【摘要】 设置300、450、600、750和900只/667m~2,5个密度梯度每个梯度3次重复,选用23.1±0.8 g/只的雌蟹和20.8±0.7 g/只的雄蟹按照1∶1投放稻田,研究不同放养密度对养殖效益的影响。结果表明:随着扣蟹投放密度增加,成蟹回捕率呈下降趋势,成蟹单产水平呈上升趋势,成蟹规格呈下降趋势,水稻单产呈现先增长后下降趋势。扣蟹投放密度与成蟹回捕率呈线性负相关,相关系数为-0.836,回捕率之间差异显著(P <0.05),回归方程为Y=-0.000 2X+0.785 2(R~2=0.675,P <0.01);扣蟹投放密度与单产水平呈线性正相关,相关系数为0.978,单产水平差异极显著(P <0.01),回归方程为Y=-0.035 4X+10.18(R~2=0.953,P <0.01);扣蟹投放密度与成蟹规格呈负线性相关,相关系数雄蟹为-0.792,雌蟹为-0.800,雄蟹和雌蟹规格差异均极显著(P<0.01),回归方程雄蟹为Y=-0.029X+114.6(R~2=0.598,P <0.01),雌蟹为Y=-0.017X+84.62(R~2=0.613,P <0.01);扣蟹投放密度与水稻单产回归方程为Y=-0.000 6X2+0.822 7X+286.84(R~2=0.871,P <0.01)。根据试验结果,盘锦地区稻田成蟹养殖中规格为20～25 g/只的扣蟹最佳的投放密度是450只/667m2左右。更多还原

【Abstract】 The effects of different stocking densities on the results of farming were studied with 23.1±0.8 g/each female and 20.8±0.7 g/each male crabs in paddy fields at a ratio of 1 ∶ 1, 4 500, 6 750, 9 000, 11 250 and 13 500 crabs/hm~2 were set up in the experiment, and three repetitions for each gradient. The results showed that with the increase of crab density, the recapture rate of adult crabs showed a downward trend, the yield level of adult crab showed an upward trend, the size of adult crab showed a downward trend, and the yield of rice showed a downward trend after the first increase. There was a linear negative correlation between the stocking density and the recapture rate of adult crabs, and the correlation coefficient was-0.836. There was a significant difference between the recapture rates(P < 0.05), the regression equation was Y=-0.000 2 X+0.785 2(R2=0.675, P<0.01). The density of larval crab was positively correlated with the yield level, the correlation coefficient was 0.978, and the yield level was significantly different(P< 0.01), the regression equation was Y=-0.035 4 X+10.18(R~2=0.953, P<0.01). There was a negative linear correlation between the size of adult crabs and the density of larval crabs. The correlation coefficient was-0.792 for males and-0.800 for females. There were significant differences between size of male and female crabs(P<0.01). The regression equation was Y=-0.029 X+114.6 for males(R~2=0.598, P<0.01) and Y=-0.017 X+84.62 for females(R~2=0.613, P<0.01). The regression equation between crab density and rice yield was Y=-0.000 6 X2+0.822 7 X+286.84(R~2=0.871, P<0.01). According to the comprehensive test results, the adult crab market in Panjin area and the breeding technology level, the optimum throwing density of crabs with the specifications of 20 to 25 g per crab is about 6 750 crabs/hm~2.Key words更多还原