Biological control efficiency can be improved by developing effective mass‐rearing systems to produce large numbers of high‐quality parasitoids. This study explored an alternative host for rearing Sclerodermus brevicornis (Kieffer) (Hymenoptera: Bethylidae), a potential biocontrol agent for the suppression of exotic and invasive wood‐boring longhorn beetle (Coleoptera: Cerambycidae) populations in the European agroforestry ecosystems. We tested larvae of the rice moth, Corcyra cephalonica Stainton (Lepidoptera: Pyralidae), as host for the parasitoid. We quantified the probability and timing of host attack and parasitism as well as reproductive success, offspring production, and the characteristics of adult offspring. As S. brevicornis is a quasi‐social species (multiple females, communally produced offspring broods), we also explored the effects of varying the number of females to which individual hosts were presented, with the aim of determining the optimal female‐to‐host ratio. As time to host attack can be a limiting factor in S. brevicornis rearing protocols, we tested the use of adult females of another bethylid species, Goniozus legneri Gordh, to paralyse C. cephalonica larvae prior to presentation. We identified the conditions within our experiment that maximized offspring production per host and offspring production per adult female parasitoid. We found that C. cephalonica is suitable as a factitious host and, as it is considerably more straightforward for laboratory rearing than cerambycid species, it is a good candidate for adoption by future S. brevicornis mass‐rearing and release programmes.

Performance of Sclerodermus brevicornis, a parasitoid of invasive longhorn beetles, when reared on rice moth larvae

Corcyra cephalonica: A serious pest of stored products or a factitious host of biocontrol agents?

Eocanthecona furcellata (Wolff) (Hemiptera: Pentatomidae) is an important polyphagous predator of several agricultural, horticultural and forest insect pests. The biology and feeding potential of E. furcellata were investigated on Bihar hairy caterpillar, Spilosoma obliqua (Walker), a lesser known prey under laboratory conditions. Gravid female laid on an average 203.6±12.56 eggs during its life time. Nymphs passed through five instars in 22.25 to 27.25 days and developed into adults. First instar nymphs had the shortest duration (2.5 to 3.25 days) while fourth instar took maximum days (5.5 to 6.5) to complete, while second, third and fifth instars completed in 5.07 ± 0.26, 5.20 ± 0.71 and 5.24 ± 0.39 days, respectively. Female bugs were bigger in size and lived up to 28 days, while males survived up to 18 days when fed on second instar larvae of S. obliqua . Neonate nymphs devoured 1.6 larvae of S. obliqua while second, third, fourth and fifth instar nymphs consumed 7.73, 11.93, 12.13, 18.67 larvae of S. obliqua , respectively. Individual male and female in their adult stage consumed average 84.25 and 125.5 larvae, respectively, and total consumptions were 136.31 and 177.56 larvae during their life-cycle. From the study, it is evident that S. obliqua could be used as an alternative host to mass rear E. furcellata under laboratory conditions when the main host is scarce or not available.

/pdf/biology-and-feeding-potential-of-eocanthecona-furcellata-3jnhd071va.pdf

Biology and feeding potential of Eocanthecona furcellata (Wolff) on its lesser known prey, Spilosoma obliqua (Walker).

The predatory stink bug Eocanthecona furcellata (Wolff) (Hemiptera: Pentatomidae), which is widely distributed in the subtropics and tropics, is a potential biological control agent for lepidopteran, coleopteran, and hemipteran pests. We investigated development of eggs oviposited by E. furcellata females subjected to various photoperiods (i.e., 8L:16D, 12L:12D, and 16L:8D) and temperature regimes (i.e., 26:26, 30:28, 32:30, 34:32, 35:33, and 36:34 °C; temperatures at light and dark phases, respectively) at different developmental stages. Exposure of E. furcellata nymphs and adults to different photoperiods and temperature regimes affected the development of eggs they subsequently oviposited. Temperatures greater than 30 °C induced diapause in a portion of the eggs, as evidenced by the delayed appearance of the black circle and the red spot, characteristics of early and late stage of embryonic development, respectively. The proportion of diapausing eggs generally increased with increasing temperature exposure, whereas it decreased with advancing developmental stage/age at which E. furcellata was subjected to the temperature regime. Although viability of diapausing eggs was lower than that of non-diapausing eggs, diapausing eggs survived longer under high temperatures. The trade-off between survivability and viability may be a strategy to survive unpredictability of summer temperatures.

Exposure of Eocanthecona furcellata (Hemiptera: Pentatomidae) nymphs and adults to high temperatures induces an aestivo-hibernal egg diapause: a strategy for surviving hot summers

Eocanthecona furcellata (Wolff.) is an important predator for several pest associated with agriculture, especially lepidopteran pest. The predatory behaviour of this predator such as approach and attacking, paralyzing, sucking on the prey were recorded. The adult female could paralyzed a larvae 4.7±0.6 seconds and sucked the body sap within 95.3±5.0 seconds. First instar nymph of the stink bug preferred only second instar larvae of looper and group feeding was observed. The incubation period recorded as 7.6±1.1, duration of nymphal stages as 18.4±1.5, longevity of adult male and female were recorded as 30.0±1.9 and 32.8±0.8 respectively. Egg hatchible rate was 94.5% and 96.2% adult survival of E. furcellata were recorded, reared on Coeryra cephalonica . Moreover this study revealed that, in the absence of main host, C. cephalonica could be used as alternative host to mass rear E. furcellata .

Predatory behaviour of eocanthecona furcellata ((hemiptera: pentatomidae) feeding on larvae of hyposidra talaca (lepidoptera: geometridae), a major tea pest of north east india

Eocanthecona furcellata (Wolff.) (Hemiptera: Pentatomidae) is an important predator for several agriculturally important pests. The biology of E. furcellata has been done with several insect pests but there is no report on the laboratory host, Corcyra cephalonica (Stainton). Hence, this study is aimed to understand the biology of E. furcellata Wolff. and its role in mass rearing on laboratory reared pest C. cephalonica Stainton. The analyses showed that the total number of eggs of the predatory stink bug was 44±8 days, incubation period 6±1.05days and the life cycle passed through five nymphal instars with a total nymphal period of about 16±0.64days. Male and female longevity were 12±1.05days and 14±1.09days, respectively, and total longivity period for male and female lasted 32±0.19 and 36+1.90days, respectively. Moreover, this study revealed that C. cephalonica could be used as alternative host to mass rear E. furcellata when the main host is not available.

https://www.entomoljournal.com/archives/2016/vol4issue3/PartE/4-3-147-536.pdf

S Jesu Rajan

Papers

Biology of predatory bug Eocanthecona furcellata Wolff (Hemiptera: Pentatomidae) on Corcyra cephalonica Stainton