Adaptability of Bruguiera Sexangula Seedlings to the Interaction between Tide-Flooding and Salinity

摘要

The Bruguiera sexangula seedlings were treated with interaction between tide-floodling and salinity using automatic tide simulation equipment in a greenhouse for 130 days. The time of flooding implemented with three gradients of 4, 8, 12 h.d-1and water salinity with three gradients of 5, 15, 20‰. The growth morphological characteristics, growth, biomass, photosynthetic rate, chlorophyll content, root vigor and other resistance physiological indexes were determined. The results show that, flooding time and water salinity had significant effect on most of the growth indexes except the number of leaves, but their interaction was not obvious, for it only had large effect on the width of leaves. Flooding time and water salinity all have significant effect on chlorophyll, root vigor and net photosynthetic rate, but their interaction only have significant effect on net photosynthetic rate. Flooding time and water salinity all have significant and even extremely significant effect on the length of the aerial root and the number of fine root of ruguiera sexangula seedlings, but their interaction has no significant effect on the length and number of the aerial root, or the length and number of taroot, or the length and number of fine root. Principal component analysis of 10 indexes of the growth information shows that the optimum treatment combination is flooding with 4-8 h.d-1and salting with 5-15‰.