Allocation of resources to reproduction in Styrax obassia in a masting year. (1/3)
An analysis is presented of three possible pathways of reproductive allocation, namely, allocation of resources to reproductive organs from reproductive shoots, from non-reproductive shoots and from the main trunk. These pathways were examined by comparing the amount of storage starch in reproductive shoots, non-reproductive shoots and the main trunk in Styrax obassia, a typical masting tree species, during a year of little flowering (1999) and in a mass-flowering year (2000). In addition, we measured rates of light-saturated photosynthesis in leaves of reproductive and non-reproductive shoots to examine the contribution of photosynthetic production to reproductive costs. In both the main trunk and non-reproductive shoots the pattern of seasonal variation in the amount of starch did not differ between 1999 and 2000. However, in the mass-flowering year, the amount of starch in the reproductive shoots was less than that in non-reproductive shoots during the growing season. Thus, reproductive shoots bore most of the cost of reproduction, although non-reproductive shoots and the main trunk also bore some of the cost. Mass-based rates of light-saturated photosynthesis of the leaves of reproductive shoots were significantly higher than those of non-reproductive shoots during both the flowering and the fruiting period. However, leaves of reproductive shoots had a significantly smaller area, a lower mass per area, and lower concentrations of nitrogen than leaves of non-reproductive shoots, although the number of leaves did not differ between the two types of shoots. Therefore, the amount of photosynthate per shoot was significantly lower in reproductive shoots than in non-reproductive shoots. These results suggest that the cost of reproduction depends predominantly on storage starch in reproductive shoots, although it is still unclear how much photosynthate is allocated to reproductive organs from non-reproductive shoots. (+info)Phylogeny of Sinojackia (Styracaceae) based on DNA sequence and microsatellite data: implications for taxonomy and conservation. (2/3)
(+info)Anticancer activity of 2alpha, 3alpha, 19beta, 23beta-Tetrahydroxyurs-12-en-28-oic acid (THA), a novel triterpenoid isolated from Sinojackia sarcocarpa. (3/3)
(+info)I apologize for any confusion, but "Styracaceae" is not a medical term. It is a taxonomic category in botany, referring to the family of plants that includes shrubs and trees such as snowbell, sweetshrub, and members of the genera Styrax and Halesia.
In a medical context, you might be referring to various plant-derived compounds found in Styracaceae family plants, which could have potential medicinal properties. For example, styrene, a compound found in the oleoresin of some Styracaceae species, has been studied for its potential effects on cancer cells. However, it is important to note that these studies are still in the early stages and much more research is needed before any definitive conclusions can be drawn about their medicinal applications.