Le pH des sols cultivés est en général compris entre 6 et 8,5. On trouve cependant des sols plus acides (podzols) dont le pH atteint des valeurs de l'ordre de 3, et des sols plus alcalins (sols salés) dont le pH peut être supérieur à 9.
Calvet
phanère
Production protectrice apparente de l'épiderme des vertébrés (poil, plume, ongle, griffe, dent).
Allain
phanérogame
Plante à fleurs (par opposition à cryptogame). SYN. : spermaphyte (« plante à graines »).
Le groupe des phanérogames réunit les plantes dont les organes reproducteurs sont regroupés dans une structure spécialisée appelée fleur, et qui produisent des graines. Il se divise en gymnospermes et angiospermes.
Henry
pharynx
Région anatomique située au fond de la cavité buccale, correspondant au croisement des voies respiratoires et digestives, constituée en particulier du voile du palais et de l'épiglotte.
Bougler/Gallouin
phelloderme
Tissu parenchymateux des tiges et des racines, produit vers l'intérieur par la face interne de l'assise génératrice.
Chaillou
phénologie
Étude de la chronologie des phénomènes biologiques saisonniers végétaux (feuillaison, floraison, etc.) et animaux (migration, hibernation, etc.), en relation avec le climat.
botanique.
Parmi les phénomènes périodiques, on note : pour les céréales, en tenant compte de la date de semis, les dates de levée, de tallage, de montaison, d'épiaison, de floraison et de moisson, et parfois les dates d'autres stades plus précis ; pour certaines plantes et pour les arbres, les dates de bourgeonnement, de feuillaison, de floraison, de maturité des fruits et de défeuillaison. Il existe pour certaines plantes des stades repères beaucoup plus nombreux, désignés par les lettres de l'alphabet accompagnées ou non d'indices chiffrés. L'utilisation des stades repères permet aux arboriculteurs et aux techniciens de s'entendre sur des termes précis, en particulier lors de la détermination des dates des traitements phytosanitaires.
zoologie.
Les observations phénologiques sur le règne animal comprennent par exemple l'époque d'arrivée, de départ ou de passage des oiseaux migrateurs, celle où les oiseaux sédentaires construisent leur nid ou font entendre leurs premiers chants, le moment où les animaux hibernent (chauves-souris, loirs), sortent de leur sommeil ou s'endorment, etc. D'une façon générale en France, à mesure qu'on avance vers le nord ou l'est, ou qu'on s'élève sur les massifs montagneux, ces phénomènes biologiques se trouvent retardés au printemps et avancés à l'automne.
Chaillou
phénotype
Manifestation externe ou apparente des caractères héréditaires contrôlés par les gènes.
Bougler/Gallouin
phéromone
1. Substance sécrétée par les glandes exocrines d'un animal, diffusée à l'extérieur et assurant une communication chimique entre les individus d'une même espèce. 2. Par extension, produit organique de synthèse qui présente les mêmes propriétés de médiateur chimique que cette substance.
Les phéromones sexuelles, les mieux connues, sont émises par les femelles ou par les mâles, et elles ont pour rôle de favoriser les rencontres entre les 2 sexes en vue de l'accouplement. Isolées chez les insectes, elles ont été identifiées, puis obtenues par synthèse. Les principales phéromones sexuelles de synthèse sont proposées aux agriculteurs par l'INRA sous forme de capsules attractives placées dans des pièges englués. Ces pièges sexuels attirent et capturent les insectes mâles, que l'agriculteur dénombre, ce qui lui permet de déterminer le moment le plus propice pour traiter sa culture avec le plus de chance d'efficacité. Il existe ainsi des phéromones pour attirer des carpocapses des pommes et des prunes, la tordeuse orientale du pêcher, les tordeuses de la pelure, des bourgeons, des céréales, de la grappe, de la pyrale du maïs, etc.
Chez l'animal, les phéromones permettent également la perception d'informations très diverses, telles que la présence du danger, l'identification des ennemis ou des amis, le rassemblement pour le combat ou la migration, la présence de nourriture, la nécessité de se reproduire, etc.
Bougler/Gallouin
philodendron
Plante originaire d'Amérique du Sud, cultivée comme plante d'appartement (genres Philodendron et Monstera, famille des aracées).
Il existe de nombreuses espèces de philodendrons : Philodendron scandens, qui résiste aux basses températures, Philodendron erubescens, Monstera deliciosa, couramment vendu sous le nom de philodendron, et Philodendron selloum (ou Philodendron bipinnatifidum).
Culture.
Les philodendrons demandent une température voisine de 18 °C. Ils craignent le soleil direct et sont souvent peu exigeants sur la quantité de lumière. Ils ont besoin d'une humidité de l'air élevée. Leur culture se fait dans un mélange aéré et bien drainé (terre de bruyère, tourbe ou terreau de feuilles avec sable et polystyrène expansé). Les plantes grimpantes ont besoin d'un tuteur, qui, lorsqu'il est enrobé de mousses, peut permettre la fixation des racines aériennes. Celles-ci ne doivent pas être supprimées, mais mises en terre. La multiplication des philodendrons s'effectue par bouturage de tronçons ou d'extrémités de tige munis d'une feuille, par marcottage aérien ou par semis. La température du sol doit être de 20 à 25 °C pour obtenir l'enracinement ou la levée en 15 à 30 jours. Les philodendrons peuvent être attaqués par les cochenilles et les araignées rouges.
Dorion
phlox
Plante annuelle ou vivace originaire d'Amérique du Nord, cultivée pour son abondante floraison, printanière ou estivale (genre Phlox, famille des polémoniacées).
Les phlox sont cultivés pour les jardins et pour la production de fleurs coupées. Les espèces annuelles comprennent en particulier le phlox de Drummond (Phlox drummondii), le plus cultivé. Les espèces vivaces rassemblent les hybrides P. ´ horurum (croisements de Phlox paniculata et Phlox maculata) et les espèces naines, telles que amaena et Phlox subulata.
La multiplication des phlox annuels s'effectue par semis en place ou bouturage. Celle des phlox vivaces se fait en mai-juin par bouturage de racines afin d'éviter la propagation des nématodes des tiges, qui sont les principaux ravageurs. La plantation a lieu entre octobre et avril dans une terre de bonne qualité, fraîche, bien drainée, à exposition ensoleillée.
Dorion
>
We Care About Your Privacy
We and our 909 partners store and access personal data, like browsing data or unique identifiers, on your device. Selecting "I Accept" enables tracking technologies to support the purposes shown under "we and our partners process data to provide," whereas selecting "Reject All" or withdrawing your consent will disable them. If trackers are disabled, some content and ads you see may not be as relevant to you. You can resurface this menu to change your choices or withdraw consent at any time by clicking the ["privacy preferences"] link on the bottom of the webpage [or the floating icon on the bottom-left of the webpage, if applicable]. Your choices will have effect within our Website. For more details, refer to our Privacy Policy.
We and our partners process data to provide:
Use precise geolocation data. Actively scan device characteristics for identification. Store and/or access information on a device. Personalised advertising and content, advertising and content measurement, audience research and services development.
About Your Privacy
Your Privacy
Targeting Cookies
Functional Cookies
Performance Cookies
Strictly Necessary Cookies
Store and/or access information on a device 736 partners can use this purpose
Personalised advertising and content, advertising and content measurement, audience research and services development 875 partners can use this purpose
Use precise geolocation data 280 partners can use this special feature
Actively scan device characteristics for identification 148 partners can use this special feature
Ensure security, prevent and detect fraud, and fix errors 562 partners can use this special purpose
Deliver and present advertising and content 564 partners can use this special purpose
Match and combine data from other data sources 404 partners can use this feature
Link different devices 349 partners can use this feature
Identify devices based on information transmitted automatically 535 partners can use this feature
Save and communicate privacy choices 405 partners can use this special purpose
Your Privacy
We process your data to deliver content or advertisements and measure the delivery of such content or advertisements to extract insights about our website. We share this information with our partners on the basis of consent. You may exercise your right to consent, based on a specific purpose below or at a partner level in the link under each purpose. Some vendors may process your data based on their legitimate interests, which does not require your consent. You cannot object to tracking technologies placed to ensure security, prevent fraud, fix errors, or deliver and present advertising and content, and precise geolocation data and active scanning of device characteristics for identification may be used to support this purpose. This exception does not apply to targeted advertising. These choices will be signaled to our vendors participating in the Transparency and Consent Framework.
More information
Targeting Cookies
These cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising.
Functional Cookies
These cookies enable the website to provide enhanced functionality and personalisation. They may be set by us or by third party providers whose services we have added to our pages. If you do not allow these cookies then some or all of these services may not function properly.
Performance Cookies
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Strictly Necessary Cookies
Always Active
These cookies are necessary for the website to function and cannot be switched off in our systems. They are usually only set in response to actions made by you which amount to a request for services, such as setting your privacy preferences, logging in or filling in forms. You can set your browser to block or alert you about these cookies, but some parts of the site will not then work. These cookies do not store any personally identifiable information.
Store and/or access information on a device 736 partners can use this purpose
Cookies, device or similar online identifiers (e.g. login-based identifiers, randomly assigned identifiers, network based identifiers) together with other information (e.g. browser type and information, language, screen size, supported technologies etc.) can be stored or read on your device to recognise it each time it connects to an app or to a website, for one or several of the purposes presented here.
Personalised advertising and content, advertising and content measurement, audience research and services development 875 partners can use this purpose
Use limited data to select advertising 698 partners can use this purpose
Advertising presented to you on this service can be based on limited data, such as the website or app you are using, your non-precise location, your device type or which content you are (or have been) interacting with (for example, to limit the number of times an ad is presented to you).
Create profiles for personalised advertising 554 partners can use this purpose
Information about your activity on this service (such as forms you submit, content you look at) can be stored and combined with other information about you (for example, information from your previous activity on this service and other websites or apps) or similar users. This is then used to build or improve a profile about you (that might include possible interests and personal aspects). Your profile can be used (also later) to present advertising that appears more relevant based on your possible interests by this and other entities.
Use profiles to select personalised advertising 554 partners can use this purpose
Advertising presented to you on this service can be based on your advertising profiles, which can reflect your activity on this service or other websites or apps (like the forms you submit, content you look at), possible interests and personal aspects.
Create profiles to personalise content 245 partners can use this purpose
Information about your activity on this service (for instance, forms you submit, non-advertising content you look at) can be stored and combined with other information about you (such as your previous activity on this service or other websites or apps) or similar users. This is then used to build or improve a profile about you (which might for example include possible interests and personal aspects). Your profile can be used (also later) to present content that appears more relevant based on your possible interests, such as by adapting the order in which content is shown to you, so that it is even easier for you to find content that matches your interests.
Use profiles to select personalised content 219 partners can use this purpose
Content presented to you on this service can be based on your content personalisation profiles, which can reflect your activity on this or other services (for instance, the forms you submit, content you look at), possible interests and personal aspects. This can for example be used to adapt the order in which content is shown to you, so that it is even easier for you to find (non-advertising) content that matches your interests.
Measure advertising performance 799 partners can use this purpose
Information regarding which advertising is presented to you and how you interact with it can be used to determine how well an advert has worked for you or other users and whether the goals of the advertising were reached. For instance, whether you saw an ad, whether you clicked on it, whether it led you to buy a product or visit a website, etc. This is very helpful to understand the relevance of advertising campaigns.
Measure content performance 389 partners can use this purpose
Information regarding which content is presented to you and how you interact with it can be used to determine whether the (non-advertising) content e.g. reached its intended audience and matched your interests. For instance, whether you read an article, watch a video, listen to a podcast or look at a product description, how long you spent on this service and the web pages you visit etc. This is very helpful to understand the relevance of (non-advertising) content that is shown to you.
Understand audiences through statistics or combinations of data from different sources 507 partners can use this purpose
Reports can be generated based on the combination of data sets (like user profiles, statistics, market research, analytics data) regarding your interactions and those of other users with advertising or (non-advertising) content to identify common characteristics (for instance, to determine which target audiences are more receptive to an ad campaign or to certain contents).
Develop and improve services 596 partners can use this purpose
Information about your activity on this service, such as your interaction with ads or content, can be very helpful to improve products and services and to build new products and services based on user interactions, the type of audience, etc. This specific purpose does not include the development or improvement of user profiles and identifiers.
Use limited data to select content 159 partners can use this purpose
Content presented to you on this service can be based on limited data, such as the website or app you are using, your non-precise location, your device type, or which content you are (or have been) interacting with (for example, to limit the number of times a video or an article is presented to you).
Use precise geolocation data 280 partners can use this special feature
With your acceptance, your precise location (within a radius of less than 500 metres) may be used in support of the purposes explained in this notice.
Actively scan device characteristics for identification 148 partners can use this special feature
With your acceptance, certain characteristics specific to your device might be requested and used to distinguish it from other devices (such as the installed fonts or plugins, the resolution of your screen) in support of the purposes explained in this notice.
Ensure security, prevent and detect fraud, and fix errors 562 partners can use this special purpose
Always Active
Your data can be used to monitor for and prevent unusual and possibly fraudulent activity (for example, regarding advertising, ad clicks by bots), and ensure systems and processes work properly and securely. It can also be used to correct any problems you, the publisher or the advertiser may encounter in the delivery of content and ads and in your interaction with them.
Deliver and present advertising and content 564 partners can use this special purpose
Always Active
Certain information (like an IP address or device capabilities) is used to ensure the technical compatibility of the content or advertising, and to facilitate the transmission of the content or ad to your device.
Match and combine data from other data sources 404 partners can use this feature
Always Active
Information about your activity on this service may be matched and combined with other information relating to you and originating from various sources (for instance your activity on a separate online service, your use of a loyalty card in-store, or your answers to a survey), in support of the purposes explained in this notice.
Link different devices 349 partners can use this feature
Always Active
In support of the purposes explained in this notice, your device might be considered as likely linked to other devices that belong to you or your household (for instance because you are logged in to the same service on both your phone and your computer, or because you may use the same Internet connection on both devices).
Identify devices based on information transmitted automatically 535 partners can use this feature
Always Active
Your device might be distinguished from other devices based on information it automatically sends when accessing the Internet (for instance, the IP address of your Internet connection or the type of browser you are using) in support of the purposes exposed in this notice.
Save and communicate privacy choices 405 partners can use this special purpose
Always Active
The choices you make regarding the purposes and entities listed in this notice are saved and made available to those entities in the form of digital signals (such as a string of characters). This is necessary in order to enable both this service and those entities to respect such choices.