Citrus Psorosis Virus Coat Protein-derived Construct Confers Resistance in Citrus against Psorosis

Citrus psorosis virus (CPsV) is the causal agent of psorosis, a serious and widespread citrus disease. Two syndromes of psorosis, PsA and PsB, have been described, with PsB being the more aggressive form. A previous study had reported pineapple sweet orange plants transformed with a hairpin construct from the CPsV coat protein gene (ihpCP). Some of these plants were resistant to a PsA isolate.

A. De Francesco from the Instituto de Biotecnología y Biología Molecular in Argentina recently found that expression of the ihpCP transgene and siRNA production in two previously developed lines, ihpCP-10 and ihpCP-15, were stable with time and propagation. Particularly, the line ihpCP-15 has been resistant for more than 2 years, even after re-inoculation.

Line ihpCP-15 manifested complete resistance while line ihpCP-10 was tolerant to the virus, showing delay and attenuation in PsB symptoms. The ihpCP plants were also resistant against a heterologous CPsV isolate that causes severe PsB syndrome.

These lines could be promising for the development of biotech product aimed at controlling psorosis. 

For more on this study, read the article in Transgenic Research.