Pervez Ahmad, Richmond Aaron S
Ladybird Research Laboratory, Department of Zoology, University of Lucknow, Lucknow 226007, India.
J Insect Sci. 2004;4:22. doi: 10.1093/jis/4.1.22.
The influence of age on reproductive performance of an aphidophagous ladybird beetle, Propylea dissecta was examined using male and female beetles of varying ages (1-30 days) after a single mating stimulus. All the intermediate (10 to 20 days old) and old (30 days old) age females mated with all intermediate and old age males, while only a fraction (0.29%) of younger females, 1 to 5 days old, mated with males of similar or older age. The willingness to mate was male age dependent. It increased sigmoidally with increase in adult age. Adult males were more willing to mate with females irrespective of age. Mating duration was longest amongst older adults (30 day-old males and 20 day-old females). Male age did not contribute to shaping the fecundity of the female ladybird. Fecundity was female age dependent and it increased with age up to 20 days and thereafter decreased. 20 day-old females were most fecund producing 867 eggs after a single mating. Progeny production was male age dependent and eggs sired by 20-30 day-old males had significantly higher viability than those sired by younger males. Prolonged mating increased fecundity and egg viability. The results reveal that males of intermediate age were better mates. This information may improve our understanding of the effect of aging on reproduction in ladybirds and may help mass-multiplication of the ladybird beetles using adults of optimal age.
在单次交配刺激后，使用不同年龄（1至30天）的雌雄异色瓢虫（Propylea dissecta），研究了年龄对其生殖性能的影响。所有处于中间年龄段（10至20天龄）和老龄（30天龄）的雌性都与所有中间年龄段和老龄的雄性交配，而只有一小部分（0.29%）1至5天龄的年轻雌性与年龄相仿或更大的雄性交配。交配意愿取决于雄性年龄。它随着成虫年龄的增加呈S形增加。成年雄性更愿意与任何年龄的雌性交配。老龄成虫（30天龄雄性和20天龄雌性）的交配持续时间最长。雄性年龄对雌性瓢虫的繁殖力没有影响。繁殖力取决于雌性年龄，在20天龄之前随年龄增加，之后下降。20天龄的雌性繁殖力最强，单次交配后可产867枚卵。后代产量取决于雄性年龄，20至30天龄雄性所授精的卵的活力显著高于年轻雄性所授精的卵。延长交配时间可提高繁殖力和卵的活力。结果表明，中间年龄段的雄性是更好的配偶。这些信息可能会增进我们对衰老对瓢虫繁殖影响的理解，并可能有助于利用最佳年龄的成虫大量繁殖瓢虫。
