Allometric Scaling Expoents And Plant Interactions Regulated By Sensitivity To ABA In Arabidopsis Thaliana

Recently years, plant interaction and allometric scaling relationship or self-thinning are focused. Abscisic acid (ABA) can trigger and regulate germination, growth, development, defense, response to stress, and reproduction in plants. However, it is still unclear how ABA affected the plant interaction and allometric scaling relationship or self-thinning. Fortunately, a series of ABA sensitivity mutations provide well experimental material to test this idea because these changes were induced by mutation of the ABA locus. Hence, the effects of sensitivity to ABA on the power of allometric scaling or self-thinning and plant interaction were studied with two Arabidopsis mutants (abi1-1, insensitive to ABA and era1-2 hypersensitive to ABA). The main results are as below following:(1) The experimental results showed that the self-thinning power of abi1-1 (-1.49) was smaller than that of wild type (-1.35), and the self-thinning power of era1-2 (-1.21) was greater than that of wild type. Two parameters of resource utilization (l mean height from root to leaf; a total area of leaves) were more advantageous to era1-2 than to abi1-1 under density stress. Physiological indices of light use (photosynthetic rate, photosynthesis index PSI), water loss (transpiration rate, stomata area index SAI), and water-use efficiency (photosynthetic rate/ transpiration rate) of abi1-1 and era1-2 were consistent with the resource utilization parameters of these Arabidopsis mutants. It can be concluded that the different self-thinning power of the two Arabidopsis mutants resulted from their different resource utilization (such as light and water use) in response to density stress.(2) The allometric relationships between plant biomass production rates and different measures of body size (dry weight and length), and plant interactions were reported for two mutants of Arabidopsis thaliana (abi1-1 and era1-2). Data showed the scaling relationships, such as daily rates of growth (G) and body mass (M), plant body length or plant height (L) and body mass (M), photosynthetic biomass (Mp) and nonphotosynthetic biomass (Mn), and, daily rates of growth (G) and photosynthetic biomass (Mp) were significantly different in abi1-1 and era1-2. It is also showed that the relationship between relative interaction intensity (RII) and body mass (M) was different...