Project Number: WVA00406
CRIS Number: 0180505
Multi-State Project: NE-9
CONSERVATION AND UTILIZATION OF PLANT GENETIC RESOURCES
Investigators: Arora, R.
Performing Department: Plant & Soil Sciences -- 1825
Start Date: 10/01/1998
Termination Date: 09/30/2003
Reporting period: 01/01/2001 to 12/31/2001
Progress Report:
In previous research, we assessed genetic variation for cold hardiness (CH) in a segregating F2 population derived from a super cold hardy (R. catawbiense) x moderate cold hardy (R. fortunei) cross. The objective of this study was to identify DNA markers that are linked to and cosegregate with the CH trait in these populations using bulked segregant analysis (BSA). We used 7-8 F2 progeny comprising the `tails' of the hardiness distribution, which resulted in two bulks separated by an average 14.7 degrees C in CH phenotype. RAPDs were used to compare for presence vs absence differences in our CH bulks. Data indicate a 800 bp band from primer UBC #29 to be present more often in the 'low' cold-tolerance bulk than the 'high' bulk, suggesting that this marker is associated with genes from the less hardy R. fortunei parent. Interestingly, these results illustrate a case where selection of super cold hardy offspring could result from selecting against the presence of this DNA marker. Our data also indicate that in selecting those 15 progenies for cold hardiness using presence/absence of this marker as a predictor, there is a 63 % chance (11/15) of making a correct assignment, and a 27% probability (4/15) of making an incorrect one.
Publications:
Lim, C-C, R. Arora and S.L. Krebs. 2001.Tagging genes for cold hardiness in Rhododendron. HortScience 36:582
Impact:
From a practical standpoint, using DNA markers to predict cold hardiness is a highly useful tool that can assist breeders in making selections in breeding programs to improve rhododendron cold hardiness.