Predicting white peach scale phenology on kiwifruit in Sichuan

Figures & data

Table 1. Data used to calculate the development rate–constant temperature relationship for P. pentagona egg hatching.

Temperature (°C)	Number of insects	Days to 50% hatch	Number of insects	Days to 50% hatch	Number of insects	Days to 50% hatch	Number of insects	Days to 50% hatch	Mean
29	760	5.5	714	6	457	5.5	–	–	5.67
26	734	6	957	6.5	516	6.5	945	7	6.5
25	424	7	504	7.5	428	7	–	–	7.17
23	552	7	471	7.5	662	8	592	8.5	7.75
20	450	11	485	11	706	12	508	11	11.25
17	470	17	564	15.5	514	16	540	17	16.375

Figure 1. The relationship between cumulative % emergence of first generation Pseudaulacaspis pentagona crawlers on Actinidia chinensis ‘Hongyang’ canes and heat unit accumulations at four constant temperatures over 2 years.

Table 2. Empirical model outputs.

Percentile crawler emergence (%)	Start date	Base temperature (°C)	DD to event	RMSE
10	20 February	3	603	8.19
50	17 February	4	584	19.97
75	18 February	5	552	13.16
90	25 February	0	876	17.17

DD, day-degrees to event (% crawler emergence); RMSE, root mean square error of predicted minus observed event (% emergence) for the 4 years’ data used for model development.

The start date and base temperature for day-degree accumulations for predicting 10%, 50%, 75% and 90% Pseudaulacaspis pentagona first generation crawler emergence on Actinidia chinensis ‘Hongyang’. Results are based on field data collected from 2009 to 2012 in Sichuan.

Figure 2. Emergence curves for first generation Pseudaulacaspis pentagona crawlers on Actinidia chinensis ‘Hongyang’ at Shifang, Sichuan (●), and predictions from three models: (1) Takeda (2004) (▪); (2) biofix (▴); and (3) data mining (○) for 6 years (data mining for 2 years only).

Table 3. Date of 50% crawler emergence of the first (spring) generation of Pseudaulacaspis pentagona on Actinidia chinensis ‘Hongyang’ and results of three model predictions for 50% crawler emergence in the field for 6 years at Shifang, Sichuan, China.

Year	Actual date	Takeda (2004)	Biofix	Empirical
2009	110	110	110	–
2010	115	125	122	–
2011	115	117	117	–
2012	118	120	120	–
2013	98	99	106	101
2014	113	114	118	111

Data are days from 1 January.

Takeda M. 2004. Effects of temperature on oviposition in overwintering females and hatch in first-generation larvae of Pseudaulacaspis pentagona (Hemiptera: Diaspididae). Appl Entomol Zool. 39:15–26. doi: 10.1303/aez.2004.15

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