不同三叶草对二斑叶螨生长发育和繁殖的影响

【目的】明确红三叶、白三叶和杂三叶3种寄主对二斑叶螨Tetranychus urticae Koch生长发育和繁殖的影响,以及3种寄主间二斑叶螨的生物学差异。【方法】在室内(25±1)℃条件下,采用离体叶片法研究了3种三叶草对二斑叶螨种群参数的影响。【结果】3种三叶草对二斑叶螨生长发育、雌成螨寿命以及繁殖力有显著影响(P<0.05)。在杂三叶上,二斑叶螨发育历期、产卵前期明显比红三叶和白三叶上要长,而且雌成螨寿命和产卵期也明显缩短。每雌产卵量在红三叶上最高(150.87粒),白三叶次之(139.43粒),而杂三叶上最低(86.95粒)。二斑叶螨在3种三叶草上的存活曲线均为Ⅰ型,存活率高低依次为红三叶、白三叶和杂三叶。净增殖率(R0)、内禀增长率(rm)和周限增长率(λ)在红三叶上最高、杂三叶上最低,而平均世代周期(T)和种群加倍时间(Dt)在杂三叶上最长、红三叶上最短。【结论】3种三叶草对二斑叶螨的适合度具有一定差异,红三叶和白三叶对二斑叶螨具有更高的适合度。

Effects of different clover species on the development and fecundity ofTetranychus urticae Koch

Objectives] The two-spotted spider miteTetranychus urticaeKoch is one of the most economically important pests of a wide range of crops and pastoral grasses worldwide. To clarify the biological characteristics ofT. urticae, the effects of different clover species on its development and fecundity were investigated.Methods]Three treatment groups of two-spotted spider mites were fed either red clover, white clover, or alsike clover, under laboratory conditions at a constant temperature (25±1)℃. Results] The three clover species had significant effects on the developmental time, adult female longevity and fecundity (P<0.05). The developmental time and pre-oviposition period of mites fed on alsike clover were longer than in those fed on red or white clover, and adult female longevity and the duration of oviposition were markedly shorter. Mites fed on red clover laid the highest average number of eggs per female (150.87), followed by those fed on white clover (139.43), whereas those fed on alsike clover laid the lowest (86.95). The survival curves of all three treatment groups were Deevey type I. Survival was highest on red clover, followed by white clover, and lowest in mites fed on alsike clover. The net reproductive rate (R0), intrinsic rate of increase (rm) and finite rate of increase (λ) were highest on red clover and lowest on alsike clover, and mean generation time (T) and population doubling time (Dt) were longest on alsike clover and lowest on red clover. Conclusion] Clover species had a strong effect on the development and fecundity of the two-spotted spider mite which had higher fitness on red and white clover than on alsike clover.