Research On Seed Germination And Rapid Tissue Propagation System In Endangeredplan Haplophyllum Tragacanthoides Diels

Haplophyllum tragacanthoides Diels is part of the Rutaceae intends Ruta (Haplophyllum) perennial xerophytic dwarf shrubs. Endemic to China, it belongs to the protecting plant of national level three, level one in arid region of northwest and Inner Mongolia. The flowers of the species was bright yellow color with long flowering period and it is an important desert flower resources and it has some medicinal value. Reproductive rely mainly on seedlings to achieve, so doing studies about seed germination characteristics, stress and others to provide breeding base in seedling establishment. Meanwhile, establish the kind of rapid propagation techniques can get a lot tissue culture seedlings detoxification in a short period. It can provide a theoretical basis for the protection of rare and endangered plant germplasm, introduction and domestication. Research indicates:1. Haplophyllum tragacanthoides Diels is a light-inhibited seeds and Illumination restricts seed germination at the beginning stage; temperature has a wide suitable range of the seeds, the seeds under variable temperature conditions of 20℃ or 15℃/25℃ are best for germination;The growth of seed germination and seedling was significantly inhibition with the increasing of drought stress. Light and water in the seed stage may be the major factors make it an endangered plants in desert regions.2. The physiological parameters changing under water stress of Haplophyllum tragacanthoides Diels are:MDA, proline and soluble protein content showed an increased trend with the increasing of drought degree and the maximum value reached by the concentration respectively 1.45μmol·g-1、55.00μg·g-1、41.65mg·g-1 of PEG at 30%; the activity of SOD, POD and CAT activity showed a trends increased first and then decline with the increasing of concentration of PEG, the three trends not the same, the coordination of the three kinds of enzymes adapt to adversity.3. Aseptic hypocotyl and leaves of Haplophyllum tragacanthoides Diels are used for callus induction. As compared to hormones of 2,4-D and NAA, the treatment with 6-BA showed highest callus rate, higher than 90%,2～3d earlier than other treatments, under the treatment used same kind of growth hormone, cotyledon has a better callus rate and callus texture compared to hypocotyl.4. Leaves of Haplophyllum tragacanthoides Diels are used as explants, the optimal medium for callus induction is:MS+6-BA1.40mg·L-1+2,4-D 1.30mg L-1;the optimal medium for wound tissue differentiation is:MS+6-BA1.00mg·L-1+NAA 1.10mg L-1;the optimal medium for differentiation of axillary buds is:MS+6-BA 2.1 Omg L-1+KT 1.00mg·L-1+NAA 0.45mg L-1; the optimal medium for the proliferation of axillary buds:MS+IBA 0.50mg·L-11+NAAO.10mg·L-1; the optimal medium for rooting is:MS +IBA 0.70mg L-1+NAA 0.05mg·L-1; selection of different substrate is subjected to transplanting hardening of Haplophyllum tragacanthoides Diels,results show that the survival rate up to 70% by using humus as a substrate in the process of transplanting seedlings,so the humus can be the first choice used as the preferred substrate.