Scientist shooting citrus green disease
Published:Thursday | March 8, 2012 | 12:00 AM
SOME 13 scientists drawn from the University of the West Indies, Scientific Research Council and Ministry of Agriculture and Fisheries will today complete a shoot tip grafting training course conducted by Dr Olga Mas Camacho from Cuba. The purpose of the three-week course is to increase local capacity to manage the devastating citrus green disease and provide disease-free citrus planting material.
Developed in 1975, shoot tip grafting is a laboratory process which has proven to be very successful producing pathogen-free citrus. It involves cutting the microscopic growing tip of a young shoot and grafting this to an incision in a toothpick-sized seedling.
Dr Lisa Myers Morgan, senior research director at the Montpelier Research Station, told AgroGleaner that the plan to have persons from different agencies trained in this technique was deliberate.
"This is to ensure that the capability of doing this will reside in more than just the ministry of agriculture, and the technology (shoot tip grafting) has been known to be very effective in producing clean citrus planting material," disclosed Myers Morgan.
Cause of disease
Citrus greening is caused by a bacterium known as Candidatus liberibacter asiaticus that is transferred from plant to plant primarily by piercing-sucking insects called psyllids. As the bacterium multiplies it chokes off the supply of nutrients, moving throughout the plant, weakening the plant and eventually killing it.
Myers Morgan explained that under the citrus certification programme started in 2002 in an effort to curtail the impact of the citrus tristeza virus, some strains of citrus, including tangerine and silver cluster grapefruit, were excluded. The work to be undertaken will include 'cleaning up' these citrus crops, both of which have good economical potential, as well as ensuring that there is enough clean planting stock of the more popular Velencia and Parson Brown varieties of orange.
Other duties
In addition to the training, Dr Camacho is mandated to produce, at least, viable clean shooting tip cultivar (plant) of the seven selected citrus varieties. Another consultant will arrive later in the year to continue this work by transferring these to more vigorous rootstock to allow them grow faster.
Myers Morgan advised that because of the need for ensuring that the final material is absolutely clean the process can be lengthy, and expectations of a quick fix are unrealistic. "Some of the tests can last as long one year. In this case, we are looking at almost two and half to three years before that material can be realised," she stated.
In the meantime, citrus plants are already under protected cover at Bodles Research Station and, therefore, are not exposed to the citrus greening pathogen and will be tested to ensure that they are clean. Material from this inventory will be made available to the citrus industry for planting.