To clarify the effect of ambient temperature on the abundance of the two pecky rice bug species Niphe elongata and Cletus punctiger in organic rice paddy fields, we studied the relationships between the abundance of these species and temperatures recorded from November to April in Yamaguchi Prefecture, Japan, in 2022 and 2023. The periods during which temperature affected the abundance of both species were determined. Our analyses revealed that the abundance of N. elongata was significantly and positively related to the average minimum temperature in mid-April, suggesting that the low temperatures after the diapause termination may be associated with N. elongata mortality. The abundance of C. punctiger was significantly and positively related to the average maximum temperature in mid-March, suggesting that the higher temperature soon after the diapause termination makes it possible for overwintered C. punctiger adults to feed on host plants from earlier in the season. The heading period of rice was also observed to affect both species’ abundance in paddy fields. These results may allow us to estimate the abundance of both species based on the temperature before the start of rice cultivation and the rice heading period.
Sumita et al. (Thu,) studied this question.