Variability of Seed Traits in Interspecific and Intergeneric Combinations between Different Genotypes of Cactaceae

Abstract

Based on aesthetic considerations of cacti plants and the germination capacity of the pollen grains (more than 30%), 19 genotypes of cacti (including Aylostera narvaecensis, A. buiningiana, Rebutia kupperiana var. spiniflorum, R. donaldiana) have been used in a cyclic cross-pollination pattern. Fruits and seeds obtained from 24 interspecific and intergeneric combinations were analyzed by studying their main traits. The highest weight was registered for fruit belonging to R. pseudodeminuta var. schumaniana x R. senilis (23.3 mg) and A. buiningiana x A. vallegardensis (20.4 mg). The coefficient of variability for fruit weight had a large amplitude, between 12.3% (A. spinosissima x A. albiflora) and 98.4% (A. favistyla x A. archibuinigiana). The fruits belonging to A. muscula x A. vallegardensis were registered with the highest value of number of seeds/fruit (93.2). In the cross between genera, the greatest value of fruit weights mean was registered on R. senilis x A. archibuinigiana (29.2 mg) and R. cajasensis x A. muscula (23.1 mg). Peculiarities of the fruits and seeds resulted from intergeneric combinations presented closer connections than interspecific ones. The phenotypic traits of fruits and seeds did not influence the seeds germination, but germination was clearly influenced by compatibility between genitors.