| The paper is mainly concerned with two parts in morphological observation and tissue culture of Eelgrass (Zostera marina L.). The results are as follows:1. The microstructure of the plant showed that the cell wall exposing to seawater in epidermal cells of leaves was highly thickened, but the other sides were normal. It was also highly thickened in the side exposing to seawater in the epidermal cells of roots and stems. This structure may function as a barrier against toxic ions to enter the epidermal cells. Chloroplasts were found mainly in the epidermal cells, indicating that epidermal cells were main site where photosynthesis occurred. Aerenchyma was found everywhere in the plant which showed the ability of adaptation to submerged life. Anatomical observation of the inflorescence showed that eelgrass was a monoecious plant, the male flower and carpel were alternating arrangement on the inflorescence. SEM photographs of the stamen and the carpel indicated that the carpel had two stigmas, the pollens of the eelgrass were filamentous. All of the above observation showed that eelgrass is able to adapt to submerged life.2. The results on experiments of tissue culture are as follows:(1) The explants were dipped in 75% Alcohol for 10 seconds firstly, then they were dipped in 1% NaClO 10 minutes, this was the best way of sterilization than other treatments.(2) MS was chosen as basic medium in the experiment in which it was better for inducing callus than 1/2 MS and PES.(3) Different concentrations of 2,4-D, IAA, 6-BA, KT and Zeatin were studied in the course of callus induction. The results demonstrated the best treatment of hormones was combination of 2,4-D 2mg·L-1 and 6-BA 1mg·L-1.(4) The best explant for callus induction was stem.(5) The experiment on inhibition of brownness for inducing callus in stems showed that the browned degree was eased up by adding active carbon to media or reducing light intensity.
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