PROGENY AND SEX ALLOCATION DECISIONS OF THE POLYEMBRYONIC WASP COPIDOSOMA-FLORIDANUM
PROGENY AND SEX ALLOCATION DECISIONS OF THE POLYEMBRYONIC WASP COPIDOSOMA-FLORIDANUM
复制标题
DOI：
10.2307/5756
复制
发表时间：
1995-03-01
影响因子：
4.8
通讯作者：
STRAND, MR
中科院分区：
文献类型：
--
作者：
ODE, PJ;STRAND, MR
1. 通过一系列的室内实验和野外采集的观察资料，研究了多胚蜂蜂（Copinosoma floridanum）的生殖生物学。雌虫每寄主产一到两个卵，产生全雄、全雌或两性（混合）的窝。每一颗卵产生多个胚胎，这些胚胎要么发育为从未长成成虫的早熟幼虫，要么发育为具有生殖能力的成虫。发现寄主卵被寄生时的年龄对后代的卵卵数量和性别比有实质性影响。(1)随寄主卵龄的增加，雌卵和混合卵的卵数和总体存活率降低，而雄卵的卵数和存活率相对不受寄主卵龄的影响。（ii）寄主卵年龄较大时，混合卵的后代性别比（雄性比例）较高。（iii）雌雄体大小与窝仔数呈负相关。体型较大的雌性繁殖能力较强，体型较大的雄性交配能力较强。寄主卵年龄也影响了雄性和雌性之间的竞争不对称。在年轻的寄主卵中，雌性早熟幼虫比雄性丰富得多，并且有助于减少混合卵中的雄性数量。在年龄较大的寄主卵中，雄性和雌性早熟幼虫的数量要低得多，并且大致相等。结果，在较老的寄主卵中，混合卵的性别比例更接近于相等。产卵雌性在做出产卵决定时对宿主-卵年龄和宿主相遇率作出反应。雌性在年轻的宿主中产下更多的雌性卵，而在年长的宿主中产下更多的混合卵。当相遇率低时，雌性会产下更多的混合后代，而当相遇率高时，雌性会产下更多的混合后代。
1. The reproductive biology of the polyembryonic encyrtid wasp Copinosoma floridanum was examined in a series of laboratory experiments and related to observations from field collections. Females laid one or two eggs per host, producing broods comprised of all males, all females, or both sexes (mixed). Each egg produced multiple embryos that developed into either precocious larvae that never became adult or reproductive larvae that developed into reproductive adults.2. The age of the host-egg when it was parasitized was found to have a substantial effect on offspring clutch sizes and sex ratios. (i) The clutch sizes and overall survivorship of female and mixed broods decreased with increasing host-egg age, whereas male clutch sizes and survivorship were relatively unaffected by host-egg age. (ii) Offspring sex ratios (proportion males) of mixed broods were higher in older host-eggs. (iii) Body sizes of males and females were negatively correlated with clutch size. Larger females had higher fecundities and larger males had greater mating abilities.3. Host-egg age also affected competitive asymmetries between males and females. In young host-eggs, female precocious larvae were much more abundant than males and were instrumental in reducing the number of males in mixed broods. In older host-eggs, the numbers of male and female precocious larvae were much lower, and were approximately equal. As a result, sex ratios of mixed broods in older host eggs were closer to equality.4. Ovipositing females responded to host-egg age and host encounter rates when making oviposition decisions. Females laid more female eggs in younger hosts and more mixed broods in older hosts. Females laid more mixed broods when encounter rates were low and more female broods when encounter rates were high.