Predicting white peach scale phenology on kiwifruit in Sichuan

White peach scale (<i>Pseudaulacaspis pentagona</i>) is a polyphagous pest of perennial horticulture in Asia and many other warm-temperate and tropical regions. In China, it is a serious pest of kiwifruit. The optimal time to control <i>P. pentagona</i> field populations is at the first instar stage of the first, spring generation. Three methods for predicting the hatching of eggs of the first generation from field populations were tested on kiwifruit in Sichuan, based upon the accumulation of heat units (day-degrees) above a developmental threshold, calculated as 10.75 °C. A method developed for <i>P. pentagona</i> control in tea in Japan gave excellent predictions of 50% hatching in 5 of the 6 years under study (2009–2014). The other two methods also gave acceptable predictions of dates of 50% egg hatching (within 5 days of field observed dates). These models may be used as a basis for forecasting spring insecticide application dates targeting the first instar stage (crawlers and settled ‘white caps’).桃白蚧（*Pseudaulacaspis pentagona*）是一种多食性害虫，可危害亚洲及诸多其他暖温带、热带区域的多年生园艺作物。在中国，它是猕猴桃的重大农业害虫。防治田间桃白蚧种群的最佳时期为春季第一代的1龄若虫阶段。本研究以10.75℃作为发育阈值温度，基于该阈值以上的热单位（日度，day-degrees）累积量，在四川猕猴桃种植园中开展试验，对3种预测田间种群第一代卵孵化情况的方法进行了验证。此前日本为防治茶园桃白蚧开发的一种预测模型，在本次研究的6年（2009-2014年）中，有5年均可精准预测50%卵的孵化时间。另外两种方法同样可给出可接受的50%卵孵化期预测结果，预测时间与田间观测日期的误差均在5天以内。上述模型可作为以1龄若虫阶段（移动若虫与固定后的“白色蜡盖”）为防治靶标的春季杀虫剂施用时间预测的依据。