两种体色日本蟳卵巢发育及配偶选择的研究

Ovarian development and mating choice in Asian swimming crab Charybdis japonica

为探讨日本蟳Charybdis japonica体色与繁殖的关系,于2009年3月—2010年1月在大连市黑石礁海域连续采样,比较了体色青绿的花盖和体色暗红的赤甲红两种蟹的性腺指数和肝胰腺指数,在选择交配试验中,研究了正常体色蟹及人工染色蟹的配偶选择。结果表明:花盖和赤甲红的性腺指数均在5—6月间明显升高,其中赤甲红涨幅明显,6月时达最大值6.64%,而花盖为5.22%,但两者无显著性差异(P>0.05);赤甲红、花盖的性腺指数与其肝胰腺指数均呈负相关,但后者达到显著性水平(P<0.05);赤甲红和花盖雌蟹多与雄性赤甲红交配,交配率分别为80.0%和66.7%,显著高于与雄性花盖的交配率(P<0.05);相近的15组试验蟹中,人工染成红色的花盖雄蟹和未染色雄蟹与花盖雌蟹的交配率分别为40%、60%,但二者无显著性差异(P>0.05)。研究表明,体色并不是日本蟳选择配偶的决定因素。

The gonado-somatic index（ GSI） and hepato-somatic index（ HSI） were monthly measured in Asian swimming crab Charybdis japonica with two body colors,red one named Chijiahong and gray-green one named Huagai,collected from Heishijiao coast in Dalian from March 2009 to January 2010 to study the relationship between body color and reproduction. Then,a selective mating experiment was designed using two different color crabs and artificially stained red crab. Results showed that an increase in GSI was observed in both different color crabs from May to June,especially in the red Chijiahong,with the maximal GSI of 6. 64% in the red Chijiahong and 5. 22% in the Huagaiin June,without significant differences in GSI at May and June between Chijiahong and Huagai（ P〉0. 05）. The relationship of GSI and HSI was negative for both color morphs in the monthly sampling,with significant level for Huagai（ P〈0. 05）. Male Chijiahong had more opportunities to mate with both female Chijiahong（ mating rate of 80. 6%） and Huagai（ mating rate of 66. 7%）,without significant difference in mating rate among female Huagai with artificially stained red male（ 40%） and normal male Huagai（ 60%）（ P〈0. 05）,indicating body color has not significant role in mate choice of Asian swimming crab.