Effects of temperature on the developmental biology of Thaumatotibia batrachopa

The macadamia nut borer, Thaumatotibia batrachopa, is one of the major pests of macadamia in South Africa. However, there is a lack of information on the effects of temperature on the developmental biology of this pest. We compared the effects of different constant temperatures on the pre-oviposition period, fecundity, mated adults' longevity, and development duration of the life stages. In addition, we determined the models that best illustrate temperature-dependent development rate and estimated thermal requirements. There was a significant variation between temperatures in all tested parameters. The pre-oviposition period, longevity, and development duration significantly increased with decreased temperature. The fecundity was highest at lower temperatures and lowest at higher temperatures. The T. batrachopa required 564.72 degree days to develop from egg to adult, with a Tmin of 10 degrees Celsius, Topt of 30 degrees Celsius, and Tmax of 36 degrees Celsius. Our findings align with the general trend of development duration, which increases with decreased temperatures. The degree days from our study will provide an accurate prediction of T. batrachopa phenology based on field temperatures and have various implications for managing this pest.

澳洲坚果蛀螟（Thaumatotibia batrachopa）是南非澳洲坚果种植中的主要害虫之一。然而，目前针对该害虫发育生物学受温度影响的相关研究仍较为匮乏。本研究对比了不同恒温条件对该虫产卵前期、繁殖力、交配成虫寿命及各虫态发育历期的影响；此外，本研究还筛选出最能表征其温度依赖型发育速率的模型，并估算了其热需求参数。所有被测参数在不同温度间均存在显著差异：产卵前期、成虫寿命及各虫态发育历期均随温度降低而显著延长，其繁殖力在较低温度下达到峰值，在较高温度下降至最低水平。该虫从卵发育至成虫共需564.72日度，其发育起点温度（Tmin）为10℃，最适发育温度（Topt）为30℃，最高发育温度（Tmax）为36℃。本研究结果与“发育历期随温度降低而延长”的通用规律相符。本研究获得的积温数据可基于田间温度精准预测澳洲坚果蛀螟的发生物候，对该害虫的防控管理具有多方面的实践价值。