Journal of Entomological Society of Iran
Year:2000 | Volume:20 | Issue:1|Papers Count:9

Parasitoid wasps, Encarsia formosa Gahan, E. inaron Walker, E. pergandiella Howard, E. lutea Masi, E. adrianae Lopez - A villa, E. porteri Mercet, Eretmocerus mundus Mercet from Aphelinidae and Amitus spiniferus Berthes (Platygastridae); Ladybirds (Coccinellidae) including Clitostethus arcuatus Rossi (Scymninae), Scymnus rubrumaculatus Goeze (Scymninae), Exochomus nigromaculatus Goeze (Chilocorinae), Coccinella septempunctata L. (Coccinellinae) and Hippodamia variegata Goeze (Coccinellinae); a green lacewing, Chrysoperla carnea (Step hens) (Chrysopidae); a predatory fly, Acletoxenusformosus Loew (Drosophilidae); Predatory thrips, Scolothrips longicurnis Priesner and Aeolothrips col/aris Priesner (Aeolothiripidae); and Predatory bugs, Orius albidipennis Reuter (Anthocoridae), Geocoris megacephalus Fieber (Lygaeidae), with their host(s) were identified and described as natural enemies of whiteflies in Isfahan province in 1998-2000. An identification key for these parasitoids was provided as well.

Population fluctuation of walnut aphid, Chromaphis juglandicola (Kaltenbach) was closely evaluated during the 2000 growing season. The studies were conducted in two noncommercial walnut orchards in Karaj (Alborz Research Center and campus of College of Agriculture, Tarbiat Modarres University). Population of aphids were assessed weekly as young nymphs (I and II instars), old nymphs (Ill and IV instars), and adults. Population indices of walnut aphid during the growing season in both sampling sites showed a spring peak, followed by a rapid decline in summer, and ultimate increase in fall. The maximum number were 211.8±13.45 and 81.37±14.11 aphids per leaf in Alborz research center, and College of Agric., in mid May, respectively. Mean aphid per leaf in spring, summer and autumn were 74.93±4.87, 0.73±0.22 and 1.61±0.11 individuals in Alborz Research Center and 33.96±2.20, 1.65±0.11 and 2.77±0.22 in College of Agric., respectively. There was no significant difference between aphid densities in the four cardinal points. The sexual aphids appeared at leaf drop period and mated oviparous aphids deposited their hibernating eggs in the basal cracks of host-tree buds.

In the course of this study, the material of Phaneroptera Serville, 1831 (sensu stricto) in Hayk Mirzayans Insect Museum of Plant Pests and Diseases Research Institute wete examined and reviewed. These include: Ph. albida Walker, 1896; Ph. cretacea Uvarov, 1929; Ph. falcata (Poda, 1761); Ph. gracilis Burm., 1838; Ph. sparsa Stal, 1857. It seems that there have been some misidentifications regarding Ph. Sparsa Stal. The species is distributed mainly in Africa and further extends to some parts of the Middle East. Ceychan reported it as Ph. nana sparsa Stal from Afghanistan in 1969. In few specimens from Kopet - Dagh (Turkmenstan), fore tibia length to pronotum length ratio (TIP index) directed Bei-Bienko to call them Ph. bivittata in 1958. Although the availability of this name is somehow questionable but some authors separate it from Ph. nana sparsa by indicating the T/P index, ie: for Ph. bivittata it is between 1.9 and 2.0 and for the other species it is lower than 1.9. Recently, it has been raised as Ph. sparsa Stal. The above mentioned rate was measured 1.85 for the northern Khorasan and Golestan specimens (near to Turkmenistan) and 1.75±0.63 (M±SE) for 43 specimens from all country. Besides, there are a number of reports of Ph. quadripunctata Brunner from Iran which reidentifed as Ph. sparsa. The illustrated identification key and distribution map of the species in Iran is presented.

The biology of E. quadripustulatus (L.) was studied on P. vovae (Nasanov) at 25±2°C. Incubation period averaged 5.9 days. The 1St, 2nd, 3rd and 4th larval instars averaged 3.37, 2.93, 6.17 and 8.50 days, respectively and the total was 20.97 days. Pupal period lasted 6.13 days. The total developmental time averaged 34.47 days. For studying population dynamics, in each sampling 50 infested branches of cypress tree were shook and adults were counted and its diagram was drew. Its density was low during summer months. Careful microscopic examination of ventral side of the abdomen revealed sexual difference in ever case. This univoltine coccinellid had an obligatory estival diapouse in Shiraz. Adults had variations in colour pattern during a life cycle. In this research. 70.1% of eggs on cypress tree were deposited in small groups of one to five in mealybugs ovisacs. In adition, there is considerable preference to fine mesh of rearing units for oviposition and 73.57% of eggs were laid in this positions in large groups of 13.

The stem borer also known as Sart long horn beetle (A.sarta Solsky) is one of the most important pests of poplar, Plane and Elm trees in Iran. Biological studies on A.sarta was carried out during 1997-2000 in laboratory condition. In these studies, rearing of pest was conducted by releasing the adults in pairs in breeding cages in the laboratory. Fecondity, oviposition and longevity were determined by placing each virgin female with one male in a screen cage. So newly hatched grubs, were reared on freshly cut billets of poplar by releasing them in artificially made slits on bark. Later instars were releaved in artificially prepared galleries in the sapwood of poplar billets. Grubs were transferred to fresh billets every 2-3 months and study was continued up to adults emergenec. Female beetles began to oviposit in 15±2.12 days following emergence with 7.75±1.47 days, as oviposition period. Female laid an average of 21.4±5.6 eggs usually at night in laboratory conditions (25±5°c, 60±5% R.H, 14:10 L.D.). White elliptical eggs hatched 10.75±1.08 days after oviposition and longevity of male was 27±2.7 days while female lived 30.25±2.7 days in laboratory condition. Newly hatched yellowish grubs, usually penetrated into the poplar bark. The larvae when placed in fresh billets, bored deep into sapwood by making broad galleries. These grubs continued feeding for hibernation during December to March. After 4 months, in the following spring they became active again and continued feeding till September. Full - grown grubs made pupal chamber deep in the stem core and pupated. The pupae emerged to adults after 3-4 months in December. Adults stayed in the pupation site over winter and emerged in the next spring. The life cycle completed in two years.

In this study, 7 species of the genus Anacanthotermes distributed in different parts of Iran, were selected. At first quantitative characters were measured with a binocular equiped with micrometer apparatus. Afterward, standard figures and Euclidean distances were calculated. The highest figure of Euclidean distances (5.53) related to A. turkestanicus and A. bagherii, and the lowest related to A. vagans and Anacanthotermes sp. (Golestan population). The phylogenetic study conducted with 5 and 24 characters. In both cases the hypothesis indicating A. bagherii as the lowest species of the genus Anacanthotermes was further confirmed. Dendrograms of phylogenetic analysis also suggest that A. ahngerianus, A. turkestanicus and A. esmailii are derived from the nearest common ancestor following geographical isolation and with the event of speciation in their habitation.