Morphological, Cytological And Molecular Biological Classification Of Alnus Mill.and Osmanthus Fragrans (Thunb.) Lour.

1. Studies on cultivar's classification of Osmanthus fragrans breeds Sichuan ProvinceMore than 140 standard plants of Osmanthus fragrans were selected as standard plant based on morphological differences after investigating the main cultivation area of Osmanthus fragrans in Sichuan Province.After comprehensive analysis on all these morphological characters, following results were reached:(1) Totally 59 Osmanthus fragrans cultivars were recorded, including 6 in Fragrans Group, 16 in Latifolius Group, 24 in Thunbergii Group and 13 in Aurantiacus Group.(2) Keys to all the cultivars of each group were given.(3) The morphological characters of the fruit and seed of Osmanthus fragrans is very stable, which could be used for cultivar classification apart from flower characters.(4)Based on comprehensive comparison, 4 cultivars, which having high ornamental value were recommended, including 'Zaohuazijingui', 'Liuyejingui', 'Luanyejingui', 'Yichuanhong'.(5) ISSA was utilized to classify 59 cultivars, with the results consistent with the traditional classification system.2. Study on the pollen morphology of Osmanthus fragrans cultivars in SichuanPollen morphology of 46 cultivars in Osmanthus fragrans is examined with SEM. The result indicated that:(1) There were common character in pollen polarity, pollen shape and style of sexine sculpture, namely the pollen grain were heteropolar; 3-labed rounded in AMB; N3P4C5 according to the NPC system classification; with reticulate ornamentation; All pollen approaches spheroidal. This indicated that the Osmanthus fragrans cultivars were natural group with close relationship, which supported the homogeneity of Osmanthus fragrans as one species.(2) There were certain differences in some pollen morphological aspect such as sizes, sexine ornamentation, germinators, which displayed rich heredity multiplicity existed among Osmanthus fragrans cultivars.(3) Pollen of some cultivars contained two either three kind of sexine ornamentation or the shape, this revealed that the evolution of O. fragrans cultivars might not be a single linear relations.(4) There were obvious difference of pollen morphology between vivid pollen and dry pollen.