Reza Hosseini

Factors affecting detectability of prey DNA in the gut contents of invertebrate predators: a polymerase chain reaction-based method

This study aimed to determine factors that influence the detection of DNA of Plutella xylostella L. (Lepidoptera: Plutellidae) in the gut contents of arthropod predators when the polymerase chain reaction is used to amplify a diagnostic fragment of the gene coding for cytochrome oxidase subunit I. The effects of temperature, time since feeding, subsequent food intake, sex, weight, and species of predator on prey detectability were studied in the laboratory. Three types of predator were studied: the spider Venator spenceri Hogg. (Araneae: Lycosidae), a bug with sucking mouthparts, Nabis kinbergii (Reuter) (Heteroptera: Nabidae), and a coccinellid with chewing mouthparts, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae). In all experiments, the detectability of prey DNA was negatively correlated with time post‐feeding. The duration of detectability differed among the predator species. The time calculated for median detection success at 20 °C ranged from 49.6 h in V. spenceri to 36.1 h in N. kinbergii and 17.1 h in H. variegata. In H. variegata, but not in V. spenceri, the rate of detection decreased with increasing temperature. Subsequent food intake did not affect the detectability of DNA of P. xylostella in V. spenceri. In H. variegata, sex and weight of the predator did not influence detection of prey DNA. In addition, this study uncovered potential sources of error caused by detection of prey DNA following secondary cannibalistic and intraguild predation. The results provide essential information for the interpretation of prey detection data from field‐collected predators’ gut contents.

Phytoseiid mites (Acari: Phytoseiidae) associated with eriophyid mites (Acari: Eriophyidae) in Guilan Province of Iran

Abstract Nine phytoseiid mite species (Acari: Phytoseiidae) associated with eriophyid mites (Acari: Eriophyidae) from Guilan Province of Iran are reported. Three species represent new records for Iran

Global genetic variation in the Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae) and the endosymbiont Wolbachia: links between Iran and the USA detected

BACKGROUND The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is one of the most serious pests of citrus in the world, because it transmits the pathogen that causes citrus greening disease. To determine genetic variation among geographic populations of D. citri, microsatellite markers, mitochondrial gene cytochrome oxidase I (mtCOI) and the Wolbachia-Diaphorina, wDi, gene wsp sequence data were used to characterize Iranian and Pakistani populations. Also, a Bayesian phylogenetic technique was utilized to elucidate the relationships among the sequences data in this study and all mtCOI and wsp sequence data available in GenBank and the Wolbachia database. RESULTS Microsatellite markers revealed significant genetic differentiation among Iranian populations, as well as between Iranian and Pakistani populations (FST  = 0.0428, p < 0.01). Within Iran, the Sistan-Baluchestan population is significantly different from the Hormozgan (Fareghan) and Fars populations. By contrast, mtCOI data revealed two polymorphic sites separating the sequences from Iran and Pakistan. Global phylogenetic analyses showed that D. citri populations in Iran, India, Saudi Arabia, Brazil, Mexico, Florida and Texas (USA) are similar. Wolbachia, wDi, wsp sequences were similar among Iranian populations, but different between Iranian and Pakistani populations. CONCLUSION The South West Asia (SWA) group is the most likely source of the introduced Iranian populations of D. citri. This assertion is also supported by the sequence similarity of the Wolbachia, wDi, strains from the Florida, USA and Iranian D. citri. These results should be considered when looking for biological controls in either country.

Detection of predators within Brassica crops: a search for predators of diamondback moth (Plutella xylostella) and other important pests

Techniques based on the Polymerase Chain Reaction (PCR) have been shown to be powerful tools for ecological studies of predator-prey interactions. By using developed species-specific primers from the cytochrome oxidase subunit I (COI) gene for six insect pests of Brassica crops (Plutella xylostella, Pieris rapae, Hellula hydralis, Helicoverpa punctigera, Brevicoryne brassicae, and Myzus persicae) trophic relationships of selected predators and their prey in Brassica fields demonstrated the potential of DNA-based techniques to screen predator communities and to identify their prey. In this investigation, all examined predators including Nabis kinbergii (Heimptera: Nabidae), Oechalia schellenbergii (Hemiptera: Pentatomidae), Micromus tasmaniae (Neuroptera: Hemerobiidae), Hippodamia variegata, Coccinella transversalis (Coleoptera: Coccinellidae) and four wolf spider species including Trochosa expolita, Venatrix pseudospeciosa, Venator spenceri and Hogna kuyani (Araneae: Lycosidae) showed polyphagy to some extent. All tested positive for P. xylostella, hence can be considered as predators of this pest. Although, the records of DNA from the guts of predators probably represent instances of real predation, but interpretation of predation data because of some errors is very difficult. There are limitations for this type of interpretation which has been comprehensively discussed in this paper.

Predation rate and numerical response of Aphidoletes aphidimyza feeding on different densities of Aphis craccivora

Predation rate and numerical response are basic to any investigation of predator–prey relationships and key components in the selection of predators for biological control. The density-dependent predation rate and numerical response of Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) to varying densities (5, 10, 20, 40, 60 and 80) of third-instar Aphis craccivora (Koch) (Hemiptera: Aphididae), were studied in laboratory conditions [23±1°C, 70 ± 5% relative humidity (RH), and a photoperiod of 16:8 h L:D. Predation rate data were analysed using the age-stage, two-sex consumption rate software. Net consumption rate (C0) increased by increasing prey density. The lowest and highest net consumption rates were 20.75 and 190.8 prey nymphs at densities of 5 and 80 A. craccivora. The transformation rate from prey population to predator offspring (Qp) increased by increasing prey density. The reproductive numerical response, in terms of eggs laid, increased curvilinearly with increasing prey density. Females laid 121.375 ± 4.301 eggs when exposed to the highest prey density (80) and 52.5 ± 1.544 eggs at lowest prey density (5). It can be concluded that different densities of A. craccivora influenced the reproductive performance of A. aphidimyza in terms of predation rate and numerical response.

A remarkable new plant bug genus and species (Hemiptera, Heteroptera, Miridae, Deraocorinae) from the Australian wet tropics

A new genus and new species of deraeocorine plant bug, Kalamemiris gen. nov. and Kalamemiris collessi sp. nov., is described from Australia. Illustrations of male genitalia, scanning electron micrographs of key characters of the male and female habitus, as well as male genitalic characters are provided. The diagnosis of the new genus is made in comparison to other deraeocorines of the Australian biogeographic region.

A new species of the genus Ectagela Schmidt from Iran (Hemiptera, Heteroptera, Miridae, Phylinae)

A new species of the genus Ectagela Schmidt (Phylinae) from Iran, Ectagela kermanensis sp. nov. is described and illustrated. The type specimens are deposited in the insect collection of the Natural History Museum of University of Guilan, Rasht, Iran.

A new species of the genus Phytocoris (Hemiptera: Heteroptera: Miridae: Mirinae) from western Iran

A new species, Phytocoris (Eckerleinius) hawramanicum sp. nov is described from Iran. A revised dichotomous key to the species of subgenus Eckerleinius Wagner known in Iran and adjacent regions, illustrations of male genitalia and male habitus photographs of this new taxon are provided. Diagnosis of the new species is based on a comparison with other congeneric found from Iran and adjacent countries. The type specimens were deposited in the insect collection of the University of Guilan, Rasht, Iran.

On remarkable Pachylaelaps species with unusual sperm induction system in females (Acari, Mesostigmata, Pachylaelapidae)

Abstract In our study of the pachylaelapid mites from Iran, a new remarkable species, Pachylaelaps (Pachylaelaps) prodigiosus sp. nov., is described and illustrated based on adult stages found in soil detritus of broadleaved deciduous forest habitats. The sperm induction system detected in females of the new species is unusual in having its tubular structures exclusively associated with coxae III instead of coxae IV, as found in all other members of the genus. An adult male of P. (P.) grandis Koroleva, 1977, a similar species with analogous sperm induction system in female, is described for the first time. A new species group in the subgenus Pachylaelaps, represented by P. (P.) grandis, P. (P.) kirghizorum Koroleva, 1977 and P. (P.) prodigiosus sp. nov., is newly constituted, and its specific characters of insemination apparatus discussed.

Genetic Variation of Beet Armyworm (Lepidoptera: Noctuidae) Populations Detected Using Microsatellite Markers in Iran

Abstract In order to understand the population genetic diversity and structure of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), a serious pest of sugar beet in Iran and the world, we genotyped 133 individuals from seven regions in Iran using four microsatellite loci. Significant difference was seen between the observed and expected heterozygosity in all loci. A lower observed heterozygosity than expected heterozygosity indicated a low heterozygosity in these populations. The value of F showed a high genetic differentiation, so that the mean of Fst was 0.21. Molecular analysis variance showed significant differences within and among populations with group variance accounted for 71 and 21%, respectively. No correlation was found between pair-wise Fst and geographic distance by Mantel test. Bayesian clustering analysis grouped all regions to two clusters. These data suggested that a combination of different factors, such as geographic distance, environmental condition, and physiological behavior in addition to genetic factors, could play an important role in forming variation within and between S. exigua populations.