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Rastline komunicirajo med seboj s sproščanjem molekul v atmosfero in rizosfero. Zadnji poskusi kažejo, da lahko obveščanje med rastlinami poteka tudi po skupnem mikoriznem spletu oz. skupnem miceliju v tleh. Je bolj učinkovito in neposredno kot signaliziranje po zraku. Proces sporazumevanja po skupnem miceliju lahko sproži obrambne mehanizme v rastlini proti več biotskim stresorjem, kot so rastlinojedi insekti, foliarne nekrotrofične glive in mehanske poškodbe. Po skupnem miceliju se prenašajo obrambni signali, ki jih sprožijo rastline, ki jih napadejo rastlinojedi ali so okužene s patogeni, do sosednjih rastlin, še preden so slednje napadene ali okužene. Obstajajo trije potencialni mehanizmi sporazumevanja med rastlinami po skupnem miceliju, najpogostejši pa je transport signalnih molekul po citoplazmi hif. Izvor signala je za zdaj še neznan. Ugotovili so, da se rastline, ki prejmejo signal, odzivajo s produkcijo metil salicilata in jasmonske kisline. Za identifikacijo teh molekularnih struktur signalov so potrebni zelo zapleteni in nadzorovani poskusi. Učinkovitost signalov, ki se prenašajo po skupnem miceliju, je odvisna od hitrosti signala in časa, po katerem se pokaže odziv na signal v sosednji rastlini. Prav tako pa je pomembna tudi razdalja, ki jo lahko signali premagajo in na koliko prejemnih rastlin lahko vplivajo. Poznavanje vloge skupnega micelija v sistemu arbuskularna mikorizna gliva–rastlina–škodljivec, je pomembno za splošno razumevanje delovanja ekosistemov. V ekološkem kmetijstvu pa imajo te interakcije potencial za varstvo rastlin pred škodljivci. Plants communicate with each other through production of molecules released into the atmosphere and rhizosphere. Besides, the latest experiments demonstrated interplant communication via common mycelial networks in the soil. Common mycelial network offers a potentially more effective and directed pathway of defence compared to the aerial pathway. It has been suggested that the process of forming mycorrhizas itself prepare plant defences against multiple biotic challenges (such as insect herbivores, foliar necrotrophic fungi and mechanical damage). These networks can transport signals produced by plants in response to herbivore and pathogen infestation to neighbouring plants before they are themselves attacked. There are three possible mechanisms by which common mycelial networks enable interplant signalling, but the most common is delivery of signal molecules via cytoplasmic streaming within hyphae. The nature of the signal is unknown, but this far, the key responses of receiver plants are production of methyl salicylate and jasmonic acid signalling pathways. However, identifying the molecular structure of signals will require extremely challenging controlled experiments. The impact of common mycelial networks-based warning signals will depend on their speed and the period of time over which their effects are manifested, at least as important is the physical distance over which they can travel and how many receiver plants they can affect. Understanding the role of common mycelial network in complex arbuscular mycorrhizal fungi–crop–pest interactions is important for general understanding of ecosystem functioning. It poses a considerable challenge in designing agricultural management systems that ultimately lead to pest tolerance. |
