Data from: Ovary development and cold tolerance of the invasive pest Drosophila suzukii (Matsumura) in the central plains of Kansas, United States

Environmental challenges presented by temperature variation can be
overcome through phenotypic plasticity in small invasive ectotherms. We
tested the effect of thermal exposure to 21, 18, and 11°C throughout the
whole life cycle of individuals, thermal exposure of adults reared at 25°C
to 15 and 11°C for a 21-d period, and long (14:10 hr) and short (10:14 hr)
photoperiod on ovary size and development in Drosophila suzukii
(Matsumura) (Diptera: Drosophilidae) cultured from a recently established
population in Topeka, Kansas (United States). Examination of the response
to temperature and photoperiod variation in this central plains population
provides insight into the role of phenotypic plasticity in a climate that
is warmer than regions in North America where D. suzukii was initially
established. We found both low temperature and short photoperiod resulted
in reduced ovary size and level of development. In particular, reduced
ovary development was observed following exposure to 15°C, indicating that
ovary development in females from the central plains population is more
sensitive to lower temperature compared with populations examined from the
northern United States and southern Canada. We also provide evidence that
D. suzukii reared at 25°C are capable of short-term hardening when exposed
to −6°C following 4°C acclimation, contrary to previous reports indicating
flies reared at warm temperatures do not rapidly-cold harden. Our study
highlights the central role of phenotypic plasticity in response to
winter-like laboratory conditions and provides an important geographic
comparison to previously published assessments of ovary development and
short-term hardening survival response for D. suzukii collected in cooler
climates.

温度变化带来的环境挑战可通过小型入侵性变温动物（ectotherms）的表型可塑性（phenotypic plasticity）得以克服。本研究测试了以下因素对铃木氏果蝇（Drosophila suzukii (Matsumura)，双翅目：果蝇科）卵巢大小及发育的影响：1）全生命周期暴露于21、18及11°C；2）25°C饲养的成虫暴露于15及11°C达21天；3）长光周期（14:10小时）与短光周期（10:14小时）。该果蝇种群来自美国堪萨斯州托皮卡的新建立种群。对该中部平原种群响应温度及光周期（photoperiod）变化的研究，揭示了表型可塑性在比北美铃木氏果蝇初始定殖区域更温暖的气候中的作用。研究发现，低温和短光周期均导致卵巢大小减小及发育水平降低。尤其在暴露于15°C后观察到卵巢发育减缓，表明与美国北部和加拿大南部的种群相比，中部平原种群雌性的卵巢发育对低温更为敏感。此外，我们还提供证据表明：在25°C饲养的铃木氏果蝇经4°C适应（acclimation）后暴露于-6°C时，能够进行短期硬化；这与此前认为暖温饲养的果蝇无法快速冷硬化（rapidly-cold harden）的报告相反。本研究强调了表型可塑性在应对类冬季实验室条件中的核心作用，并为先前发表的、针对较冷气候下铃木氏果蝇卵巢发育及短期硬化存活响应的评估提供了重要的地理比较。