Lethal temperature for pinewood nematode, Bursaphelenchus xylophilus, in infested wood using radio frequency (RF) energy

Journal of Wood Science

Official Journal of the Japan Wood Research Society

Table 2 Nematode survival at target temperatures of 56 °C and above related to probe measurements after a 1 min hold time relative to IR temperature readings

Sample ID	Minimum temp. probe reading	Maximum temp. probe reading	Average temp. probe reading	Minimum temp. reading from IR images	Total no. of live nematodes
56-10	67	92.4	79.7	50.2	333
56-2	61.2	84.8	73.0	53.3	88
56-4	65.2	91.6	78.4	50.1	29
56-5	52.6	74.1	63.4	36.1	2,554
58-4	58.1	62.8	60.5	40.3	318
58-6	59.6	97.3	78.5	41.9	112
60-2	51.7	61.3	56.5	47.7	122
60-3^a	90.7	100.8	95.8	67.6	2
63-1	78.9	84.8	81.9	49.6	20
63-2	74.9	84.6	79.8	50.1	100
63-5	54.5	70.8	62.7	47.1	528
65-4	65.3	85	75.2	Missing	4
70-2	79.4	98.4	88.9	49.1	39

The IR images of the same samples indicated that all samples (except sample 60-3) had cold spots detected by IR (e.g., temperatures lower than 56 °C)
^aThis row is an anomaly as none of the temperatures shown were below 56 °C. The temperature probes only measure a small area of the block and temperatures can vary as much as 20 °C between areas as little as 10 mm apart. The IR images usually resolve any cold spots undetected by the temperature probes, but in this case, it is possible that the cold spot was on the back of the test block which was not captured by the IR camera