Biological and molecular characterization of Aromia bungii (Faldermann, 1835) (Coleoptera: Cerambycidae), an emerging pest of stone fruits in Europe

Abstract

The red-necked longhorn beetle (RLB) Aromia bungii (Fald.) is an emerging pest of stone fruit trees, native to East Asia, accidentally introduced in Europe (Germany and Italy) and Japan. Threatening seriously the stone fruit crops in Europe, RLB was added to both the EPPO A1 and priority pest lists of quarantine species. Molecular analyses highlighted that all specimens recovered in southern Italy share the same haplotype, different from the German one, supporting that the invasive process in Europe started from at least two independent introductions. To fill the existing gap of biological knowledge about A. bungii, several laboratory tests were carried out on specimens collected in the outbreak area of Naples (Italy). Results suggest a high biotic potential of the RLB Italian population. Females showed a short pre-oviposition period while the period of oviposition lasted about three weeks, with a rate of 24.2 eggs/day. Each female laid an average of 587.5 eggs and spawned the largest amount of eggs during the first week after emergence. Fed males live up to 62 days at 20 °C while fed females about 63 days at 25 °C. These results are crucial to draw up a multi-facet IPM approach against A. bungii in the outbreak areas.

Figure 1

Daily distribution (mean ± SE) and cumulative percentage of eggs laid at 25 °C by A. bungii females.

Figure 2

Regression between lifetime fecundity and body length in A. bungii ovipositing females (n = 18); Lifetime fecundity = −1392.85 + 65.4061*Body length; F = 24.91; df = 1, 16; P = 0.0001.

Figure 3

Comparison between the number of hatched eggs (mean + SE) of the first and the last 100 eggs laid by A. bungii (n = 18). Bars with different letters indicate significant difference at the 5% confidence level.

Figure 4

Hatching period (days after laying) and cumulative percentage of hatched eggs of A. bungii (mean + SE) at 25 °C (first 100 laid eggs).

Figure 5

Regression between ovarioles and body length in newly emerged A. bungii females (n = 10); Ovarioles number = −57.2077 + 4.52658*Body length; F = 35.09; df = 1, 8; P = 0.0004.

Figure 6

Longevity of fed (left) and starved (right) adults (♂ and ♀) of A. bungii (mean + SE) at two different temperatures (bars with different upper and lower case letter indicate significant difference at 5% confidence level).