种群密度和培养体积对发头裸腹溞生长和繁殖的影响

研究了不同培养密度(D1=100 ind·L-1,D2=150 ind·L-1,D3 =300 ind·L-1)和培养体积(V1 =50 mL,V2=100 mL,V3 =400 mL)对发头裸腹溞生长和生殖的影响.结果表明:在相同培养密度下,发头裸腹溞首次怀卵体长、雌体第一窝幼溞数和后代总数均随着培养体积的增大而减少,而雌体所产后代的性比(雄体∶雌体)随着培养体积的增大而增大.在相同培养体积下,雌体产出后代总数随着培养密度的增加而减少.雌体最大首次怀卵体长(0.95±0.10 mm)和最大后代总数(171.3±19.8 ind)均出现在D1V1组合,最大性比(0.54±0.05)出现在D3V2组合.培养密度和培养体积及其协同作用对发头裸腹溞雌体后代总数、后代性比均具有显著影响(P＜0.001).

Effects of population density and culture volume on the growth and reproduction of Moina irrasa

A laboratory experiment was conducted to study the effects of different population density(D1:100 ind·L-1,D2:150 ind· L-1,D3:300 ind·L-1) and culture volume(V1:50 mL,V2:100 mL,V3:400 mL) on the growth and reproduction of Moina irrasa at 25 ℃.At the same culture density,the body length of the M.irrasa females at their first pregnancy,the first brood,and the total offsprings per female decreased with the increase of culture volumes,while the sex ratio(male/female) of the offsprings was in adverse.At the same culture volumes,the total offsprings per female decreased with the increase of culture density.At D1V1,the body length of the females at their first pregnancy(0.95±0.10 mm) and the total offsprings(171.3±19.8 ind) per female were the maximum.At D3V2,the sex ratio was the maximum(0.54±0.05).Culture density,culture volume,and their interactions significantly affected the total offsprings per female and the sex ratio(P<0.001).