Fitotoxinlerin Bitki Hastalıklarındaki Rolü

Bacterial and fugal plant pathogens are known to produce toxic subtance in infectected plants, Which are named as phytotoxins. Phytotoxins are small molecules and have a variety of structures including sesquiterpenoids, sesterterpenoids, diketopiperazines, peptides, spirocyclic lactams, isocoumarins, polyketides, tetramic acids and perylenequinones. Phytotoxins may be classified as host specific toxins (HST) and non host specific toxins (NHST). Host specific toxins affect only plants of a genotype susceptible to the pathogens. On the other hand, non-host specific toxins affect a lot of plants. So far, Approximately 23 HST and 34 NHST have been determined. All of HSTs are produced by fungi, many of Which belonging to Alternaria ve Cochliobolus. NHSTs produce both bacteria and fungi. Phytotoxins cause a wide range of simtomps on host plants including wilt, chlorosis, blights, leaf spots, necrosis, water soaking and galls.