| In this study, with optimized paraffin sections, five years old Feijoa sellowiana Berg. seedling was used to study the flower bud differentiation and embryological development under natural growth conditions, and analyzed the dynamic changes of nutrient metabolism during flowering. This paper aims to understanding the corresponding relationship between the bioclimatology and the feature of growth, development and reproductive biology. In order to provide scientific and technological support for the flower development smoothly, florescence regulation, cultural management etc., meanwhile further researches on Feijoa evolving progress has vital significance. The main results are as follws:(1) The blossom of Feijoa was divided into six stages: bud germination period, bud sprouting period, budding phase, initial blooming, blossom period and end of blooming. Blossom in late April and early may in mianyang region, flowering lasts about 35 ~ 40 days. The duration of the flowering period of single plant was about 9 d. The blooming patterns of per plant was usually southeast of the plant blossom early than northern, and the duration of flowering was longer. Feijoa was bisexual flower, stamens numerous, simple postil, gorgeous flow, usually have 4 petals, Stigma higher than stamens.(2) Paraffin section was carried out on the flower buds of Feijoa, can be improved from the following aspects: the fixed material was softened, now the optimal conditions was using 20% HCL to soak materials 24 hours for softening process; in dehydrating and transparent process, materials soaking time changed into 1.5 hour; used fewer and more times added wax as soaking method, the dipping time was 3 days. This method had remarkable effects in hardened material.(3) The development of Feijoa sellowiana’s flower bud differentiation was divided into six stages: predifferentiation, early stage of differentiation, the sepal differentiation stage, petal differentiation stage, the stamen differentiation stage and the pistil differentiation stage. Flower bud differentiation began in late March in Mianyang region, and the duration was about 30 days. After the completion of bud differentiation, the growth enter bud development stage, around 5 month.(4) Contents of total sugar, total nitrogen, soluble sugar, soluble protein, nucleic acid, starch and other physiological indicators in buds and leaves during floral differentiation were determined and analyzed. The results show that in the whole process of flower bud differentiation, the contents of total sugar, starch, soluble sugar and nucleic acid in flower bud were significantly higher than that in leaf, as with total nitrogen, nitrate nitrogen and sucrose, there was a peak in the physiological transition period; the content of total nucleic acid and RNA has been increased, and the increase of RNA content was more significant; after the flower bud entered the differentiation stage, the C/N in flower bud was significantly higher than in leaf. It is indicated that these substances and C/N played an important role in the process of flower bud differentiation in Feijoa.(5) Feijoa had four ventricles in each anther, The anther wall consists of four layers: the epidermis, the endothecium, middle layers, and the secretory tapetum. After the maturation of anther, only one layer of fibrous cells was remained in the wall of pollen sac, and the rest layers disappeared. The ripened pollen was of 2-cell type. Ovary was inferior, axial placenta, bitegmic, anatropous ovule, tenuinucellate. |
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