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Eno izmed najpomembnejših orodij molekularnega žlahtnjenja rastlin je genski inženiring, ki vedno bolj pridobiva na pomenu, saj omogoča nastanek rastlin z dobrimi agronomskimi lastnostmi, kot so zadovoljivi pridelki z vrhunsko kakovostjo, odpornostjo na bolezni in škodljivce ter fitosanitarne pripravke. Obstaja mnogo metod, ki se uporabljajo samostojno ali v kombinaciji z obstoječimi metodami žlahtnjenja. Med najbolj uporabljenimi metodami, ki omogočajo spremembo posamezne ali skupine lastnosti so biolistika, elektroporacija in mikroinjiciranje. Te metode je v veliki meri nasledila uporaba t. i. »naravnega genskega inženiringa« ki sloni na prenosu dednega materiala med bakterijo Agrobacterium tumefaciens in dvokaličnicami. Ta metoda je bila v več kot 65 % primerov uporabljena za požlahtnitev agronomsko pomembnih rastlin, ki se tržno pridelujejo. V zadnjih letih pa smo priča razvoju novejših metod za spreminjanje rastlinskega genoma, kot so ZFN – nukleaze z motivi cinkovih prstov, TALEN – nukleaze TAL efektorjev, CRISPR/Cas9 – gruče enakomerno prekinjenih kratkih palindromnih ponovitev s povezanim proteinom Cas9 in ODM – mutageneze z oligonukleotidi. Uvrščene so med najnovejše metode žlahtnjenja rastlin, o katerih trenutno intenzivno razpravljajo različni regulatorni organi v povezavi s tem, ali produkte nastale s temi metodami pokriva obstoječa zakonodaja EU o gensko spremenjenih organizmih in ali jih lahko uvrstimo med obstoječe metode žlahtnjenja z mutagenezo. One of the most important tools of molecular plant breeding is genetic engineering, that increasingly gains in it's importance as it allows the emergence of plants with good agronomic properties, such as satisfactory crops with premium quality, resistance to diseases and pests and phytosanitary preparations . There are many methods that are either used independently or in combination with already existing breeding methods. Among the most used methods, which make it possible to change a particular single property or a groups of properties are biolistics, electroporation and microinjection. These methods were largely followed by the use of a »natural genetic engineering« based on the transfer of the heritable material between the bacterium Agrobacterium tumefaciens and dicotyledons. This method was used in more than 65 % of the plant breeding cases for the regeneration of agronomically important plants that are market cultivated. In the last years however we are witnessing the development of newer methods for genome editing of plants, such as ZFN – zinc finger nucleases, TALEN – transcriptional activator-like effector nucleases, CRISPR/Cas9 – clustered regularly interspaced short palindromic repeat, CRISPR-associated nuclease and ODM – oligonucleotide-directed mutagenesis. They are categorized as the newer breeding methods that are currently being discussed intensively by various regulatory bodies in relation to whether products produced by these methods cover existing EU legislation on GMOs and whether they can be classified as already existing methods of plant breeding with mutagenesis. |
