There is no effect of antibiotics, which act on cell walls, e.g., Penicillin, Vancomycin, but antibiotics which have got effect on biochemical reactions may prevent the effect of Mycoplasma by preventing their growth, e.g., Tetracycline.
When the Cuscuta, which is a total stem parasite, takes food from a plant infected by Mycoplasma, the organisms enter into the parasite. When this infected parasite attacks healthy plant, the Mycoplasma enters into that plant and causes infection.
Mycoplasma is the smallest and simplest prokaryotes, discovered by Louis Pasteur (1843) from cattle suffering from pleura-pneumonia, hence were called as pleura-pneumonia like organisms (PPLO).