Study on the Anatomical Structures in Development of the Nurse Seed Grafted Union of Camellia oleifera

Conventional paraffin sectioning was adopted to conduct anatomical examination of the nurse seed grafted Camellia oleifera union during development.Results showed that at day 4 after grafting,the nurse seed grafting union became the isolation layer;at day 8,the callus in the root stock was observed;at day 16,the callus was found in the scion;at day 22,the root stock connected the scion;at day 29,the nurse seed grafting union formed the vascular cambium;at day 35,vascular bundles was formed,which indicated that the nurse seed grafted seedling survived.Before induction of callus in the nurse seed grafted C.oleifera union,the primary organization structure of the stock accelerated growth and development,and gradually became similar to the structure of the scion.The cambium and other parenchyma cells in the grafted union could all be induced to produce callus,but the cambium was the principal source.