Location: Application Technology Research2012 Annual Report
1a. Objectives (from AD-416):
The objective of this cooperative project is: 1) to determine the differences in the expression of genes and proteins in plants grown in a greenhouse environment (no UV-B) compared to those in 'field conditions' (normal ambient UV-B concentrations), and 2) to identify the protein and genetic changes during hidden hunger, and using this information, deveolop a technique that growers can use to test their plants for specific and/or general nutrient deficiencies.
1b. Approach (from AD-416):
Microarray techniques will be used to rapidly screen for global differences in gene expression between the two different UV-B environments and nutrient (i.e., N,P,K,Fe,B, and Mg) stress. The initial use of an existing model plant system (i.e., Arabidopsis thaliana) for this work will facilitate identification of specific genes that are responsive to the absence of UV-B during growth. After identifying such UV-B and nutrient stress responsive genes in Arabidopsis, we can then identify related genes in bedding plant species (i.e., impatiens, petunia, begonia, geranium, marigold, pansy, chrysanthemum, and New Guinea impatiens). Simultaneously, proteomics techniques (i.e., identification of proteins of interest by 2-D gel analysis, followed by protein sequencing) will be used to screen for global differences in protein expression between the two different UV-B environments.
3. Progress Report:
Over the previous year, several antibodies were developed and refined, which will be used as indicator markers for the presence of proteins in targeted plants. An antibody and companion ELISA assay was developed for an iron metabolism protein, Fro1 (one of the two main iron uptake proteins in non-grass species). The analysis is nearly complete for the development of an antibody to the second main iron uptake protein in non-grass species, Irt1. An antibody and companion ELISA assay was developed for a second boron metabolism protein, Nip5. Previously, one was developed for the boron metabolism protein, Bor1. Nip5 and Bor1 are the two main plant boron uptake proteins. The analysis was completed for the development of an antibody to a first nitrogen metabolism protein, Nrt1, one of two main uptake proteins for nitrate nitrogen (one of two main forms of nitrogen used by plants). Analysis was partially completed for the development of antibodies to a second and third nitrogen metabolism protein, Nrt2 and Amt1, respectively. Nrt2 is the second main nitrate transport protein, and Amt1 is the main ammonium transport protein (ammonium is the second main form of nitrogen used by plants). Together, this group of antibodies should provide a clear picture of nitrogen uptake being far more comprehensive than current methods of evaluating nitrogen uptake. This project relates to objective 1B of the parent project: Develop new, inexpensive, non-destructive methods to monitor plant growth and stress. Provide rapid, onsite capabilities to test nutrient status of plants, nutrient solutions, and run-off to supplement pH and electrical conductivity information. Apply existing sensor technologies in novel ways to monitor biotic and abiotic plant stress.