A facultative commitment to adult migration in the larval stage can be modified again after adult emergence in some Lepidoptera when influenced by an appropriate environmental cue during a sensitive stage. This phenomenon is termed secondary regulation of migration. The sensitive stage in adult beet webworm, Loxostege sticticalis L. (Lepidoptera: Pyralidae), was determined experimentally by starvation of presumed migrant females reared from gregarious-phase larvae (induced by crowding at 10 larvae per 650-ml jar). When presumed migrant adults were starved for 24 h on either of the first 2 d after emergence, the preoviposition period was shortened. In contrast, preoviposition periods were not significantly shortened for migrants starved on day 3 or when starvation lasted for more than 1 d after emergence. Because the preoviposition period corresponds to the migratory period in beet webworm, the results suggest that the first 2 d of adult life in the beet webworm is the sensitive stage during which presumed migrants can be switched to residents by an appropriate environmental cue. During the sensitive stage or not, starvation did not influence lifetime fecundity, oviposition period, longevity, or hatching rate of eggs laid by the starvation-stressed moths. Starvation on the first day also increased tethered flight performance and accelerated both flight muscle and ovarian development. The results suggest that a pulse of starvation in the sensitive period may inhibit the expected migration by accelerating and compressing the cycle of migratory flight muscle development and degeneration, while accelerating ovarian development, which is normally suppressed until after migration.

中文翻译：

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成年后第一天或第二天的饥饿会逆转幼虫阶段在甜菜网虫中迁移的决定（鳞翅目：Pyralidae）

当在敏感阶段受到适当环境线索的影响时，在某些鳞翅目成虫出现后，可以再次修改幼虫阶段对成虫迁移的兼性承诺。这种现象被称为迁移的二级调节。成年甜菜网虫Loxostege sticticalis L.（鳞翅目：Pyralidae）的敏感阶段是通过对由群居期幼虫饲养的假定迁移雌性（由每650毫升罐中的10只幼虫拥挤引起）的饥饿实验确定的。当假定的迁徙成虫在出苗后的前 2 d 中的任何一个都挨饿 24 小时时，产卵期缩短。相反，对于在第 3 天挨饿或在出苗后饥饿持续超过 1 天的迁徙者，产卵期没有显着缩短。由于前产卵期对应于甜菜螟的迁徙期，结果表明，甜菜螟成虫生命的前 2 天是敏感阶段，在此期间，假定的迁徙者可以通过适当的环境线索转变为居民。在敏感阶段与否，饥饿不影响饥饿胁迫飞蛾产卵的终生繁殖力、产卵期、寿命或孵化率。第一天的饥饿也提高了系留飞行的表现，加速了飞行肌肉和卵巢的发育。结果表明，敏感时期的饥饿脉冲可能通过加速和压缩迁徙飞行肌肉发育和退化的周期来抑制预期的迁徙，同时加速卵巢发育，