L'Orobanche minor, quella strana pianta parassita che sbuca dal prato

Mario Pria
/
14 giugno 2018
/
Views 894

Ha la necessità di riprodursi; ed ecco, dunque, che produce fiori, anche carini, ermafroditi, ad impollinazione entomofila

Ma che cos'è questa strana pianta che spunta dal prato?
Ebbene cari amici, si tratta di una pianta parassita...proprio così! Vale la pena parlarne, poichè è interessante. Ecco a voi l'Orobanche minor! Il nome di origine greca deriva da "òrobos" (legume), e "anchèin" (strozzare).
Come mai?
Perchè parassitizza le leguminose (nel mio caso un prato di trifoglio). Le sue radici, infatti, sono dotate di particolari organi, detti "austori" (termine prestato dalla micologia), che, a somiglianza delle "ife" fungine, penetrano nelle radici delle piante parassitizzate per ricavarne le sostanze nutritive con cui sopravvivono.
Ma come mai le leguminose?
Perchè le piante di questa famiglia posseggono una capacità unica, nel mondo vegetale: quelle di "fissare" l'azoto atmosferico, attraverso l'azione di alcuni batteri "simbionti", come il Rhizobium, che effettuano la "nitrogenasi", una reazione chimica che trasforma l'azoto molecolare atmosferico (N2), in azoto ammonico (NH3). In questa forma l'azoto (che ricordiamo essere il componente più presente nell'atmosfera terrestre, il 78% del volume totale) riesce ad essere solubilizzato e sciolto nella soluzione circolante del terreno, e quindi facilmente assorbito.
Ma è anche interessante notare come l'Orobanche abbia delle foglie non fotosintetizzanti, che non contengono clorofilla, dunque di colore bruno. Come mai? Perchè assume gli elaborati già fatti, non ha dunque la necessità di sintetizzare gli zuccheri! La necessità che ha, invece, è quella di riprodursi; ed ecco, dunque, che produce fiori, anche carini, ermafroditi, ad impollinazione entomofila (cioè tramite gli insetti). I semi che ne derivano, cadendo a terra, vengono spesso dispersi dalle formiche (disseminazione "mirmecoria"), e per germinare, pensate, hanno bisogno delle radici delle piante ospiti!

Nonostante sia una pianta parassita, quindi, cioè che vive a spese di altre piante, ha un ciclo molto ineressante. Come tutti i parassiti tende a non uccidere l'organismo che lo ospita, che quindi sopravvive tranquillamente alla ingombrante presenza dell'esoso ospite. Magari si potesse dire così anche degli omologhi parassiti umani...

Mario Pria

Dr.agr. Mario Emanuele Pria - Manutenzione giardini e terrazzi - Corsi online di giardinaggio - www.marioemmepi.it - marioemmepi@gmail.com - 3356032955

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Tags: infestante leguminose parassita pianta

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Category passione-natura not found
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FTL stack trace ("~" means nesting-related):
- Failed at: @get_category name=cat_name var="cate... [in template "dev.sevendaysweb.com/layouts/macro/utils.ftl" in macro "set_primary_category_color" at line 600, column 7]
- Reached through: @set_primary_category_color c [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "hs_contents" at line 970, column 25]
- Reached through: @hs_contents ca, contents_preview, co... [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "suggested_category_content" at line 461, column 17]
- Reached through: @suggested_category_content ca, last_... [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "suggested_contents" at line 223, column 25]
- Reached through: @query name=name cache=false start=st... [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "suggested_contents" at line 221, column 9]
- Reached through: @suggested_contents name=(mpName + "i... [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "content_suggested" at line 81, column 41]
- Reached through: @query name="categories_area_sect" ca... [in template "dev.sevendaysweb.com/layouts/macro/content_suggested.ftl" in macro "content_suggested" at line 8, column 9]
- Reached through: @content_suggested bundle.OCDetail, "... [in template "dev.sevendaysweb.com/layouts/macro/content_details.ftl" in macro "content_details" at line 357, column 25]
- Reached through: @content var="c" show_last_content=ca... [in template "dev.sevendaysweb.com/layouts/macro/content_details.ftl" in macro "content_details" at line 118, column 9]
- Reached through: @content_details img_full_width=img_f... [in template "dev.sevendaysweb.com/layouts/default.ftl" in macro "contents_column" at line 9, column 13]
- Reached through: @contents_column [in template "dev.sevendaysweb.com/layouts/macro/skeleton.ftl" in macro "container" at line 412, column 49]
- Reached through: @query name="count_areas" cache=false... [in template "dev.sevendaysweb.com/layouts/macro/skeleton.ftl" in macro "container" at line 254, column 5]
- Reached through: @container context, "[left-mid-", "[c... [in template "dev.sevendaysweb.com/layouts/macro/skeleton.ftl" in macro "html" at line 111, column 33]
- Reached through: @cache sv=search_val [in template "dev.sevendaysweb.com/layouts/macro/skeleton.ftl" in macro "html" at line 66, column 9]
- Reached through: @html cat_layout="home" cat_title=tru... [in template "dev.sevendaysweb.com/layouts/default.ftl" at line 24, column 1]
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Java stack trace (for programmers):
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freemarker.template.TemplateException: [... Exception message was already printed; see it above ...]
at it.treis.utils.freemarker.BasicHeadingCategoryDirective.getCategoryByName(BasicHeadingCategoryDirective.java:63)
at it.treis.utils.freemarker.CategoryDirective.execute(CategoryDirective.java:65)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:148)
at freemarker.core.Environment.visitIteratorBlock(Environment.java:559)
at freemarker.core.IteratorBlock.accept(IteratorBlock.java:67)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:2255)
at it.treis.utils.freemarker.CategoryCachedQueryResultDirective.execute(CategoryCachedQueryResultDirective.java:202)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:148)
at freemarker.core.Environment.visitIteratorBlock(Environment.java:559)
at freemarker.core.IteratorBlock.accept(IteratorBlock.java:67)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:2255)
at it.treis.utils.freemarker.CategoryCachedQueryResultDirective.execute(CategoryCachedQueryResultDirective.java:202)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:2255)
at it.treis.utils.freemarker.ContentCachedResultDirective.render(ContentCachedResultDirective.java:201)
at it.treis.utils.freemarker.ContentCachedResultDirective.execute(ContentCachedResultDirective.java:181)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.IfBlock.accept(IfBlock.java:48)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:2255)
at it.treis.utils.freemarker.CategoryCachedQueryResultDirective.execute(CategoryCachedQueryResultDirective.java:202)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visitByHiddingParent(Environment.java:333)
at freemarker.core.Environment.visitAndTransform(Environment.java:413)
at freemarker.core.CompressedBlock.accept(CompressedBlock.java:37)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:2255)
at it.treis.utils.freemarker.CacheDirective.execute(CacheDirective.java:71)
at freemarker.core.Environment.visit(Environment.java:377)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:104)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Macro$Context.runMacro(Macro.java:178)
at freemarker.core.Environment.invoke(Environment.java:700)
at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.MixedContent.accept(MixedContent.java:62)
at freemarker.core.Environment.visit(Environment.java:312)
at freemarker.core.Environment.process(Environment.java:290)
at freemarker.template.Template.process(Template.java:312)
at org.apache.struts2.views.freemarker.FreemarkerResult.doExecute(FreemarkerResult.java:223)
at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:191)
at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:372)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:276)
at it.treis.smartmedia.navigation.interceptors.PrepareParametersInterceptor.intercept(PrepareParametersInterceptor.java:183)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at it.treis.smartmedia.navigation.interceptors.SubscriptionTokenMatcherInterceptor.intercept(SubscriptionTokenMatcherInterceptor.java:52)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.DeprecationInterceptor.intercept(DeprecationInterceptor.java:41)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:168)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:76)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:191)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:73)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.DateTextFieldInterceptor.intercept(DateTextFieldInterceptor.java:125)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:91)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:253)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:140)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:193)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:189)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245)
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:575)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:81)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:209)
at com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:244)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:190)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:317)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)