Population suppression of Bemisia tabaci (Hemiptera: Aleyrodidae) using yellow sticky traps and Eretmocerus nr. rajasthanicus (Hymenoptera: Aphelinidae) on tomato plants in greenhouses

We conducted three experiments for management of Bemisia tabaci (Gennadius) biotype ‘B’ on tomatoes under greenhouse conditions: (i) vertically placing yellow sticky cards either parallel or perpendicular to tomato rows at a rate of 1 per 3‐m row; (ii) releasing Eretmocerus sp. nr. rajasthanicus once at 30 adults/m² in the high whitefly density greenhouses (> 10 adults/plant), or twice at 15 adults/m² at a 5‐day interval in the low whitefly density greenhouses (< 10 adults/plant); and (iii) using combinations of yellow sticky cards that were placed vertically parallel to tomato rows and parasitoids released once at 30/m² in high whitefly density greenhouses or twice at 15/m² at a 5‐day interval in low whitefly density greenhouses. Our data show that yellow sticky cards trapped B. tabaci adults and significantly reduced whitefly populations on tomato. The yellow sticky cards that were placed parallel to tomato rows caught significantly more whitefly adults than those placed perpendicular to tomato rows on every sampling date. In the treatment where parasitoids were released once at 30/m² in high whitefly density greenhouses, the number of live whitefly nymphs were reduced from 4.6/leaf to 2.9/leaf in 40 days as compared with those on untreated plants on which live whitefly nymphs increased from 4.4/leaf to 8.9/leaf. In the treatment where parasitoids were released twice at 15/m² in low whitefly density greenhouses, the numbers of live nymphs of B. tabaci on tomato leaves were reduced from 2.1/leaf to 1.7/leaf in 20 days as compared with those on untreated plants on which numbers of live nymphs of B. tabaci increased from 2.2/leaf to 4.5/leaf. In the treatment of yellow sticky cards and parasitoid release once at 30/m² in high whitefly density greenhouses, the numbers of live nymphs of B. tabaci on tomato leaves were reduced from 7.2/leaf to 1.9/leaf, and in the treatment of yellow sticky cards and parasitoid release twice at 15/m² at a 5‐day interval at low whitefly density, the numbers of live nymphs of B. tabaci on tomato leaves were reduced from 2.5/leaf to 0.8/leaf; whereas the numbers of live nymphs of B. tabaci on untreated plants increased from 4.4/leaf to 8.9/leaf. An integrated program for management of B. tabaci on greenhouse vegetables by using yellow sticky cards, parasitoids and biorational insecticides is discussed.     

Interactions between the ant Tapinoma nigerrimum (Hymenoptera: Formicidae) and the main natural enemies of the vine and citrus mealybugs (Hemiptera: Pseudococcidae)

Honeydew-excreting hemipterans, such as mealybug pests, can be protected from their natural enemies by tending ants in return for honeydew, thereby compromising the aims of biological control. In this respect, antagonistic interactions between the ant Tapinoma nigerrimum, native to the Mediterranean basin, and the main natural enemies of both the vine mealybug (VMB), Planococcus ficus, and the citrus mealybug (CM), Planococcus citri, were assessed in laboratory conditions. Parasitism of vine and CMs by their respective parasitoids, Anagyrus sp. nr. pseudococci and Leptomastix dactylopii, was negatively affected by the ant T. nigerrimum. Similarly, T. nigerrimum was shown to significantly disrupt the predatory potential of ladybird larvae, Cryptolaemus montrouzieri, when foraging on host CMs. By contrast, the presence of the ant did not negatively influence the predatory activity of C. montrouzieri adults when feeding on CMs. Consequently, the encyrtid parasitoids A. sp. nr. pseudococci and L. dactylopii and the larval stage of the predator C. montrouzieri may be considered as T. nigerrimum-sensitive, whereas the adults of C. montrouzieri may be regarded as T. nigerrimum-resistant predators. Accordingly, the ant T. nigerrimum constitutes a threat to the biological control of mealybugs by either the encyrtids A. sp. nr. pseudococci and L. dactylopii or the larval stage of the ladybird C. montrouzieri. Hence, adequate control of T. nigerrimum is highly recommended before any release of these mealybugs' natural enemies.     

Parasitization of beet leafhopper eggs, Circulifer tenellus, in California

Parasitoids attacking eggs of beet leafhopper, Circulifer tenellus (Baker) (Hemiptera: Cicadellidae), were surveyed at eight sites in southern and central California for 2 years. One site was an insecticide‐free sugar beet field, and the remaining sites were all uncultivated and supported weedy vegetation. At each site, host plants of beet leafhopper were collected and stored until parasitoids emerged from the leafhopper eggs in the vegetation. Vegetation samples included both naturally occurring host plants and sugar beet outplants that were first infested with beet leafhopper eggs in the laboratory and then placed in the field for 2 days. Parasitism generally was highest in summer and lowest in winter. Beet leafhopper eggs were parasitized by the mymarids (Hymenoptera: Mymaridae) Anagrus nigriventris Girault, Polynema eutettexi Girault, P. longipes (Ashmead), Polynema sp., Gonatocerus capitatus Gahan and two Gonatocerus spp. from the litoralis species group, and the trichogrammatids (Hymenoptera: Trichogrammatidae) Aphelinoidea zarehi Triapitsyn, Walker and Bayoun, A. turanica Trjapitzin, A. roja Triapitsyn, Walker and Bayoun, A. anatolica Nowicki and Paracentrobia sp. near P. subflava (Girault). The most dominant were A. nigriventris, A. zarehi and Paracentrobia sp. The intensity of parasitism varied greatly among the sites with peak levels ranging from 13% to 82%. Species composition also varied among sites, especially between the sugar beet field where A. nigriventris was by far the most dominant parasitoid and the uncultivated sites where A. zarehi and/or Paracentrobia sp. usually dominated. Within the uncultivated sites, parasitoid species composition also varied between the sugar beet outplants and the naturally occurring vegetation; A. nigriventris was much more common in the former than in the latter.     

Enhancing Biological Control of Leafrollers (Lepidoptera: Tortricidae) by Sowing Buckwheat (Fagopyrum esculentum) in an Orchard

Two successive trials were carried out in stone-fruit and apple orchards in the summers of 1994-95 and 1995-96 respectively to determine the effect of floral resources on leafroller parasitoid numbers. Orchards were divided into eight blocks, each containing one replicate of a control and a treatment. The treatment had buckwheat (Fagopyrum esculentum Moench) drilled (as 3 m 2 m plots) in the centre of each replicate, while the control areas were kept weed free with herbicides. Catches of parasitoids in yellow pan traps were compared between the control and treatment areas. In the first trial, on average 10 times more parasitoids were captured in the buckwheat plots than in the controls. However, few of the parasitoids were natural enemies of leafrollers; the catches were dominated by Anacharis sp., a parasitoid of the brown lacewing ( Micromus tasmaniae Walker), itself a beneficial insect. Leafrollers were very rare in this orchard, which explains the absence of their parasitoids in the traps. In the second season, with the experiment conducted in an orchard with a history of leafroller populations, higher numbers of Anacharis sp. were again caught in buckwheat than in control plots. However, significantly higher (34% compared with 20%) levels (P< 0.05) of parasitism (by Dolichogenidea tasmanica (Cameron)) of released leafroller larvae were observed in buckwheat plots than in controls, despite the small plot size. Also, higher numbers of D. tasmanica were captured in yellow sticky traps 2 m above the buckwheat than in the equivalent position in the control plots.     

A taxonomic study on the leafhopper genus Scaphoidella vilbaste (Hemiptera: Cicadellidae: Deltocephalinae) from China

All six species of the leafhopper genus Scaphoidella Vilbaste from China are reviewed. Among them, two new species, S. undosa sp. nov. and S. acaudata sp. nov., are described; two new combinations, Scaphoide. unihamata (Li et Kuoh) comb. nov. and Scaphoidella wideaedeaga (Wang et Li) comb. nov. are proposed; and two new synonyms are revealed, Scaphoideus inermis Cai et He (2001) syn. nov. as a junior synonym of Scaphoidella unihamata (Li et Kuoh 1993) and Scaphoideus multipunctus Li et Dai (2004) syn. nov. as a junior synonym of Scaphoidella stenopaea Anufriev (1977). A key is given to separate all six Chinese species, and illustrations of genitalia are provided.     

Natural enemies for the cabbage webworm,Hellula undalis (Fabr.) (Lepidoptera: Pyralidae) in Malaysia

Four species of larval parasitoids were reared from larvae of the cabbage webworm (CWW),Hellula undalis (Fabr.) (Pyralidae: Glaphyriinae) collected from various cruciferous plants and a capparidaceous weed,Cleome rutidosperma (DC). On cabbage, only two species were recorded,viz, Bassus sp. (Braconidae) andTrathala flavoorbitalis (Cam.) (Ichneumonidae). The other parasitoids were braconids,Chelonus sp. andPhanerotoma sp. Egg or pupal parasitoids were not recorded. The parasitoids were not an important mortality factor of CWW on cabbage because they were usually present at the end of the crop season and their numbers were generally low. On the other hand, predator-exclusion experiments indicated that predators were important in determining the density of CWW on cabbage and the within-generation survival in the field. The major predator was the fire-ant,Solenopsis geminata (F.), which foraged on the prepupae and pupae.     

Comparative life table analysis of Trichogramma bournieri Pintureau and Babault and Trichogramma sp. nr. mwanzai Schulten and Feijen (Hym., Trichogrammatidae) from Kenya

Abstract: Egg parasitoids of the genus Trichogramma (Hym., Chalcidoidea: Trichogrammatidae) have been successfully utilized for biocontrol of several lepidopteran pests world‐wide. Trichogramma bournieri Pintureau and Babault and Trichogramma sp. nr. mwanzai Schulten and Feijen, which are native to Kenya and recovered from Chilo partellus eggs, were compared with the aim of evaluating them for field releases in Kenya for the control of lepidopteran pests, particularly Helicoverpa armigera and Plutella xylostella in tomato and kale, respectively. Age‐specific life tables were constructed at the Institute for Biological Control (BBA), Darmstadt, Germany in 1999 using a cohort of 60 mated females each at 26 ± 1°C, 70 ± 10% relative humidity and 16 h light : 8 h dark photoperiod. The adult female performance and population growth statistics with associated standard errors were computed. There was no significant difference in adult longevity between selected strains of the two species. Trichogramma sp. nr. mwanzai showed significantly higher cumulative as well as daily mean fertility (75.97 and 18.11, respectively) compared with T. bournieri (47.83 and 13.24, respectively), and the respective proportion of female progenies were 52 and 72%. The intrinsic rate of natural increase was 0.309 and 0.306, while the net reproductive rate was 35.16 and 31.22 for T. sp. nr. mwanzai and T.bournieri strains, respectively. The study has also shown that there is no significant difference in the intrinsic rate of natural increase and the net reproductive rate between the two native species. In summary, there is difference between the two strains in their parasitization potential but not in population growth potential. Consequently, no preference can be given to one species when selecting for mass rearing purposes. Adult female performance is superior in T. sp. nr. mwanzai than in T. bournieri. Hence, the former strain should receive particular attention in future studies.     

Egg parasitoids (Hymenoptera: Mymaridae and Trichogrammatidae) of Kolla paulula (Walker) (Hemiptera: Cicadellidae) in Taiwan

Pseudoligosita nephotetticum (Mani) (Hymenoptera: Trichogrammatidae) and Gonatocerus (Cosmocomoidea) sp. (Hymenoptera: Mymaridae) have been identified for the first time as egg parasitoids of the sharpshooter leafhopper Kolla paulula (Walker) (Hemiptera: Cicadellidae: Cicadellinae: Cicadellini) in Taiwan. K. paulula has been recently identified as a candidate vector of the phytopathogenic bacterium Xylella fastidiosa, the causative agent of Pierce's disease of grapes and similar diseases of other affected plants in Taiwan, and thus has become of particular economic importance. Also provided is a summary of the known records of egg parasitoids (Mymaridae and Trichogrammatidae) of other leafhoppers from the tribe Cicadellini in the world, as well as taxonomic notes on P. nephotetticum.     

Identification of egg parasitoids of rice leafhoppers and planthoppers (Hemiptera: Cicadellidae and Delphacidae) of economic importance in Taiwan,part 2: Trichogrammatidae (Hymenoptera)

Trichogrammatid egg parasitoids (Hymenoptera: Trichogrammatidae) of rice leafhoppers and planthoppers (Hemiptera: Cicadellidae and Delphacidae) known from Taiwan are identified taxonomically and illustrated, and their host associations are determined by rearings using sentinel eggs of the key pest species. The previously published records of such egg parasitoids in Taiwan are critically analyzed in the unfortunate absence of almost any voucher specimens. Pseudoligosita nephotetticum (Mani) is shown to be the most common egg parasitoid of the two leafhopper and three planthopper pests of rice in Taiwan: the zig-zag leafhopper Maiestas dorsalis (Motschulsky) (a new host record), the green rice leafhopper Nephotettix cincticeps (Uhler), and the delphacids Laodelphax striatella (Fallén) (small brown planthopper), Nilaparvata lugens (Stål) (brown planthopper), and Sogatella furcifera (Horváth) (whitebacked planthopper). Paracentrobia (Brachistella) andoi (Ishii) syn. nov., originally described from Japan as Japania andoi Ishii, and Paracentrobia (Brachistella) garuda Subba Rao syn. nov. from Thailand are synonymized under Paracentrobia (Brachistella) bicolor (Girault) from northern Queensland, Australia; Pseudoligosita tachikawai (Yashiro) syn. nov., originally described as Oligosita tachikawai Yashiro from Japan, is synonymized under Pseudoligosita nephotetticum. Lectotypes are designated for Japania andoi and Oligosita shibuyae Ishii.     

Performance of Trichogrammatoidea sp. nr lutea Girault (Hymenoptera: Trichogrammatidae) collected from Mussidia spp. in Kenya on eggs of six lepidopteran hosts

Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae), an important pest of maize ears in West Africa, has never been reported to attack crops in East and southern Africa (ESA), though it was found on various wild host plants in these regions. It was suggested that in ESA M. nigrivenella might be under natural control. In Kenya, exploration for natural enemies associated with Mussidia spp. yielded several parasitoids including a trichogrammatid egg parasitoid, Trichogrammatoidea sp. nr lutea Girault. The ability of T. sp. nr lutea to attack the eggs of several lepidopteran species found in Kenya was studied. The lepidopterans included the noctuids Busseola fusca (Fuller) and Sesamia calamistis (Hampson), the pyralids Eldana saccharina Walker, Mussidia fiorii Cecconi and de Joannis and Mussidia‘madagascariensis’, and the crambid Chilo partellus (Swinhoe). The former three species also infest cereals in West Africa. Trichogrammatoidea sp. nr lutea successfully attacked and developed in eggs of all six species indicating its potential to exploit other lepidopteran pests of maize in West Africa. Busseola fusca and S. calamistis were the most suitable hosts and had the largest number of eggs parasitized and progeny per female wasp where E. saccharina and C. partellus were the poorest hosts. The host species used to rear the parasitoid and the age of egg also significantly affected the total number of host eggs parasitized by the parasitoid. It was concluded that the ability of T. sp. nr lutea to exploit lepidopterans that are also pests of maize in West Africa may enhance biological control of M. nigrivenella and it should be considered for translocation to that area from Kenya.     

Ecological and morphological characteristics of endoparasitoids on Elcysma westwoodii (Vollenhoven) (Lepidoptera: Zygaenidae)

Six species of insect endoparasitoids were identified from Elcysma westwoodii, which is the most damaging lepidopteran pest of Prunus yedoensis. From Hymenoptera, two species were identified: a species in Braconidae and Charops striatus in Ichneumonidae. From Diptera, there were four species in Tachinidae: Compsilura concinnata, Exorista sp., Pales sp. and Tachinidae spp. The parasitic ratio was 4.86% (45 of 926 larvae). The hymenopterans were parasitic on 31 individuals of E. westwoodii (68.9%) and the dipterans were parasitic on 14 individuals (31.1%). It was found that parasitoids from the larvae of E. westwoodii were all either endoparasitoids or larval parasitoids. However, Exorista sp. of Tachinidae was found to be either a larval parasitoid or larval-pupal parasitoid. Additionally, all the identified parasitoids were solitary parasitoids, as only one parasite occurred in a larva of E. westwoodii. Because the larva of E. westwoodii eats and molts after it is parasitized, all the parasitoids were identified as koinobionts. There were no big differences in morphological characteristics and life histories between C. striatus and C. concinnata. However, for Exorista sp. and Pales sp., males took 3–5 days longer to emerge from their pupae and had remarkably longer body lengths than females.     

Biogeography and the evolution of flightlessness in a radiation of Hawaiian moths (Xyloryctidae: Thyrocopa)

Aim Although the ability to fly confers benefits to most insects, some taxa have become secondarily flightless. Insect flightlessness may be more likely to evolve in environments such as islands and other windswept and alpine areas, but this prediction has rarely been tested while controlling for phylogenetic effects. Here we present a phylogeny for the endemic Hawaiian Lepidoptera genus Thyrocopa, which has two flightless species that occur in alpine areas on Maui and Hawaii islands, in order to determine whether the flightless species are sister to each other or represent separate losses of flight. We also explore divergence times and biogeographic patterns of inter‐island colonization in Thyrocopa, and present the first Hawaiian study to sample a genus from nine islands. Location The Hawaiian Islands. Methods The phylogeny is composed of 70 individuals (including 23 Thyrocopa species and 7 outgroup species) sequenced for portions of cytochrome c oxidase subunit I, elongation factor 1α and wingless genes, for a total of 1964 base pairs, and was estimated using both parsimony (paup *) and Bayesian inference (Mr Bayes ). Divergence times were estimated using the beast software package. Results Our results indicate that two independent invasions of alpine habitats with concomitant loss of flight have occurred in Thyrocopa. Based on current taxon sampling, Thyrocopa colonized the Hawaiian Islands slightly before the formation of Kauai. In terms of overall patterns of diversification, subclades generally follow a progression from older to younger islands. The genus has the greatest number of species on Kauai, with species numbers generally decreasing with decreasing island age. Main conclusions Loss of flight ability has evolved twice in a short period of geological time in Thyrocopa, perhaps as a result of low temperatures, high winds and/or a lack of predation pressure. However, several other Thyrocopa species that live on small islands with consistently high winds, such as Necker and Nihoa islands, retain the ability to fly.     

Seasonal surveillance confirms the range expansion of Aedes japonicus japonicus (Theobald) (Diptera: Culicidae) to the Hawaiian Islands of Oahu and Kauai

The Asian bush mosquito, Aedes japonicus japonicus (Theobald) was not known to occur in the Hawaii archipelago until it was identified on the island of Hawaii in 2003. This mosquito species remained undetected on the neighboring islands for 8?years before it was discovered at the Honolulu International Airport on Oahu in 2012. By 2015, four Ae. j. japonicus mosquitoes were collected in the western mountains of Oahu and one was collected in the central mountains of Kauai. The collection of this invasive mosquito species across the neighboring Hawaiian Islands of Oahu and Kauai indicated the need for increased seasonal surveillance on these islands. Following nearly four years of surveillance, Ae. j. japonicus was also confirmed to occur in the eastern mountains of Oahu and in the central mountainous region of Kauai. To expand the knowledge of the spread of invasive mosquitoes species further surveillance is necessary to identify all possible areas where populations of Ae. j. japonicus and other invasive mosquito species occur in Hawaiian archipelago.     

Parasitons of non-target tephritid flies in hawaii: Implications for biological control of fruit fly pests

We surveyed the parasitoid complex associated with four non-pest tephritid flies in Hawaii,Procecidochares alani Steyskal (on the Island of Hawaii), andEutreta xanthochaeta Aldrich,Phaeogramma lortnocoibon Asquith, andTrupanea dubautiae (Byran) (on the island of Kauai). The former two tephritids are deliberatelyintroduced biological control agents of weeds; and the latter two are endemic to the Hawaiian Islands. Ten species of hymenopterous parasitoids in six families were recovered from these four non-pest tephritids. Among these species of parasitoids, six were inadvertently introduced to Hawaii, includingEurytoma tephritidis Fullaway (Eurytomidae),Bracon terryi (Bridwell) (Braconidae),Habrocytus elevatus (Walker) (Pteromalidae),Euderus metallicus (Ashmead) (Eulophidae),Torymus advenus (Osten Sacken) (Torymidae), andEupelmus allynii (French) (Eupelmidae); and three were purposely introduced to Hawaii for classical biological control of economically important pests, includingEupelmus cushmani (Crawford),Diachasmimorpha tryoni (Cameron), (Braconidae), andDiachasmimorpha longicaudata (Ashmead). The relative abundance of parasitoid species and percent parasitism varied with the tephritid hosts. Our findings indicate that future development and implementation of biological control programs against frugivorous tephritids or other pests should consider the potential impact of some of the parasitoids on deliberately-introduced weed control agents. Before we can fully assess the potential impacts of some of the purposely-introduced parasitoids on non-target tephritids, however, effects of the many vagrant parasitoids associated with the non-targets should be thoroughly investigated     

The Hawaiian amphibious caterpillar guild: new species of Hyposmocoma (Lepidoptera: Cosmopterigidae) confirm distinct aquatic invasions and complex speciation patterns

Although aquatic caterpillars are a globally rare lifestyle, we have found them in multiple, independent lineages of the endemic moth genus Hyposmocoma across all of the Hawaiian Islands with flowing water. We formally describe 11 new species of Hyposmocoma that belong to four different larval case types: cone, bugle, medium burrito, and large burrito: Hyposmocoma kahamanoa sp. nov. from Oahu Island, Hyposmocoma kamakou sp. nov. from Molokai Island, Hyposmocoma kahaiao sp. nov. , Hyposmocoma waihohonu sp. nov. , and Hyposmocoma moopalikea sp. nov. from Maui Island, and Hyposmocoma aumakuawai sp. nov. , Hyposmocoma eepawai sp. nov. , Hyposmocoma ipowainui sp. nov. , Hyposmocoma kawaikoi sp. nov. , Hyposmocoma uhauiole sp. nov. , and Hyposmocoma wailua sp. nov. from Kauai Island. We also illustrate and describe in detail the aquatic case‐bearing larva of Hyposmocoma kahamanoa. Despite having similar ecologies as algae and lichen grazers at and below the water line of streams, prior research indicates that species with each case type constitute an independent lineage, with terrestrial sister taxa, and therefore the different groups of species bearing unique case types each represent an independent aquatic invasion. The case‐bearing larvae often occur sympatrically, and on Kauai even species with similar case‐types occur together, suggesting complex patterns of speciation and either past periods of isolation or sympatric speciation. Phylogenetic analysis of 2243 base pairs from two nuclear and one mitochondrial gene for 18 species confirm that each species is endemic to a single volcano, and that morphological divergence within case‐types has not been dramatic. Diversification has been complex, and superficially similar case type lineages are not all monophyletic. Kauai, the oldest but smallest of the major high islands, supports more species in the aquatic guild than any other island, thus island age, rather than size, may be important in generating diversity in this group. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 15–42.     

Ecological disjunction across the sexes in an alloparasitoid: Host requirements,sex ratios and mate localization (Hymenoptera: Aphelinidae)

The larval females of Coccophagus sp. nr gurneyi Compere are primary parasitoids of lantana mealybugs, whereas males develop hyperparasitically through other parasitoids (never their own females), so the species is alloparasitic. Males are seldom even reared from lantana mealybugs (<0.3%, n = 4,212), and have not yet been reared from any other host. Adults were sampled in the field to establish that this species is sexual (by assessing female spermathecal content), and to quantify relative abundance of the sexes around host infestations. Adult males were scarce above hosts (3%, n = 314), but were attracted in relatively high numbers to caged virgin females within those infestations. Caged females outside infestations did not attract males, suggesting that mate attraction requires environmental signals other than those from females. Most females collected in the field above host infestations had sperm in their spermathecal capsules. They presumably had mated with males that developed elsewhere (so mate localization might involve searching across substantial distances). Virgin females were present only early in the day and evidently mate soon after eclosion. Evidence of sperm depletion in mated females was not found. The spatial scale of male and female movements needs to be quantified, but the ongoing movement of individuals (as a consequence of their sex‐related host relationships) seems to be a regular aspect of their ecology. The spatial and temporal dynamics across the sexes illustrates that their abilities to localize one another for mating leaves the sexes free to diverge ecologically, and their sex ratios to vary.     

Endoparasitoids of larval Anomis privata (Lepidoptera: Noctuidae), major pest of Hibiscus syriacus (Columniferae: Malvaceae)

Endoparasitoids of Anomis privata larvae include five species in three families of two orders. In this work, two species of Hymenoptera Braconidae (Cotesia sp., Microplitis sp.), one species of Ichneumonidae (Mesochorus vittator) and two species of Diptera Tachinidae (Exorista (Podotachina) sorbillans, Timavia amoena) were investigated. Of the 261 larvae of A. privata examined, 32 had a parasite, so the rate of parasitism was 12.26%. Parasitism by taxon was the highest, at 10.35% (27 individuals), in Cotesia sp. in Hymenoptera Braconidae. Parasitoids of Braconidae and Ichneumonidae were larval parasitoids. A parasitic insect of Tachinidae was a larva–pupal parasitoid. Solitary parasitoids included Microplitis sp. in Braconidae and E. sorbillans in Tachinidae. Gregarious parasitoids included Cotesia sp. in Braconidae, M. vittator in Ichneumonidae and T. amoena in Tachinidae. There was also a multiparasitoid (T. amoena) and two superparasitoids (Cotesia sp., M. vittator). A larva of A. privata sought feed even after it was parasitized every parasitoid investigated in this study, so five species of parasitoids were all koinobiont.     

Monitoring methods for Diaphorina citri Kuwayama (Hemiptera: Liviidae) on citrus groves with different insecticide application programmes

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a major citrus pest that transmits the bacteria Candidatus Liberibacter asiaticus and Ca. L. americanus associated with huanglongbing (HLB) disease. Diaphorina citri population densities can affect the effectiveness of its monitoring and sampling methods. Thus, we compared different methods for adult D. citri monitoring in groves with and without insecticide application programmes. Four short‐term experiments were carried out, each one lasting four consecutive weeks. In these experiments, sticky cards with different colours (yellow, light green, green and dark green), sweep net, two suction device models, visual inspection and stem tap sampling were assessed. Two long‐term experiments were conducted for 4.5 and 5 years, in which only yellow sticky card and visual inspection for D. citri monitoring were assessed. For the short‐term experiments, psyllids were detected by all monitoring methods during all sampling periods in areas without chemical control. However, in areas with psyllid control via fortnightly and monthly applications of insecticides, only sticky cards, regardless of their colour, were able to detect the presence of D. citri. Similarly, for the long‐term experiments, yellow sticky cards were more effective than visual inspection for detecting and quantifying D. citri in all areas with or without insecticide application. Therefore, in areas where HLB is present and chemical control of psyllid is required, sticky cards are the most reliable option for monitoring D. citri.     

Yellow sticky trap catches of parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) in vegetable crops and their relationship to in-field populations

We examined the relationship of yellow sticky trap captures of Bemisia tabaci (Gennadius) biotype B parasitoids to the local population of parasitoids as measured by leaf samples of parasitized whiteflies and mass release of parasitoids. Traps were placed in experimental collard and cowpea field plots in Charleston, SC, and in commercial organic fields of spring cantaloupe and watermelon in the Imperial Valley, CA. The exotic parasitoid Eretmocerus emiratus Zolnerowich and Rose was released in Imperial Valley fields to ensure parasitoid populations would be present. Bemisia adults were trapped in the greatest numbers on the upper surface of horizontally oriented sticky traps in melon fields. In contrast, the lower trap surfaces consistently captured more Eretmocerus than upper surfaces. Female parasitoids were trapped in greater numbers than males, especially on the lower trap surfaces. Progeny of released exotic Eretmocerus greatly outnumbered native E. eremicus Rose and Zolnerowich and Encarsia spp. on traps. Throughout the season, the trend of increasing numbers of Eretmocerus on traps parallelled the increase in numbers of whiteflies. Over the season, 23-84% of all B. tabaci fourth instars were visibly parasitized by Eretmocerus. The numbers of Eretmocerus caught by traps in cantaloupe were similar in trend to numbers on leaf samples in melons, but not with those in watermelon, where whitefly populations were lower. Parasitoid numbers were low in collard and cowpea samples, and no trend was observed in numbers of parasitoids captured on traps and numbers on leaves for these two crops. Overall, there were no significant correlations between sticky trap catches of parasitoids and numbers of parasitized whiteflies on leaf samples in any test fields. Nevertheless, sticky traps placed within crops may be useful for observing trends in whitefly parasitoid populations at a particular site and for detecting parasitoids at specific locations.