Studies On Reproductive Biology And Physiology Of Waterlogging Stress Of Sweet Osmanthus

This dissertation studies the reproductive biology about the flower bud differentiation, embryo developing,the pollen viability, the mechanisms of seed dormancy,the way of relieved dormancy and physiology of waterlogging stress of Sweet Osmanthus. The main results were shown as follows:1,The morphological differentiation of Sweet Osmanthus go through about half past three months,and the process is divided into seven phases. It is different on the morphological differentiation between seed cultivars and non seed ones distinctly. The developmental process of embryo and endosperm undergoes about 4.5 months.2,The pollen energy is the highest in the solid culture medium made of 10% sucrose+100mg/mL boric acid +2% agar , the pollen energy are all low obviously of different varieties.3,There is distinct difference on length, width, single seed weightiness and endocarps sculpture between different cultivar seeds.4,Though the endocarps is very thick, it don't effect water absorption. The embryo is normal. The extraction solutions of the seed capsule and endosperm all inhibit the germination of cabbage seeds and growth of cabbage seedlings. The GC-MS analysis indicates that there exist manifold organic compounds in the seed coat and endosperm, mainly fatty acids, such as oleic acid,hexadecanoic acid and Octadecadienoic acid, in addition it also has much ABA in the endosperm.In a word, the main reason of seed dormancy is stayer in the seed capsule and endosperm. the dormancy belongs to physiological dormancy.5,The contents of endogenetic ABA in the endosperm gradually descend as the time of stratification prolongs; but the contents of GA increase, the contents of ZR descend at the beginning of stratification then increase as the time prolongs, there has some repetition; the contents of IAA increase at the beginning of stratification then descend as the time prolongs. the same as the ratios of GA/ABA,IAA/ABA and ZR/ABA, as a result, the dormancy is gradually overcome.The contents of soluble sugar and soluble protein rise at the beginning of stratification then descend as the time prolongs, but the contents of starch gradually descend.6,The treatment of soaking with 1000 mg/LGA followed by stratification of wet sand (1:3) in 2-4℃refrigeratory,75days can significantly arouse the germination percentage and is effective methods to overcome dormancy of Sweet Osmanthus seeds. 7,The vase life of cultivars is different. Anti-staling agents with cane sugar can improve water and nutrition during Vasing, the vaselife was'Ziyingui'﹥'Duoya Jingui'﹥'Sijigui'. thereby anti-staling agent can prolong the enjoying time to a certainty degree.8,The changing trends of physiological characteristics under waterlogging stress is as follow : The chlorophyll content decreased gradually, the relative electric conductivity decreased at first then increased subsequently, while MAD content,the praline content,the activities of POD and SOD increased firstly and then decreased.The ability of anti-waterlogging is'Zhusha Dangui'﹥'Tianxiangtaige'.