Camellia grijsii Hamce is used as a woody edible oil tree and wellknow for its commercial value in Southern China. The plants rarely set viable seeds and have little work on the reproduction biology. In order to verify whether there was any obstacle of male reproduction in the C. grijsii, microsporgenesis and male gametogenesis in C. grijsii have been evaluated by paraffin section technique. The results are showed that the development of the anther wall belonged to a basic type and consisted of epidermis, endothecium, middle layers and tapetum. The tapetum conformed to the glandular type. Cytokinesis during meiosis of the microspore mother cell was simultaneous type. A majority of the microspores were arranged in tetrahedral tetrads. The mature pollen grains were 2-cell type and had three germ pores. Anthers were dehiscent and pollen grains shed on the early-February. Based our results, we did not find the abnormal male flower in the C. grijsii, suggesting that male gametes were fertile and male sterility was not the major cause of the low seed set in the C. grijsii.

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Ziziphus jujuba Mill. is one of the most important fruit crops and has been cultivated in China for more than 4000 years. Z. jujuba fruit is rich in nutritional and medicinal values. Compared to other wood fruits, Z. jujuba is unique in its flowering and fruiting characteristics. Floral buds differentiation and formation of Z. jujuba is an essential process that affects yield. Z. jujuba 'Jinsi No.4' blooms profusely, yet its final yield is low. In this study, the floral bud differentiation and development of 'Jinsi No.4' were examined by paraffin section. Results showed that the floral buds of 'Jinsi No.4' differentiated in the current year and started from early April. The duration of a single flower differentiation was short, taking only 7 days for maturation of flowers buds. Floral bud differentiation of 'Jinsi No.4' can be divided into six stages, i.e., pre-differentiation, initial differentiation, sepal differentiation, petal differentiation, stamen differentiation, and pistil differentiation. Flower development experienced seven stages, i.e., alabastrum, alabastrum break, sepal flattening, petal flattening, stamen flattening, filament withering, and ovule swelling. Dysplasia was observed in some floral organs in Z. jujuba 'Jinsi No.4', suggesting that the dysplasia of floral organs may be one of the main reasons for low yields. Our findings on flower bud development in 'Jinsi No.4' will contribute to its production and flowering management in Hunan area of southern China.

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