Reduced Indexing Time for Cachexia and Exocortis Diseases in Citrus

Abstract:

The influence of three vigorous rootstocks (Cuban shaddock, rough lemon, and Volkamer lemon), gibberellic acid, and foliar urea sprays on the expression of exocortis and cachexia symptoms on indicator plants were evaluated. Cuban Shaddock proved to be the best rootstock for symptom expression on Clemeline 11-20 and Arizona 861 S-1 citron indicator plants for cachexia and exocortis, respectively. Application of 0.5% foliar urea sprays, alone or combined with 20 ppm gibberelic acid promoted better symptom expression for cachexia than the unsprayed control. Exocortis and cachexia are viroid diseases found throughout the citrus regions of the world including Cuba. Although different indexing methods are known for these two pathogens, the one most commonly used method is the bioassay method which is time-consuming (1, 3). It may be possible to reduce indexing time by selection of hosts which allow greater pathogen multiplication. This report describes our results of several trials done with the objective of shortening the biological indexing period and, thus, decrease the indexing costs under Cuban conditions. The influence of three vigorous rootstocks, gibberellic acid (GA3), and foliar urea sprays on symptom expression of cachexia and exocortis on Clemeline 11-20 and Arizona 861 S-1 citron indicator plants were evaluated. The viroid detection method

Año de publicación:

2000

Keywords:

Fuente:

google