#viola arvensis

[plantsinposts]

Hi again! I saw some violets(?) growing out of a wall.

I'm pretty sure they're violets, but I don't know the specific species.

I did need a little seek app help on this one, but it looks like it's a field pansy: Viola arvensis. So yes, another violet! From none other than violetnshenanigans of course. It's native to a pretty wide area of Eurasia, and naturalized in the US, but restricted to mostly urban environments there it seems like. Wall crack seems like a good spot for it!

[carolinawrenn]

European field pansy (Viola arvensis)

[taimemaailm]

Põldkannike (Viola arvensis)

Saksa keeles Acker-Stiefmütterchen, inglise keeles field pansy. Eesti keeles ka tuntud annasilma, vaeselapsesilmavesi või põlluvõõrasema nime all.

Üheaastaline õistaim kannikese perekonnast, kannikeseliste sugukonnas, mis on malpiigialaadsete seltsi osa.

Ta on pärit Euroopast, Lääne-Aasiast ja Põhja-Aafrikast, aga esineb ka teistel mandritel. Kasvab enamasti jäätmaadel ja põldudel, aga ka karjamaadel ja aedades, eriti liivakatel ja kuivematel muldadel.

Ühest taimest võivad tulla üle 2500 seemne, mis võivad 5 aastat mullas idanemisvõime säilitada ja tärkata ka veel 5 cm sügavuses. Idaneb kiiremini pärast talvitamist. Kasvab 10-40 cm kõrguseni. Õitseb kevadel ja suvel.

Taime on uuritud potentsiaalse vähirohi toorainena. Samuti sisaldab toimeaineid mis aitavad peavalu ja nahahaiguste vastu. Tehakse ka ravimteed mis kasutakse külmetuse ajal.

Pilt: Didier Descouens, CC BY SA 4.0, Wikimedia Commons

[entomoblog]

Les fleurs laissent tomber les insectes pollinisateurs

See on Scoop.it - Insect Archive

"Tandis que les insectes déclinent, les fleurs évoluent rapidement pour devenir moins attractives et dépendantes des pollinisateurs. Un cercle vicieux, les insectes ayant besoin du nectar des fleurs."

Avec moins d’insectes pour les polliniser, les fleurs s’en détournent pour trouver d’autres stratégies de reproduction. Mais les pollinisateurs ont aussi besoin des fleurs. Samson Acoca-Pidolle, Fourni par l'auteur

  Publié: 12 mai 2024, 11:50 EDT

Samson Acoca-Pidolle

Doctorant en écologie évolutive, Université de Montpellier

  "Alors que le déclin des insectes ne ralentit pas, de nouvelles questions se posent quant à la manière dont les plantes, qui ont besoin des pollinisateurs, s’adaptent. Comment font-elles pour se reproduire dans ces conditions ? Dans une récente étude que nous avons menée, nous comparons des fleurs de pensée des champs (Viola arvensis) poussant aujourd’hui dans la région parisienne à des plantes plus anciennes de la même espèce, « ressuscitées » à partir de graines collectées il y a 20 à 30 ans. Nous avons trouvé que les fleurs actuelles sont 10 % plus petites, produisent 20 % moins de nectar que leurs ancêtres, des caractéristiques importantes pour attirer les pollinisateurs, qui viennent en conséquence moins les visiter. Ces changements montrent que les liens qui nouent les pensées à leurs pollinisateurs sont en train de se rompre.

  Pour mettre en évidence l’évolution des fleurs actuelles par rapport à leurs ancêtres, nous avons eu recours à une méthode appelée « écologie de la résurrection ». Cette pratique consiste à comparer des individus issus d’une même espèce, mais récoltés à plusieurs années d’intervalle.

  Dans le cas de cette étude, publiée dans le journal scientifique New Phytologist, les plantes anciennes ont été « ressuscitées » depuis des graines collectées dans les années 1990-2000 et conservées par les Conservatoires botaniques nationaux de Bailleul et du Bassin parisien. Ces plantes anciennes ont été comparées à des plantes prélevées en 2021. La comparaison entre les pensées anciennes et leurs descendantes poussant de nos jours dans les mêmes champs du Bassin parisien permet de comprendre l’évolution de l’espèce au cours de ces 20 à 30 dernières années.

Le déclin des pollinisateurs, responsable désigné ?

C’est ainsi que nous avons pu étudier l’évolution de quatre populations de pensées des champs, une plante messicole, c’est-à-dire une plante sauvage présente dans les cultures agricoles, dans le Bassin parisien. Les plantes messicoles jouent un rôle important dans les services de pollinisation en attirant les insectes pollinisateurs et en leur offrant une ressource diversifiée. Le déclin de l’attractivité des messicoles pourrait diminuer l’attraction des pollinisateurs, pourtant nécessaires aux bons rendements de 75 % des cultures agricoles.

  La moindre attractivité des fleurs pour les pollinisateurs est vraisemblablement leur réponse au déclin des insectes durant les dernières décennies, rapporté par plusieurs études à travers l’Europe. Plus de 75 % de la biomasse d’insectes volants, dont font partie les pollinisateurs, a disparu dans les aires protégées allemandes en 30 ans. Les pensées des champs, comme la majorité des plantes à fleurs, sont le fruit d’une coévolution avec leurs pollinisateurs durant des millions d’années pour arriver à une relation à bénéfice réciproque. La plante produit du nectar pour les insectes, et les insectes en contrepartie assurent le transport du pollen entre fleurs, assurant leur reproduction.

  Avec le déclin des pollinisateurs, et donc du transfert de pollen entre fleurs, la reproduction des plantes devient plus difficile. Les résultats de cette étude révèlent que les pensées sont donc en train d’évoluer afin de se passer des pollinisateurs pour leur reproduction. Elles pratiquent de plus en plus l’autofécondation, qui consiste à se reproduire avec soi-même, ce qui est possible pour les plantes hermaphrodites, soit 90 % des plantes à fleurs environ.

  Une évolution similaire a déjà été observée lors d’expériences où des plantes, en seulement quelques générations et en l’absence de pollinisateurs se reproduisent plus par autofécondation et produisent des fleurs avec moins de nectar et moins attractives que leurs congénères pollinisées par des insectes. Notre étude est en revanche la première à montrer que le déclin des pollinisateurs pourrait déjà être responsable d’une évolution vers l’autofécondation dans la nature.

Des conséquences pour l’ensemble de l’écosystème

L’autofécondation est une stratégie reproductive qui peut être efficace sur le court terme mais qui limiterait la capacité de l’espèce à s’adapter aux changements environnementaux futurs en réduisant la diversité génétique, ce qui augmenterait donc les risques d’extinction.

  Ces résultats sont également une mauvaise nouvelle pour les pollinisateurs et le reste de la chaîne alimentaire. Notre étude a en effet mis en évidence un cercle vicieux : une réduction de la production de nectar par les plantes signifie moins de nourriture pour les insectes, ce qui peut à son tour contribuer à menacer les populations de pollinisateurs. Nous montrons que le déclin des pollinisateurs n’a pas que des conséquences démographiques mais également évolutives qui sont d’autant plus difficiles à inverser."

  Ongoing convergent evolution of a selfing syndrome threatens plant–pollinator interactions 

  Vous aimerez aussi

Les animaux et les plantes peuvent-ils s’entraider ?

Pourquoi toutes les fleurs ne sentent pas la rose… loin de là !

Guerre et paix chez les insectes floricoles

Quand l’alimentation des abeilles sauvages raconte les modifications de leur environnement

[currenthunt]

Scientists uncover evidence of rapid evolution in a flowering plant found in Paris, France

Recently, scientists have uncovered evidence of rapid evolution in a flowering plant found in Paris, France. The plant, identified as Field Pansy (Viola arvensis) is showing signs of self-pollination, a behaviour contradicting the conventional reliance on external pollinators. Key Facts about Field Pansy - The Field Pansy (Viola arvensis), is a common wildflower that can be found in many parts of Europe, Asia, and North America. - It belongs to the group of plants called angiosperms, which produce seeds inside a protective structure called a fruit. - Angiosperms rely on insects and other animals to pollinate them and help them reproduce. Pollination - Pollination is the process by which pollen grains, which contain the male reproductive cells of plants, are transferred from one flower to another, usually by insects that visit the flowers for nectar. - Nectar is a sugary liquid that plants produce to attract pollinators. - Pollination is essential for the genetic diversity and survival of many plant species, and it has evolved over 100 million years of coevolution between plants and animals. - Pollination is carried through pollinators(vectors that move pollen within the flower and from flower to flower). - However, some plants can also pollinate themselves, without the help of any external agent. This is called self-pollination, and it is a way for plants to ensure their reproduction in case there are no suitable pollinators around. - Self-pollination can also save energy and resources for plants, as they do not need to produce as much nectar and flowers to attract pollinators. Highlights of the Study Rapid Evolution - The study marks the first evidence of rapid evolution in plants, with the field pansy, showing significant changes in nectar production and flower size over a relatively short period. - The study found that flowers of the wild pansy variety produced 20% less nectar and were 10% smaller. Self-Pollination - The field pansy has evolved to self-pollinate, reducing its reliance on pollinators due to a decreasing availability of insects. - This behaviour is contrary to the conventional reliance on insects for pollination in angiosperms, marking a significant departure from established plant reproductive strategies. Convergent Evolution - The study reveals convergent evolution across populations, with a reduction in rewarding traits and attractiveness to pollinators. - This convergence suggests a consistent evolutionary response to environmental pressures across different plant populations. Resurrection Ecology Method - The researchers used the "resurrection ecology" method, planting seeds from the 1990s and 2000s against their contemporary descendants from 2021 to observe changes over time. - This method allowed them to track and compare changes in plant traits and behaviour across different periods. Environmental Impact - The move towards selfing may benefit plants in the short term but poses a threat to their long-term survival, especially in the face of climate change and other environmental changes. - Self-pollination reduces the genetic diversity and adaptability of the plant, making it more susceptible to diseases and environmental stresses. Pollinator Decline - The study warns of a potential feedback loop that could lead to further declines in pollinators as a result of plant trait evolution, impacting the plant-pollinator network. Urgent Analysis - The study emphasizes the need to analyze whether these results are symptomatic of broader behavioral changes in the relationship between angiosperms and their pollinators. - Researchers call for a thorough understanding of the possibility of reversing the process and breaking the eco-evolutionary-positive feedback loop to preserve plant-pollinator networks. Read the full article

[xtruss]

The Age of Extinction: Flowers ‘Giving Up’ On Scarce Insects And Evolving To Self-Pollinate, Say Scientists

French wild pansies are producing smaller flowers and less nectar than 20 to 30 years ago in ‘startling’ act of evolution, study shows

— Phoebe Weston | Tuesday 19 December 2023 | The Guardian USA

Field pansies (Viola Arvensis) growing near Paris produced 20% less nectar than those growing there 20 to 30 years ago, the study found. Photograph: Courtesy of Samson Acoca-Pidolle

Flowers are “giving up on” pollinators and evolving to be less attractive to them as insect numbers decline, researchers have said.

A study has found the flowers of field pansies growing near Paris are 10% smaller and produce 20% less nectar than flowers growing in the same fields 20 to 30 years ago. They are also less frequently visited by insects.

“Our study shows that pansies are evolving to give up on their pollinators,” said Pierre-Olivier Cheptou, one of the study’s authors and a researcher at the French National Centre for Scientific Research. “They are evolving towards self-pollination, where each plant reproduces with itself, which works in the short term but may well limit their capacity to adapt to future environmental changes.”

Plants produce nectar for insects, and in return insects transport pollen between plants. This mutually beneficial relationship has formed over millions of years of coevolution. But pansies and pollinators may now be stuck in a vicious cycle: plants are producing less nectar and this means there will be less food available to insects, which will in turn accelerate declines.

“Our results show that the ancient interactions linking pansies to their pollinators are disappearing fast,” said lead author Samson Acoca-Pidolle, a doctoral researcher at the University of Montpellier. “We were surprised to find that these plants are evolving so quickly.”

Insect declines have been reported by studies across Europe. One study on German nature reserves found that from 1989 to 2016 the overall weight of insects caught in traps fell by 75%. Acoca-Pidolle added: “Our results show that the effects of pollinator declines are not easily reversible, because plants have already started to change. Conservation measures are therefore urgently needed to halt and reverse pollinator declines.”

The method used in the study is called “resurrection ecology”. It involved germinating ancestral pansy plants from seeds collected in the 1990s and 2000s, which were being stored in the national botanical conservatories. The team compared how four populations of field pansies (Viola arvensis) had changed during this period.

Other than changes to the flowers, they found no other changes between the populations, such as the leaf size or total size of the plant, according to the paper, published in the journal New Phytologist.

If flowers are not likely to attract insects, then a plant is wasting energy making them large and nectar-rich. Previous research has shown the percentage of field pansies relying on self-pollination has increased by 25% over the past 20 years.

Support the GuardianRelated articleHuman-driven extincition of bird species twice as high as thought, study saysRead more

“This is a particularly exciting finding as it shows evolution happening in real time,” said Dr Philip Donkersley, from Lancaster University, who was not involved in the study.

“The fact that these flowers are changing their strategy in response to decreasing pollinator abundance is quite startling. This research shows a plant undoing thousands of years of evolution in response to a phenomenon that has been around for only 50 years.

“Although most research has been done in Europe and North America, we know that pollinator declines are a global phenomenon. These results may just be the tip of the iceberg: areas with far greater plant diversity will likely have many more examples of wild plants changing their pollination strategies in response to a lack of pollinators.”

Foxgloves have evolved to enable pollination by Hummingbirds in Costa Rica, rather than bees, after being introduced to the country 200 years ago. Photograph: Christopher Bellette/Alamy

Similar processes can be seen in invasive populations that need to adapt new ecological niches. Populations of foxglove have evolved to be pollinated by bumblebees in Europe. However, 200 years ago they were introduced to Costa Rica and Colombia, and they have since changed the shape of their flowers so they can be pollinated by hummingbirds, researchers found.

Other research shows plants that are unable to self-pollinate go the other way, producing more pollen when pollinators are scarce. Because they cannot resort to other methods, they have to outcompete other plants to attract a shrinking number of pollinators.

Prof Phil Stevenson, from Royal Botanic Gardens, Kew, who was also not involved in the research, said it made sense that traits that guide or reward pollinators are likely to change when the number of pollinators drops, especially among species that have the option of self-pollinating.

“This is especially so for reproduction,” he said, “which is arguably the most important living function of organisms and likely the most adaptive trait of all.”

[erbariofitoterapicoalimurgico]

Brassica rapa subsp. sylvestris "Caluzzo" in Siciliano (Nata spontanea in un vaso, Villafrati) È parente di molte piante utilizzate in tutto il mondo: ravizzone (in primis), senape, navone, rapa, cavolo cinese, colza... È una brassicacea EDULE dalle foglie pubescenti (ruvide) di cui si raccolgono le foglie tenere prima che si formi il fusto e i fiori gialli. È simile a molte varietà dalle quali si può distinguere, non con facilità, per alcuni particolari: brassica fruticulosa (che ha foglie glabre, verde-glauche ed è più tipica della Sicilia Orientale), brassica nigra (foglie verde scuro e fusto violaceo), brassica rupestris subsp. rupestris (foglie glabre progressivamente più piccole verso l'alto, fusto legnoso alla base), sinapis pubescens subsp. pubescens (foglie basali con almeno 5 segmenti laterali), sinapis arvensis (fusto violaceo, foglie basali con segmenti lungo tutto il picciolo), Hirschfeldia incana (basali lobate a contorno molto più spatolato, cauline piccolissime o quasi nulle), sinapis alba (foglie sempre picciolate, con 7-9 segmenti, profondamente dentate), raphanus raphanistrum (foglie picciolate tutte completamente segmentate, fiore bianco venato di viola, giallino al centro). Tutte queste piante si possono trovare selvatiche nel nostro territorio (almeno in quello siciliano) e sono comunque eduli, quindi anche confonderle tra loro non dovrebbe causare grossi problemi. Molto spesso si ibridano fra loro. La ricerca verge molto infatti sulla classificazione genetica. Accumula cadmio, zinco (e potenzialmente anche altri metalli pesanti), è quindi importante raccoglierla in natura, lontana da possibili contaminazioni. I semi oleosi, essendo il ravizzone il parente più prossimo (se non proprio la stessa pianta) dovrebbero essere ricchi di omega 3. L'olio che se ne ricava è emolliente e lassativo, ma con dell'acido erucico (tossico in dosi eccessive). È una verdura non troppo adatta a chi soffre di gotta e iperuricemia, o ne è predisposto. Non si trovano i suoi valori nutrizionali specifici, si suppongono comunque molto similari a quelli delle cime di rapa, utili in diete ipocaloriche e ricche di calcio, potassio, fosforo, Vit. C e K. https://www.instagram.com/p/Cjx4QGnNYMa/?igshid=NGJjMDIxMWI=

[frank-olivier]

Sunday, May 23, 2021

[awkwardbotany]

Ground Beetles as Weed Seed Predators

Ground Beetles as Weed Seed Predators

As diurnal animals, we are generally unaware of the slew of animal activity that occurs during the night. Even if we were to venture out in the dark, we still wouldn’t be able to detect much. Our eyes don’t see well in the dark, and shining a bright light to see what’s going on results in chasing away those creatures that prefer darkness. We just have to trust that their out there, and in the…

[los-plantalones]

flowers of the field.

[stefano-bonalume]

Viola arvensis

[dumb-bird]

Found two different violets today on the way to the store! They both were so tiny.

Can't explore much nowadays but still, it's flower season!

Tumblr shows images once in 2-3 days, so I'm rarely on but I'll try to still be here.

[naturalxnotizblog]

Acker-Stiefmütterchen, Viola arvensis: https://naturalxnotizblog.wordpress.com/tag/malpighiales/

[solbacka]

May Day May Day !

Today the sun is dancing after the late snow of the last few days. The temperature seems to be on the rise, finally. April was very cool and nothing much seemed to be happening in the garden very fast. But now, the forecasts look promising, and the garden is kicking into gear. I’m already there, revved up and running.

As you might have noticed, I haven’t been able to give Tumblr that much time. Since the few calmer weeks after the last school project ended in March, I have been given the first design assignment at work. My proposal for a bit of land art was approved. I’m very excited about it! The timetable is crazy — the plans should be ready and executable after a fortnight or so! And then I should be guiding the process of making it happen. Phew! This year seems to be turning into one of the busiest of my life. So, I won’t be able to check in here as often as I would like but I’ll try to keep posting pictures if nothing else.

Thank you to everyone following this mad dash! I so appreciate all the loyal friends and followers. I hope that the new followers will feel welcome at this quiet corner of the site. Each of you is important in your own way!

Thank you for all the reblogs, dear curators and rebloggers! You are all doing a great job in keeping the ball rolling whether you share, promote or hoard, or all of the above. :D And thank you everyone for the likes! I appreciate each and everyone of them!

Now let us all dance around the maypole and sing: “In the woods there grew a tree and a fine, fine tree was he...”

Lots of 💕,

                 Daniel

[alittleperplexed]

Viola arvensis

[luc3]

Picking, or sometimes just touching a plant, could often lead to unfortunate consequences.

In Valence, the young girl who handles wild mustard (Sinapis arvensis) will fight with her mother-in-law; in Vienna, she must never touch a white violet (Viola odorata) before getting married; in Belgium, collecting poppies brings storms (Papaver Rhoeas).

(...) Other prohibitions are based on the belief that dangerous animals are lurking near the plant or that the plant itself is some kind of poison.

In Vienna, the peasants consider the watercress (Cardamine pratensis) as the favorite flower of snakes, to collect it means to be stung during the year.

In Provence, if after a curse prayer, a very dry marsh bean (Vicia faba) is thrown into the oil of a lamp that burns near an altar, as soon as it begins to swell, the one who is cursed falls ill and the day she separates, he dies without any remedy being able to save him.

In Liege, to make an inconstant lover suffer, we put an onion pierced with thirteen pins in the fireplace while we light a candle also pierced with thirteen pins.

In Vienna again, a niello flower (Agrostemma Githago) offered to a young girl by an old woman causes her to die or go mad if the stem is cut or broken in the middle.

In Brittany formerly, digitalis flowers (Foxgloves) were hung on each of the stingers of a thorn cross, to be then worn by the person to whom one wanted to harm ; the latter would die shortly after having kissed or touched the cross.

--

(in P. Sebillot, le Folfklore de France, la flore.)