctic field and in laboratory experiments, galactinol, a precursor of raffinose family oligosaccharides (RFOs) and raffinose were highly accumulated, which was accompanied by upregulation of galactinol synthase (GolS). The Poaceae monocots have a small family of GolS genes, which are divided into two distinct groups called types I and II. Type II GolSs are highly expanded in cold-adapted monocot plants. Transgenic rice plants, in which type II D. antarctica GolS2 (DaGolS2) and rice GolS2 (OsGolS2) were constitutively expressed, were markedly tolerant to cold and drought stress as compared to the wild-type rice plants. The RFO contents and GolS enzyme activities were higher in the DaGolS2- and OsGolS2-overexpressing progeny than in the wild-type plants under both normal and stress conditions. DaGolS2 and OsGolS2 overexpressors contained reduced levels of reactive oxygen species (ROS) relative to the wild-type plants after cold and drought treatments. Overall, these results suggest that Poaceae type II GolS2s play a conserved role in D. antarctica and rice in response to drought and cold stress by inducing the accumulation of RFO and decreasing ROS levels.


Asunto(s)
Galactosiltransferasas/genética , Oligosacáridos/análisis , Oryza/genética , Poaceae/genética , Rafinosa/análisis , Estrés Fisiológico/genética , Frío , Disacáridos/análisis , Sequías , Galactosiltransferasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Magnoliopsida/genética , Magnoliopsida/metabolismo , Malondialdehído/metabolismo , Oryza/metabolismo , Filogenia , Hojas de la Planta/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Poaceae/metabolismo , Semillas/química , Tiobarbitúricos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
20.
Int J Mol Sci ; 20(24)2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31817723

RESUMEN

Vegetative phase changes in plants describes the transition between juvenile and adult phases of vegetative growth before flowering. It is one of the most fundamental mechanisms for plants to sense developmental signals, presenting a complex process involving many still-unknown determinants. Several studies in annual and perennial plants have identified the conservative roles of miR156 and its targets, SBP/SPL genes, in guiding the switch of plant growth from juvenile to adult phases. Here, we review recent progress in understanding the regulation of miR156 expression and how miR156-SPLs mediated plant age affect other processes in Arabidopsis. Powerful high-throughput sequencing techniques have provided rich data to systematically study the regulatory mechanisms of miR156 regulation network. From this data, we draw an expanded miR156-regulated network that links plant developmental transition and other fundamental biological processes, gaining novel and broad insight into the molecular mechanisms of plant-age-related processes in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , MicroARNs/genética , Plantas Modificadas Genéticamente/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Desarrollo de la Planta/genética , Desarrollo de la Planta/fisiología , Plantas Modificadas Genéticamente/genética
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