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Due to droughts and water shortage in Mendoza Province (Argentina), urban green areas have been reduced with the consequent decrease in landscape quality. Replacing exotic plants with native, less water consumers, could make landscaping more sustainable. Lack of information and low availability in nurseries is a limiting factor. Sphaeralcea genus, native from arid and semiarid regions of America, is characterized by a brilliant, profuse and prolonged flowering. In this work we evaluate the potential of Sphaeralcea miniata and Sphaeralcea mendocina to obtain commercial cultivars. Variation of ornamental traits and commercial propagation were studied. Six populations were evaluated, flower and leaf samples were collected, seeds of both, autopolinated and open pollinated plants were cultivated in the nursery. Seed stratification and scarification techniques and rooting in stem cuttings were evaluated. Phenotypic variation in flower and leaf traits was found, this variation was found between and within populations and in the offsprings. Germination did not exceed 60%, probably due to physical rather than physiological dormancy. 60 to 68 % rooting of cuttings was obtained. The natural variation in ornamental traits is an indicator of the possibility to obtain different cultivars. Superior genotypes could be propagated by rooted cuttings. New research is necessary to improve seed germination.

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The lines used for onion hybrid production are partially homozygous due to the existence of endogamy depression during selfing. The production of haploid plants through in vitro gynogenesis, and later chromosome doubling allows reaching complete homozygosis. There are several factors that influence onion gynogenesis like, the genotype of the donor plant, the conditions and media of the growth culture. The duplication of chromosome number is a necessary step once obtained the haploid embryos, because spontaneous doubling is very low. There are several antimitotic substances that can be used for chromosome doubling, among them colchicine and APM, both with 70 % of efficiency, and others like oryzalin and trifluralin. The principal factors that affect doubling techniques are: the explant type, the antimitotic substances used, the duration and conditions under which the treatments are performed. For these reasons is necessary to optimize the duplication methods adjusting the concentration used and the duration of the treatments. This technique step represents today one of the main constraints for use in the improvement plans.