ISHS Acta Horticulturae 522: XXV International Horticultural Congress, Part 12: Application of Biotechnology and Molecular Biology and Breeding - General Breeding, Breeding and Evaluation of Temperate Zone Fruits for the Tropics and the Subtropics.
BREEDING PAPRIKA TYPE PEPPERS RESISTANT TO PHYTOPHTHORA CAPSICI |
| Authors: | M.E. Candela, C. Egea, M.D. Garcia-Perez, J. Costa, M. Candela |
| Keywords: | Phytophthora capsici, breeding, Capsidiol, Pepper, resistance |
| Abstract:
We present the first results of an improvement programme to obtain peppers cultivars for paprika production with a sufficient degree of hardiness to be cultivated in calcareous soils and little available water, which produce an intensely red fruit and which are resistant to Phytophthora capsici. The genetics of resistance to the pathogen were studied by crossing a sensitive parent, cv. Americano (A), possesing the desired agronomic characteristics, with one resistant parent Serrano Criollo de Morelos (SCM), wild type of no agronomic value. The biochemical parameters marking resistance were analysed by using the pepper phytoalexin Capsidiol in order to accelerate the improvement programme. Three month old plants were infected by decapitation of the stems and application of discs of fungal mycelium. The necrotic zone of these stems and the area immediately adjacent were then analysed for Capsidiol production. The results obtained to date show that in F1 the most suitable cross was A x SCM, using the sensitive cultivar as mother. Material selection from the F2 population was made on the basis of their resistance to the fungus and the similarity of their fruit with that of the cultivated species. The most probable model which can be proposed establishes a polygenic and probably multicomponent inheritance. Capsidiol is seen to be an ideal marker of resistance when evaluated in relation with the length of necrosis in decapitated stems innoculated with the fungal mycelium. | |
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