Effect of cell size and growing medium quality on the commercial productivity of Limonium sinuatum plants

Abstract The plug cell volume and the quality of the growing medium during nursery stand out as the most important factors affecting the success of ornamental plants, because they significantly affect biomass accumulation and post-transplant yield. These two technological inputs may also be a source of potential abiotic stress capable of modifying the grower´s profit. The aim of this work was to evaluate the physiological mechanisms involved in the growth of Limonium sinuatum plants in three different pre-transplant plug cell volumes and two different growing media as well as in their transplant to pots or to an amended soil. The hypothesis tested was that the negative effects of these combined abiotic stress sources could limit L. sinuatum growth and yield. Our results showed that, in response to limiting situations of root growth, L. sinuatum plants modified the expanded leaf area, the accumulation of fresh-dry weight and the partitioning of photo-assimilates. The physiological processes identified include the capacity for leaf initiation and expansion, the photosynthetic capacity, the growth rate per unit area and time, and the partitioning of photo-assimilates between different plant organs. Since these responses to different types and degrees of abiotic stress are similar to those found in plants depressed in endogenous cytokinins, we speculate that these hormones may be involved in the results obtained in this work.