TABLE 1.
Schizaphis graminum genotypes examined using 2-D DIGE for proteins associated with CYDV-RPV transmission competency, their CYDV-RPV transmission types, and their transmission barriers
| Genotypea | Sourceb | RPV transmission phenotype (% transmission efficiency)c | RPV transmission barrierd | Refractive typee |
|---|---|---|---|---|
| Sg-F | Parent | Competent (63) | None | |
| A3 | F2 | Competent (100) | None | |
| CC6 | F2 | Competent (75) | None | |
| Sg-SC | Parent | Refractory (1) | ASG, HG | RT-3 |
| K2 | F2 | Refractory (<1) | ASG, HG | RT-3 |
| MM1 | F2 | Refractory (<1) | ASG, HG | RT-3 |
| C2 | F2 | Refractory (3.6) | HG | RT-1 |
| CC1 | F2 | Refractory (<1) | HG | RT-1 |
| K3 | F2 | Refractory (4.3) | ND | RT-ND |
| BB1 | F2 | Refractory (<1) | ASG | RT-2 |
The name of the S. graminum genotype as it is maintained in the USDA-ARS Virology and Nematology Facility on the campus of Cornell University, Ithaca, NY.
The sources of the S. graminum genotypes used in this study were the parental genotypes Sg-F (transmission competent) and Sg-SC (refractive) and selected F2 lines from random matings of F1 hybrids.
Characterization of the CYDV-RPV transmission phenotype, used for the purpose of grouping in the statistical analysis of the 2-D DIGE experiments. Transmission-competent genotypes all had >60% CYDV-RPV transmission efficiencies, and refractory genotypes had <5% CYDV-RPV transmission efficiencies.
For the refractory genotypes, the barriers to transmission, i.e., the hindgut (HG) and the accessory salivary gland (ASG), have been characterized for the genotypes as indicated. ND, the barriers have not been determined.
RT-1 genotypes possess a strong gut barrier and can transmit viruses across the ASG, RT-2 genotypes possess a strong ASG barrier and can acquire viruses into and across the gut epithelium, and RT-3 genotypes possess a dual barrier to transmission.