Frass Research Articles

Morphological and chemical analysis of Hylotrupes bajulus (old house borer) larvae-damaged wood and its FTIR characterization

In this study, the biodegradation of wood and chemical changes caused by the Hylotrupes bajulus beetle were revealed for the first time using FTIR spectroscopy. In the study, Scots pine (Pinus sylvestris), fir (Abies nordmanniana), and spruce (Picea orientalis) wood species were exposed to damage by H. bajulus larvae for four months. Morphological measurements and chemical analysis were carried out for the fine powdery dust (FPD) and frass (FR) produced by H. bajulus and compared to control samples. In addition, the FPD and FR of the larvae were examined by FTIR analysis and changes in the wood structure were determined. According to the morphological measurement data obtained from the study, the dimensions of the larval FR were 1 × 0.55 mm screened at 20-mesh, and 0.37 × 0.24 mm at 60-mesh. Holocellulose analysis showed that less holocellulose was detected in the FR and FPD than in the control wood. In the sugar analysis performed via HPLC, the glucose, xylose, galactose, mannose, and arabinose components decreased compared to the control wood, whereas the content of acid-insoluble lignin increased. The FTIR spectra of the wood species (especially in Scots pine) showed that the carbohydrate band intensity at 1735, 1370, 1321, and 897 cm−1 decreased and the carbohydrate bands at 1735, 1321, 1369, and 897 cm−1 were nearly absent in the FPD and FR after H. bajulus larva degradation. However, absorption band intensity at 1508, 1458, 1268, and 1031 cm−1 related to the lignin bands increased significantly. According to these results, H. bajulus larvae degraded cellulose and hemicellulose from the wood components, but they did not degrade lignin.

How fresh is that frass

Many insects inhabit concealed locations such as within timber but leave outward signs of their presence such as frass Deposits of fresh frass on the outside of infested material would indicate a high probability of live insects being present within A method for estimating the age of frass could therefore be useful for assessing treatment efficacy For example the success of termite eradication could be monitored by regularly checking for the presence of fresh frass near old colonies Similarly the presence of fresh frass in borer holes in fumigated timber would raise concerns that the fumigation had been ineffective This study examined whether the age of frass could be estimated from levels of esterase enzyme activity in frass of four species; the termites Stolotermes inopinus and Kalotermes brouni and the weevils Sitona lepidus and Listronotus bonariensis With the termites active esterases were found in 1dayold frass but not in 1monthold frass indicating clear potential for development of a test With the weevils esterase activity occurred both in 1dayold frass and in 1monthold frass so development of a method for these species requires a faster degrading enzyme

Response of the fruit fly parasitoid Diachasmimorpha longicaudata to host and host‐habitat volatile cues

AbstractChemical information is crucial to insect parasitoids for successful host location. Here, we evaluated the innate response of Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae), a fruit fly larval parasitoid, to cues from host and host habitat (i.e., fruit infested with host larvae). We first assessed the preference of female parasitoids between oranges infested with Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) and non‐infested fruit. Females were highly attracted towards infested oranges on the basis of volatile chemical cues. After this initial experiment, we aimed at revealing the potential sources of volatile cues present in an infested fruit. To this end, we considered five potential sources: (1) punctured fruit; (2) fly feeding, frass, or host‐marking pheromone deposited on the orange surface; (3) larval activity inside the fruit; (4) the larvae themselves; and (5) fungi associated with infestation of oranges. Habitat cues associated with host activity and those produced by rotten oranges or oranges colonized by fungi were highly attractive for female wasps, whereas odours associated with the activity of the adults on the surface of the fruit, and those released by the fruit after being damaged (as happens during fruit fly egg‐laying) were not used as cues by female parasitoids. Once the female had landed on the fruit, direct cues associated with larval activity became important although some indirect signals (e.g., products derived from larval activity inside the fruit) also increased host searching activity. Our findings indicate that naïve D. longicaudata uses chemical cues during host habitat searching and that these cues are produced both by the habitat and by the host larvae.

Evidence for an aggregation pheromone in adult frass of banded fruit weevil, Phlyctinus callosus (Schoenherr) (Col., Curculionidae)

AbstractA dual‐choice olfactometer is described in which laboratory bioassays were conducted to test the response of adults of banded fruit weevil, Phlyctinus callosus, to frass from adults of both sexes. Mixed‐sex frass, male frass and female frass were highly significantly attractive to the adults. Both sexes were attracted, although significantly more males than females were attracted to male frass. Evidence strongly suggests that the attractive component in the frass is an aggregation pheromone. This is the first record of chemical communication in this species. These results have prompted an investigation into the chemical analysis of P. callosus frass.ZusammenfassungNachweis eines Aggregationsduftstoffes in Exkrementen des gestreiften Rüsselkäfers, Phlyctinus callosus (Schoenherr) (Col., Curculionidae)Ein Doppelwahl‐Olfaktometer wird beschrieben, worin Labor‐Bioassays ausgeführt wurden, um das Verhalten des gestreiften Rüsselkäfers, Phlyctinus callosus (Schoenherr), gegenüber Käferexkrementen beider Geschlechter zu prüfen. Exkrementgemische beider Geschlechter, Exkremente von Männchen und von Weibchen waren höchst signifikant anlockend für die Käfer. Beide Geschlechter wurden angelockt, obwohl signifikant mehr Männchen als Weibchen durch die männlichen Exkremente angezogen wurden. Es bestehen deutliche Hinweise, daß die Lockkomponente in den Exkrementen ein Aggregationsduftstoff ist. Es sind die ersten Beobachtungen einer chemischen Kommunikation in dieser Spezies. Diese Ergebnisse sollten zu einer intensiven Untersuchung der chemischen Analyse von Exkrementen des P. callosus führen.

Frass Studies of the Armyworm, Pseudaletia unipuncta1

Experiments conducted from 1956 to 1959 showed: (1) Frass pellets of the larvae have characteristic shapes and sizes which can be used as accurately as head-capsule measurements for determining the various instars; (2) Frass-pellet measurements in successive instars fit approximately to a geometric progression with an average ratio of 1.8; (3) Frass contains water-soluble substances and, when exposed to rainfall, may lose from 2% to 35% of its weight, depending upon the instar, though its volume is not affected; (4) At 62° F. the duration of the larval life span was almost double that at 72°, but the number of frass pellets produced increased only slightly; the total weight of frass was higher at 62° and the pupal weights were lower than for individuals reared at 72° : and (5) Temperature was the most important of the factors affecting frass yield.