Regeneration in selected Cucurbita spp . germplasm

A system for plant regeneration from individual cells or explants is essential for the application of genetic engineering. In Cucurbitaceae, in vitro regeneration has been reported across a wide spectrum of crops, including summer squash (Cucurbita pepo L.) (7), winter squash (Cucurbita maxima Duch.) (9), bottle gourd (Lagenaria siceraria Standl.) (6) and, recently, figleaf gourd (Cuburbita ficifolia Bouché.) (8). Genetic transformation was applied in this family for different purposes, for example to improve several cucurbits with potential to function as rootstocks (4, 6, 11). Regeneration ability is highly influenced by genotype, and then it is necessary to develop and adjust the appropriate regeneration protocols for each cultivar. In this work we assay different in vitro conditions useful for regeneration in eight Cucurbita cultivars which presented interesting characteristics for breeding. They include: three C. pepo, two C. ficifolia one C. maxima and two C. moschata species. To the best of our knowledge this is the first study reporting in vitro regeneration for the latter species.