Preliminary Study on Acoustic Characteristics of Ips grandicollis Larvae

[Objectives]The paper was to analyze the acoustic characteristics of Ips grandicollis larvae by pest acoustic detection technology,and to provide some reference for quarantine identification of pest larvae at ports.[Methods]The trial was performed in a self-invented insect sound recording container with good sound insulation effect.I.grandicollis larvae were placed separately on split P.ponderosa logs to observe and record the activities of larvae.AED-2010 was used for signal acquisition and SP-1 probe was used to collect signals at a distance of 5 cm from the larvae.The activity signals of larvae were intercepted,and the signal de-noising was further processed by Goldwave software.Finally,the acoustic signals were carried out correlation analysis by using MATLAB toolbox.[Results]I.grandicollis larvae had more regular feeding acoustic signal characteristics than crawling acoustic signal characteristics,and the two types of acoustic signal characteristics were quite different.The duration of feeding acoustic signal pulse of I.grandicollis larvae was 50-85 ms,the frequency was less than 1 KHz,and the signal frequency was mainly distributed in the range of 510.00-620.20 Hz.There was no obvious law in time domain features of larval crawling acoustic signals and the signal frequency was low,which was below 0.6 KHz and was mainly distributed in the range of 258.00-530.00 Hz.[Conclusions]It is feasible to carry out quarantine identification of I.grandicollis larvae by using feeding acoustic signals.It is suggested to select the feeding acoustic signals with obvious characteristics in the sound monitoring and identification of pests.

Object use in insects

Insects are the most diverse group of organisms in the animal kingdom,and some species exhibit complex social behaviors.Although research on insect object use is still in its early stages,insects have already been shown to display rich object-use behaviors.This review focuses on patterns and behavioral flexibility in insect object-use behavior,and the role of cultural evolution in the development of object-use behaviors.Object use in insects is not widespread but has been documented in a diverse set of taxa.Some insects can use objects flexibly and display various object-use patterns.Like mammals and birds,insects use objects in diverse activities,including foraging,predator defense,courtship,and play.Intelligence,pre-existing manipulative behaviors,and anatomical structure affect innovations in object use.In addition,learning and imitation are the main mechanisms underlying the spread of object-use behaviors within populations.Given that insects are one of the major animal groups engaging in object use,studies of insect object use could provide general insights into object use in the animal kingdom.

Genome-wide characterization of microsatellites and development of polymorphic markers shared between two weevils of Eucryptorrhynchus(Coleoptera:Curculionidae)

The weevils Eucryptorrhynchus brandti(Harold)and E.scrobiculatus(Motschulsky)are two pests of the tree of heaven,Ailanthus altissima.They usually co-occur on their host tree.However,these two species have a niche separation with different eggs-laying locations and larvae-feeding parts on the tree.Here,we characterized the distribution of microsatellites in the genome and developed genome-wide microsatellite markers shared between these two weevils.A total of 12,524 and 11,030 potential microsatellites were identified for E.brandti and E.scrobiculatus,respectively.Microsatellites with AT,TA,AC,TG,CA repeat motifs were most common for both species.We designed primers universal for two weevils and developed 14 loci with high amplification efficacy and polymorphism.We validated these microsatellite markers in three populations of each species.In E.brandti,the observed and expected heterozygosity for the genotyped loci ranged from 0.17-0.24 and 0.44-0.54;in E.scrobiculatus,the above values ranged from 0.06-0.18 and 0.18-0.27.Based on the developed microsatellite markers,we found that populations of both weevils have a clear pattern of genetic differentiation.Our study provides valuable genetic markers for ecological,genetic,and evolutionary study of these two weevils.