Study On Adaptational Anatomical Structure Of Nutritive Organs And The Salt-tolerance Physiology In Two Species Of Limonium

Limonium. Gmelinii (Willd.) Kuntze and Limonium. Otolepis (Schrenk) Kuntze are recretohalophytes belong to Plumbaginaceae Limonium. In this essay, investigated the salt tolerance of two recretohalophytes in two aspects of microstructure and physiological indexes. The results of research could supply some information for establishing estimate indexes of salt tolerance of plants in order to filtrating resources of halophytes of Xinjiang and empoldering saline soil.The salt resistant structural characteristics of two species of Limonium were defined. The typical characteristics that a lot of salt glands distribute in epidermis of leaves and caulis . The arranged compactly epidermal cell had thick keratose layer and the thickness increment external tangential wall of epidermis cell which propitious to reducing water evaporation; There are well-developed aerenchyma foxming many air passages in cortex of roots is advantageous to the transport and store of oxygen, and so on.Moreover, there were some other structures that had not direct relationship with salt resistant function, but they enhanced the tolerance of the p lant through increasing the abilities of assimilating, transporting and sustaining.The seedlings of L.gmelinii and L.Otolepis were treated with different concentrations of NaCl .The results of physiological indexes showed that cell membrane permeability (CMP) of two species increased along with the increasing of NaCl concentration, and concentrations of proline(Pro), soluble sugar (SS), dissociative amino acid(AA), organic acid(OA) and malondialdehyde(MDA) showed the same tendency. The concentrations of chlorophyll (CHl) of two species decreased as the stress intensity extended, CHl a/CHl b value reduced when salt stress increased; the Superoxide dismutase(SOD) activity of two species increased along with the increasing of NaCl concentration. fleshy of two halophytes were increased firstly, and then gave a decreasing tendency when stress intensity extended.Seeds of L.gmelinii and L.Otolepis were germinated 9 days at different temperature regimes in different concentration NaCl solution and iso-osmotic PEG. According to the germination percentage, germination potential , germination index and the germination recovery percentage of seeds that were incubated in NaCl and PEG solutions for 9 days recovered after being transferred to distilled water. We can conclude that: A temperture regine of 15℃night and 25℃day yielded optimal germination. Germination p was highest in the distilled water. The germination percentage, germination potential and germination index increased along with the reducing of NaCl and iso-osmotic PEG concentrations, that had inhibitory effect on the germination of seeds. The inhibitory level of PEG as much as that of iso-osmotic NaCl.