In the PipelineResearch
Development of a broad spectrum disease resistance for citrus
The focus of this research is to manipulate Calcium signals in citrus to accomplish broad spectrum disease resistance and abiotic stress tolerance. Our preliminary results are very encouraging with one of our transgenic plants showing resistance to one bacteria, two fungi and one fungal toxin.
Transient sparks in cytosolic calcium (cy-Calcium) concentration has profound effects in many cellular processes in all living organisms. In plants, cy-Calcium sparks is an early event in defense signaling and plays important roles in activating the plant’s surveillance system against attempted microbial invasion and abiotic stresses. Calcium concentration modulation in the cytosol is a very dynamic process involving organelles, including mitochondria and endoplasmic reticulum (ER). Mitochondria can sequester large amount of cy-Calcium, functioning as a storage place to later release, regulating the rise and increases in cy-Calcium, and reloading the ER. Calcium signals are specific for each particular stimulus, varying in amplitude, duration, frequency, and location. The specific signal characteristics are well orchestrated by the organelles, particularly the mitochondria, which through ATP regulates the frequency and duration of channel opening, being therefore a modulator of calcium signaling. For each specific calcium signal, there are combinations of calcium sensors and target proteins downstream that function as decoders for the signals.
Other Projects
Isolation and molecular characterization of genes involved in calcium signaling.
We are using microarrays and 2-D protein analysis to isolate sensors and effectors correlated with the plant's response to pathogens and abiotic stresses. The genes will be used for plant transformation.
Development of new improved citrus cultivars
This is a long term research project to develop improved cultivars of orange, grapefruit, lemons and pummelos . We are field testing several potential improved cultivars developed in our lab, including an excellent seedless lemon. and a seedless white pummelo. We are currently patenting a new red grapefruit variety with darker red skin and flesh than the Rio Red garpefruit. Photos are shown elsewhere in the home page.
We are routinely using genetic transformation by Agrobacterium to introduce genes into citrus species. Several constructs are being engineered with new genes for genetic transformation. All genes are from citrus to minimize problems of public acceptance.