| In Mutang sea area, Danzhou, Hainan province, utilized a method that out of settlement substratum after the first fixation to cultivate three species of the single-seed oysters. The species of these oysters: hybridism triploid oyster from the tetraploid Crassostrea gigas♀and diploid C.angulata♂development, diploid C.gigas and triploid C.gigas. We Compared the growth of three species of oysters in different culure environments, the pond and the ditch, we also compared the growth of the diploid C.angulata in different culture areas and different culture densities in the same culturing model. In addition, the waters of Wuzhizhou island, Sanya city, Hainan province, the author researched breeding technologies, the growth regulations and the ontogenetic processes of the larvae of Pinctada maxima and Pteria penguin.1. The result suggest that, the shell height and length of the oysters cultured in the pond were significantly larger than it cultured in the ditch(p<0.05), but it had no significant difference between the shell width and weight (p>0.05). By observing different breeding density gradient groups, we found that the shell height, shell length, shell width and weight of the higher density group is smaller than the lower groups. Looking on the growth rate, there were no significant difference between the groups of20large shells per cage and40per cage(p>0.05). The groups of20small shells per cage grew significantly faster than the groups of40small shells per cage (p<0.05). The40small shells per cage groups and60small shells per cage had no significant difference (p>0.05). The death rates of different density gradient groups had no significant difference (p>0.05). The death rate had a great relationship with the environment, the pond groups death rates were higher than the water ditch groups.2. Although three different genetic structure oysters(No.1was hybridism triploid oyster, No.2was diploid C.gigas and No.3was triploid C.gigas.) didn’t show a large growth difference in pond. The groups cultured in the ditch, the Group D1was significantly larger than Group D2and D3both in the length (shell height, shell length, shell width) and weight (p<0.05). We could draw the conclusion that the Group Dl was more adaptable the environment of the ditch than the Group D2and D3.3. After6moths breeding, shell height, shell length, shell width and weight of all of the ditch-groups are higher than the pond-groups. The result suggest that, the shell height, shell length, shell width and weight of triploid hybrid oysters cultured in the pond were significantly larger than it cultured in the pond(p<0.05). The other two kinds of oysters were no significant difference even in different breeding environments. Through the whole experiment, we could draw the conclusion that different culture sites, the mortality rates had significant difference in three kinds of oysters(p<0.01), the death rates of pond groups were larger than the ditch groups.4. We researched the key point in the breeding process of the pearl oysters, Pinctada maxima and Pleria penguin, including the key techniques of the artificial insemination, the bait cultivatology, the incubation and breeding, as well as the seed-adhering. After the insemination, by a microscope, we observed and photographed the development of P.maxima and P.penguin pearl oyster larvae starting from the fertilized egg and researched the morphological changes of the two kinds of pearl oyster larval stage.5. The change in the growth rates of the P.maxima and P.penguin larvae could be divided into four stages:the period from the D-shaped larval stage to the prime umbo stage, the larval grew most slowly. From the umbo stage to the early metamorphosis stage, the larvae grew faster. From the early metamorphosis stage to settlement grew slower. After the settlement, these larvae entered the fastest growth stage. |
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