马氏珠母贝养殖群体的生长特性研究

Growth characteristics of cultured population of Pinctada martensii Dunker

从养殖于深圳大亚湾海区的3月龄马氏珠母贝Pinctada martensii养殖群体中挑出较大和较小个体的贝分为2个组,分别命名为大个体组和小个体组,以同样的方式进行养殖,在3—12月龄间每隔1—2月对其生长进行测量;同时取12月龄的贝200个编号进行个体生长测量,到16月龄结束。经t检验,大个体组贝在各个测量阶段4个性状(壳长、高、宽和体重)都显著大于小个体组(p<0.01),大个体组日增长幅度在3—9月龄也大于小个体组;经最小显著差法分析,个体测量的3个亚组间大小存在显著差异(p<0.01),顺序为Ⅰ(Ⅰ’)<Ⅱ(Ⅱ’)<Ⅲ(Ⅲ’),但其日增长量为Ⅰ(Ⅰ’)>Ⅱ(Ⅱ’)>Ⅲ(Ⅲ’),同时显示出初始值较大的个体在后期仍有较大的增长趋势,但个别初始值较小的个体增长快,在生长后期个体也很大。3—9月龄贝的大小平均增长率大于11—16月龄贝,而体重增长要小于11—16月龄贝。该研究结果对选择育种中亲本的选留、珍珠生产中植核贝的选留具有较大的指导作用。

To study the growth characteristics of pearl oysters of different sizes in one population of Pinctada rnartensii Dunker, the bigger and smaller oysters at the age of 3 months were selected from a cultured population at the Daya Bay, and named respectively as big and small groups （B and S groups）. At intervals of 1--2 months, four growth traits of the two groups were measured at the age of 3--11 months, and compared by t-test analysis. 200 oysters at the age of 12 months were numbered and messured at intervals of 2 months until they were 16 months old. The results showed that the B group was significantly lar-ger than the S group for all four traits （p〈0.01） at every measurement stage, and the daily growth of B group was also greater than that of the S group at the age of 3--9 months. The analysis of LSD indicated that the four traits were significantly different （p〈0.01） among the three subgroups at each measurement stage, in t.he order of Ⅲ （Ⅲ＇）, Ⅱ （Ⅱ＇）, and Ⅰ （Ⅰ ＇） from high to low, whereas the daily growth was in the order of Ⅰ （Ⅰ ＇）, Ⅱ （Ⅱ＇）, and Ⅲ （Ⅲ＇） from high to low. It also showed that the oysters with initially bigger size would also have bigger size at the later growth stages, hut some oysters with initially smaller size could become bigger at the later stages. The oysters at the age of 3--9 months grew faster than those at the age of 11--16 months in shell size, hut slower in weight. The results will he very helpful for parent selection in selective breeding and selection of host pearl oysters in pearl culture.