Biological Characteristics And Storage Eco-physiology Of Ormosia Hosiei And Ormosia Xylocarpa Seed

Ormosia hosiei and ormosia xylocarpa are precious tree species of the ormosia genus, legumes family.They have a set of economic, social, ecological and scientific value. However, due to people irrational use and weak protection awareness for them, resulting in sharply decline in population size and habitat quality. This leads to resource situation is quite grim. Therefore, it is necessary to expand the population through artificial propagation and reduce the destruction of existing resources. Tree seed biological characteristics and eco-physiology characteristics of the storage directly affect reproductive update wild populations and artificial breeding. Therefore, to carry out tree seeds biological characteristics and storage eco-physiology research is an important part of seed ecology. We first studied the biological characteristics of ormosia hosiei and ormosia xylocarpa seeds,to explore their morphology, component,germination and hard seed characteristics, the relationship of hard seeds and vitality. These will provide a theoretical basis and guidance for artificial cultivation and gremplsm resources protection of ormosia hosiei and ormosia xylocarpa. Using ormosia hosiei and ormosia xylocarpa as research materials, we adopted three treatments method including room temperature storage, low temperature drying storage and room ultradrystorage, and regularly measured the change of germination rate, storage material and the physiological and biochemical substances of storage seed for find the best storage way. These resuts will provide a reliable basis for the prolong storage life and germplasm conservation of ormosia hosiei and ormosia xylocarpa seeds. Through two years of research, we obtained the following conclusions:Each one thousand seeds of ormosia hosiei and ormosia xylocarpa weight respectively are 1029.72 g and 194.45 g. The ormosia hosiei seeds belong to large seeds,and the oformosia xylocarpa seeds belong to middle seeds,theirs water content are respectively 13.98% and 11.45%,their seeds both belong to orthodox seeds. The hardseed percentage of Ormosia hosiei and ormosia xylocarpa are as high as 86% and 88% respectively, typically belong to hard seeds. The seeds of ormosia 4 hosiei and ormosia xylocarpaare not only have rich protein, fat and polysaccharide compounds, but also have ketone and alkaloids substances.The seeds bibulous rate of ormosia hosiei and ormosia xylocarpa show trend that after rising then stable trend with the absorption water time, their bibulous rate of broken skin seed is higher of 147% and 84% respectively than full seeds.Hard and dense seed coat of seed is the important factors that affect seed imbibition. By scanning electron microscopy observation for the seed coat of ormosia hosieiand ormosia xylocarpa, we discovered the hard seed overlying a layer or layers dense, shiny wax substant. The surface of seed coat composed of closely packed stone cell. These wax substant block water intrusion. The electron microscopic scan results of seed coat section show that the seed coat composed of stratum corneum, testa and endotasta three parts. Testa is palisade tissue cell, longgitudinal closely packed.The palisade tissue cells of closely stratum corneum harden,with umpermeability, are some stone cells. Endotasta composed of parenchyma cells, with loose organization and strong water obsorbing capacity. The hard seed by hot water and concentrated sulfuric acid treatment havecracks and holes in surface, palisade tissues ranged loosely. The parenchyma cell layer of seed coat absorb water and make the hard seed imbibition through these cracks and holes. The methanol extraction contents of Ormosia hosiei seed seed coat and embryo significantly inhibited cabbage seed germination,and the effect of methanol extraction contents of Ormosia xylocarpa seed coat to seed germination of Chinese cabbage was not obvious,but the embryo extraction have strong inhibitory effect for Chinese cabbage germination. Comprehensive of analysis the result of seed obsorb water test and scanning electron microscopy observation,we think the dormancy reason of ormosia hosiei andormosia xylocarpa mainly are seed coat permeability barriers. As for their inclusion of seed coat and seed embryo weather inhibited germination of ormosia hosiei and ormosia xylocarpa seed, we will further study.The seed activity of Ormosia hosiei and ormosia xylocarpa show significantly different with different hard degree.The germination index,TTCH content and SOD activity of hard seed are higher than those of non hard seed, and their soluble sugar content, electrical conductivity, MDA content are lower than non hard seed, so the vigor of hard seed were higher than that of non hard seed. Based on the comprehensive evaluation of membership function, the best method of broken hard seed of ormosia xylocarpa and ormosia xylocarpa are 90℃ hot water soaked treatment and acid treatment 10 min respectively.With the extension of storage time, ormosia hosiei and ormosia xylocarpa seed under different storage conditions showed deterioration at different degrees. The main performance of deterioration are germination rate decreasing,storage substance hydrolyzing and protective enzyme system damaging. Storage after nine months,the seed germination rate, starch, fat and TTCH content and SOD activity of ormosia hosiei and ormosia xylocarpa seed showed decreased,the soluble sugar content increased,and the protein content first decreased then increased. The electrical conductivity and MDA content showed increasing trend. Based on the comprehensive evaluation of membership function,Ormosia hosiei seed suit for cold storage,the best storage condition is seed water content of 14% and-15℃. The ormosia xylocarpa seed suit for ultra dry storage,the best storage condition is seed water content of 4.7% and normal temperature.