A survey of parasitoid species within Eriogyna pyretorum (Lepidoptera: Saturniidae) in Fuzhou Region of China

Eriogyna pyretorum Westwood is a notorious defoliator of Cinnamomum camphora (L.) J. Presl that causes large economic and ecological losses in planted forests. To understand the importance of suppress population of E. pyretorum on natural parasitoids, a two-years investigation was conducted in the field. Four parasitoid species were identified from E. pyretorum: Gregopimpla himalayensis (Cameron, 1899), Theronia depressa (Gupta, 1962), Xanthopimpla konowi (Krieger, 1899) and Kriechbaumerella longiscutellaris Qian et He. G. himalayensis and T. depressa were first reported parasitoid wasps within E. pyretorum. Parasitism rates were 18.76% for K. longiscutellaris, 2.10% for G. himalayensis, 7.55% for T. depressa and 0.83% for X. konowi. Longevity, offspring and sex ratio were compared in four hymenopteran species, and K. longiscutellaris was the abundant parasitoid of E. pyretorum in Fujian province of China.

Effects of Wolbachia Infection, Parasitic Order, And Time Interval On The Outcome of Inter-Strain Intrinsic Competition Between Bisexual Strain And Wolbachia-Induced Thelytokous Strain of Egg Parasitoid, Trichogramma Dendrolimi

Parasitoids may deposit a second clutch of eggs on a host that has been parasitized by the same parasitoid species. This is termed “superparasitism”. Wolbachia infection increases the superparasitism frequency of Trichogramma females. We investigated the outcome and fitness cost of inter-strain intrinsic competition between Wolbachia-infected thelytokous strain (TDW) and uninfected bisexual strain (TDB) of Trichogramma dendrolimi. To determine the developmental rate of both strains, the size of immature stages of T. dendrolimi offspring at different times after parasitization was measured in single parasitism and superparasitism conditions. The results showed increased superparasitism by Wolbachia-infected females compared to uninfected females, regardless of the time interval between oviposition; Trichogramma females were unable to distinguish between host eggs previously parasitized by TDB or TDW females. When the first oviposition was performed by TDB females, the TDB offspring outcompeted TDW offspring deposited later. However, although the TDW offspring was deposited 8 h earlier than the TDB offspring, it gained no advantage over TDB offspring. Regardless of parasitism conditions, the differences in development rate and time between TDW and TDB offspring were not significant. This study revealed that albeit TDW females presented a higher tendency of superparasitism than TDB females, TDB offspring outcompeted TDW offspring even when the latter was deposited 8 h earlier. The negative effects of Wolbachia infection on the competitive ability of TDW offspring inside the host eggs were due to offspring’s low fitness rather than delayed development.

Parasitoids of the uniquely social colletid bee Amphylaeus morosus (Hymenoptera: Colletidae) in Victoria

Understanding how nest parasites contribute to brood mortality rates in host species is an important step towards uncovering the potential implications for host behaviour. This can be especially important for understanding the evolution of social living, where defence against parasites is often posited as a major benefit of cooperative nesting. Only two parasitoid species have previously been reported for the only known social colletid bee, Amphylaeus morosus: the gasteruptiid wasp, Gasteruption primotarsale, and the mutillid, Ephutomorpha tyla. Here we report six additional parasitoid species of A. morosus: the gasteruptiid wasps G. atrinerve, G. globiceps, G. melanopoda and G. cinerescens; the bombyliid fly Anthrax maculatus; and the mutillid wasp Ephutomorpha aff. varipes. The mechanisms of parasitism for these eight parasitoid species are described in combination with how they operate throughout the host brood rearing period and whether benefits of social nesting vary across the season.

Effects of productive management of an agroforestry system on the associated diversity of parasitoids (Hymenoptera: Braconidae)

The overuse of pesticides, landscape fragmentation and poor environmental management practices have contributed to the drastic decline of Neotropical unique biodiversity. Parasitoid wasps are widely used as biological control agents, however little is known about the effects of land use and degradation on parasitoid species richness and abundance. This work explores how parasitoid species richness is affected by agroecosystems in which plant diversity is limited (crops; crops adjacent to secondary vegetation). It was found that there is no direct effect of plant diversity in the group of parasitoids studied; however, the number of specialist species (koinobionts) was high, which indicates that diversified agroecosystems probably function as remnants of natural habitat. Future research could help further understand the extent to which landscape fragmentation and plant diversity may alter host-plants interactions and parasitism strategies.

Hymenoptera Parasitoid Diversity in Oil Palm Plantation on PT. Mopoli Raya, Aceh Tamiang, Indonesia

Hymenopteran parasitoids are biological control agents that contribute mortality to economically important pest of oil palm plantations. In this research we investigated the diversity and abundance of Hymenopteran parasitoids at PT. Mopoli Raya, Aceh Province, Indonesia. Data were collected by adopted a purposive sampling method in mature and immature plantations by using light trap, malaise trap, and yellow-pan trap. Specimens were identified at Universitas Syiah Kuala and final taxonomic confirmation was conducted at Gadjah Mada University. We found that the species richness and evenness of the Hymenoptera parasitoid species in mature oil palm plantations tended to be higher than in immature plantations. It is suspected that in immature oil palm plants (4 years) synthetic pesticide application is more intensive and it has a negative impact on the presence of parasitoids compared to the mature.

Performance of Two Trichogrammatid Species from Zambia on Fall Armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a noctuid moth native to the tropical and subtropical Americas that has successfully invaded Africa and Asia, where it is has become a serious threat to food security as a pest of cereals and other crops. Biological control is an environmentally friendly means of combating the pest and contributes to an integrated pest management approach. In our study, two egg parasitoid species (Trichogramma mwanzai and Trichogrammatoidea lutea) found in parasitized fall armyworm eggs in Zambia were identified by using a combination of both molecular and morphological characteristics. To evaluate their potential and efficiency on 0- to 2-day-old fall armyworm eggs, we compared their parasitism capabilities with three Trichogramma species native to China (T. ostriniae, T. leucaniae and T. japonicum) under laboratory conditions. The results showed that both parasitoid species would accept 0-, 1- and 2-day-old fall armyworm eggs, and complete their development successfully. Trichogramma mwanzai and T. lutea preferred parasitizing 0- and 1-day-old eggs over 2-day-old eggs. Trichogrammatoidea lutea females supplied with fall armyworm eggs produced the highest parasitism rate of host eggs among the five tested species, while T. mwanzai had the shortest developmental time on all test age eggs. In general, T. lutea was the best performing of the five species when reared on fall armyworm eggs, while T. japonicum was the worst. There were no significant differences, however, in percent emergence in the five test species when reared on fall armyworm eggs.

The impact of parasitoids on diamondback moth in Europe: a life table approach

Diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), was first recorded in North America from Europe about 150 years ago and can be a significant pest of canola in Western Canada. Because parasitism of P. xylostella in Canada is generally low, the introduction of one or more additional exotic parasitoids from Europe is being considered to increase the suppression of P. xylostella populations. Life table studies to determine the impact of parasitoids on diamondback moth populations in Europe were conducted in northwestern Switzerland in 2014–2016. Net reproductive rates were found to be less than one in seven out of eight life tables, suggesting that P. xylostella populations in Switzerland are mostly driven by immigration and recolonisation. In total, seven primary parasitoid species and one hyperparasitoid were associated with diamondback moth. Pupal parasitism by D. collaris reached up to 30%, but because generational mortality was mainly driven by abiotic mortality factors and predation of larvae, the overall contribution of pupal parasitism was low (< 6%). In regions of Canada, where P. xylostella may have increasing populations and low larval mortality, the addition of D. collaris may be a promising approach. Life table studies across Canada are necessary to determine the need for such intervention.

Short Communication: Silba adipata (Diptera: Lonchaeidae) parasitoids on cayenne pepper (Capsicum frutescens) in Bali, Indonesia

Yuliadhi KA, Supartha IW, Darmiati NN, Bangun A, Yudha IKW, Utama IWEK, Wiradana PA. 2021. Silba adipata (Diptera: Lonchaeidae) parasitoids on cayenne pepper (Capsicum frutescens) in Bali, Indonesia. Biodiversitas 22: 3929-3935. The black fig fly (Silba adipata) is newly emerging pests that attack cayenne pepper (Capsicum frutescens L.) plants in Bali Province, Indonesia. This study aimed to determine the parasitoid type, community structure, distribution, and parasitization rate of the parasitoids of S. adipata on cayenne pepper in Bali. The sampling method employed in this study involves purposive sampling techniques on 100-150 pieces of cayenne pepper infested with S. adipata at each location point, with the emerging parasitoids identified morphologically. Three types of parasitoid species were associated with S. adipata, which include Asobara japonica Belokobylskij, Fopius arisanus (Sonan), and Diachasmimorpha longicaudata (Ashmead). The parasitoid community structure associated with S. adipata had a low abundance index, low diversity index, and a moderate dominance index. Based on the distribution of the three parasitoids, D. longicaudata is distributed evenly in Bali, whereas F. arisanus was not found in Jembrana . Conversely, A. japonica was only found in Badung, Bangli, Gianyar, and Klungkung. As summary, D. laungicaudata had the highest parasitization rate compared to the F. arisanus and A. japonica. D. longicaudata is a potential parasitoid, which can be studied for the future biological control of S. adipata.