Abstract: The present invention relates to the generation of transgenic plants resistant to infections caused by microorganisms restricted to the phloem, and it comprises the induction of the expression of a chimeric or fusion protein, which comprises a phloem protein of Citrus aurantifolia (CsPP16), a linker protein and a protein with antimicrobial activity; for example, with antibacterial activity or antibacterial hydrolytic enzyme. The portion of the fusion protein corresponding to the CsPP16 protein can exert its function of simplasmic movement, which occurs via the plasmodesmata of the plant to reach the phloem sieve tubes, while the antimicrobial portion can act to eliminate the microorganism, which settles in the phloem. The invention allows controlling the disease that causes the citrus yellowing or Huanglongbing (HLB), also applying to the treatment of other diseases caused by bacteria and other microorganisms that settle in the vascular tissue of higher plants.