ISHS Acta Horticulturae 760: XXVII International Horticultural Congress - IHC2006: II International Symposium on Plant Genetic Resources of Horticultural Crops
IDENTIFICATION OF QUANTITATIVE TRAIT LOCI ASSOCIATED WITH YIELD OF TOMATO UNDER HEAT STRESS |
| Authors: | K.H. Lin, H.F. Lo, W.L. Yeh, J.T. Chen |
| Keywords: | Lycopersicon esculentum, heat tolerance, RAPD, ISSR, AFLP, QTL, Marker-assisted selection |
| Abstract:
The optimum temperature range for growing tomato (Lycopersicon esculentum Miller) is 20-26/15-20°C day /night. Heat tolerance of tomato is quantitatively inherited and easily affected by environmental conditions. The objective of this study was to identify the molecular markers linked to heat-tolerance traits in tomato under heat stress. A total of 200 F2 plants derived from heat tolerant CL 5915 crossed with a heat sensitive L4422 were grown in the greenhouse at Chinese Culture University in the summer of 2004. Seven heat tolerance-related traits were scored: flower number, fruit number, fruit set, fruit weight, yield, brix and seed number. The distributions of fruit number, fruit set, flower number, seed number and yield were skewed towards heat susceptibility, characteristics of L4422. Significant positive correlations were observed between yield and fruit weight, fruit number, seed number, fruit set and flower, etc. Polymorphic bands were generated by RAPD, ISSR and AFLP primers using PCR with optimal annealing temperatures. Four linkage groups were constructed with 12 informative markers. Twenty regions on the three groups were detected with QTL for the six traits combined. Some markers were linked to more than one trait suggesting either pleiotropic effects or, alternatively, closely linked genes for different genes. IR845b, IR 814b and IR888g markers may have potential in breeding for high yield and flower number. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
