RETRACTED ARTICLE: Efficacy of inundative releases of Trichogramma evanescens in controlling Lobesia botrana in vineyards in Egypt

The present work was conducted to evaluate the efficacy of Trichogramma evanescens (Westwood) in controlling the European grape berry moth Lobesia botrana (Den. & Schiff.) in two vineyards, in El-Beheira and El-Gharbia Governorates, northern Egypt during the 2004 and 2005 seasons. T. evanescens was mass produced on Sitotroga cerealella (Olivier) eggs in National Research Center in Egypt. The horizontal and vertical searching activity of T. evanescens was studied to determine the proper way of distributing the Trichogramma cards in vineyards in 2004. Field experiments were also conducted to evaluate inundative releases of T. evanescens to control L. botrana on large scale in 2005. Parasitism by T. evanescens on L. botrana eggs was greatly affected with the horizontal or vertical distance from the release points. Parasitism reached over 97% and reduction percents of infestation were caused by the pest reached 96.8% in treated plots. A significant increase in the crop was achieved in treated plots. The results showed that the release cards should be distributed in every three grape rows and on height 130–170 cm to obtain good parasitism rates. T. evanescens could be a potential candidate for biological control of L. botrana in vineyards.     

Parasitoid and host egg ages have independent impact on various biological traits in a Trichogramma species

Trichogramma (Hymenoptera: Trichogrammatidae) are species used worldwide for the biological control of Lepidopteran pests, notably through inundative releases on millions of hectares. The optimal use of Trichogramma parasitoids in crop protection requires an accurate knowledge of their biology. More specifically, the importance of age factor in parasitoids during the time they forage in crops for host eggs (after initial release) and how the aging of host eggs could impact parasitoid biological traits may be important for overall efficiency in terms of crop protection. In this context, the importance of parasitoid female and host egg ages on parasitism rate and the development of offspring was studied in laboratory conditions on Trichogramma cacoeciae Marchal (Hymenoptera: Trichogrammatidae) and the eggs of the pest Lobesia botrana Denis and Schiffermüller (Lepidoptera: Tortricidae). Host eggs tested were 1–2- and 3–4-day-old, while the ages of T. cacoeciae adult females varied from 1-day-old to 4-day-old post-emergence. When L.?botrana eggs were 3–4-day-old, they were less parasitized by T. cacoeciae than 1–2-day-old eggs, and this was not linked to the age of T. cacoeciae females. The age of parasitoid females has an effect on parasitism, as 1-day-old females produced fewer parasitized eggs than 2, 3, and 4-day-old females. For the total number of L. botrana eggs killed by T. cacoeciae, the two factors did not show significant effects. When L. botrana eggs were 1–2-day-old, parasitoid emergence increased according to the age of parasitoid females with the highest success observed for 3-day-old females. The lowest emergence rates were obtained with T. cacoeciae females 1-day-old. The development time was also longer with the young 1-day-old parasitoid females. This study demonstrated that both the aging of parasitoids and host eggs play a role in the subsequent development of parasitoid offspring. The importance of these results in the context of biological control programs involving Trichogramma parasitoids is discussed.     

Zur Morphologie und Entwicklung von Bracon instabilis Marsh. (Hym., Braconidae), eines Parasiten der Kartoffelmotte,Phthorimaea operculella Zell. (Lep., Gelechiidae) in Ägypten

Bracon instabilis Marshal is an ectoparasite attacking the larvae ofP. operculella in Egypt. According to available literatures, this is the first study onB. instabilis. The laboratory rearing of this parasite was undertaken on the third and fourth larval instars ofP. operculella and the method was mentioned in details. Certain aspects of the morphology of the immature and adult stages were given. The durations of the immature stages of the parasite were estimated at 15 and 25°C and 60±5% R.H. The total durations of the immature stages (from egg to adult) were 39.62 and 11.19 days at 15 and 25°C, respectively.     

Beziehungen zwischen dem Bakterium Serratia marcescens (Biz.) und der in den Raupen von Sesamia cretica. Led. (Lep., Tortricidae) sich entwickelnden Schlupfwespe Bracon brevicornis Wesm. (Hym., Braconidae)

Laboratory experiments were undertaken to study the interrelationships which may be detected when rearing the ectoparasitoid,Bracon brevicornis onSesamia cretica larvae after being injected with the bacterial pathogen,Serratia marcescens at five constant temperatures. Many effects detrimental to the parasitoid were found through rearing onSerratia-infected larvae ofSesamia e.g. decreased the deposited eggs especially at 35°C; reduced the formed cocoons and produced adults at all temperatures (15–35°C); and prolonged developmental, repriod especially at 20 or 25°C. Number of infected host larvae which allowed complete successful development for the parasitoid was significantly decreased especially at the extremes of temperatures.     

Ecological studies on parasitism ofEretmocerus longipes Compere (Hym., Aphelinidae) on the whitefly,Aleurotuberculatus takahashi David et Subramaniam (Hom., Aleyrodidae) on jasmine in Fuzhou region of the southeastern China

Experiments on host-stage preference, influence of temperature on parasitization, and the feeding niche ofEretmocerus longipes Compere (Hym., Aphelinidae) parasitizingAleurotuberculatus takabashi David et Subramaniam (Hom., Aleyrodidae) on jasmine were conducted both in the laboratory of Institute of Plant Protection, Fujian Academy of Agricultural Sciences and in the field in the Fuzhou region, Fujian Province, PR China. The results showed that the most preferred host-stage ofE. longipes was the 3rd instar ofA. takahashi. The parasitization rate ofE. longipes was significantly affected by temperature, valuing 4.8% at 18 °C, 27.3% at 23 °C, and 55.1% at 33 °C, respectively. The whitefly immature stages and the parasitoid vertically selected all the layers of jasmine plant as their feeding niches, but the whitefly nymph preferred to gather on the top layer, which was considered as its suitable feeding niche, while the parasitoid selected the middle layer as its feeding niche. To measure the ability to utilize spatial resources, the feeding niche breadth was introduced to demonstrate that the parasitoid had the less wide feeding niche breadth among the all stages tested on jasmine, which revealed that the spatial activity for the parasitoid was smaller than that for any stage of the whitefly. The cluster analysis showed that the feeding niche of the parasitoid was more closely related to the 3rd instar than to any other stage of the whitefly. It was suggested that relation between the whitefly and its parasitoid was not only depending on the host-stage preference but also on the feeding niche similarity.     

Lebenszyklus von Meloidogyne incognita acrita (Kofoid & White) Chitwood (Nematoda,Heteroderidae) in Wurzeln der Baumwolle,Gossypium barbadense L

The incubation period ofM. incognita acrita eggs took 24–72 hours till the appearance of the second larval stage hatching from eggs in the laboratory at 25±5°C and at 60±5 R. H. The second larval stage, was observed in cotton roots 48 hours after the addition of it to soil beside cotton seedlings. The 3rd and 4th larval stage and adult female were observed in cotton roots 7, 11, and 24 days, respectively, after the addition of second larval stage to soil beside cotton seedlings. The total life cycle ofM. incognita acrita on cotton, (Gossypium barbadense) lasted for 33–38 days, at 25±5°C and at 60±5 R. H.     

Laboratory studies on the effect of temperature and humidity on the life table of the whitefly,Aleurotuberculatus takahashi David & Subramaniam (Hom., Aleyrodidae) from southeastern China

The present paper deals with developmental duration, emergence, longevity and fecundity ofAleurotuberculatus takabashi David & Subramaniam at different temperatures and humidity levels. The developmental time from egg to adult was 81.8, 56.9, 39.6, 29.9, 20.6 days at 15±1, 20±1, 25±1, 30±1, 35±1°C under constant relative humidity (RH) of 70±5%, respectively. At 25±1°C, the total developmental time was slightly affected by humidity, ranging from 46.4 days at 40±5% RH to 39.2 days at 90±5% RH. The developmental threshold and the thermal constant for the stage from egg to adult were 10.1°C and 542.8 day-degrees. It was estimated that the whitefly has about 10 generations a year in Fuzhou region in southeastern China. Lowest mortality rates of 12.4% for the egg, 6.8% for the nymph and 3.1% for the puparium were obtained at 15±1°C, while they were highest with 92.1% for the egg, 48.2% for the nymph and 36.3% for the puparium at 35±1°C. The mortality rates were slightly affected by humidity, ranging from 17.6% at 40±5% RH to 27.9% at 90±5% RH for the egg, 11.2% at 40±5% RH to 19.6% at 90±5% RH for the nymph, and 6.4% at 40±5% RH to 11.6% at 90±5% RH for the puparium. The emergence rate of adults decreased as temperature increased, ranging from 89.1% at 15±1°C to 21.5% at 35±1°C, so did the longevity of adults, ranging from 9.6 days at 15±1°C to 2.9 days at 35±1°C. The number of eggs per female was significantly affected by temperature (P.01), valuing 29.4 eggs per female at 15±1°C, 36.7 at 20±1°C, 52.4 at 25±1°C, 42.9 at 30±1°C, and 6.1 at 35±1°C. The optimal temperature for reproduction was about 25°C.     

Über die Rotgelbe Tomatenmilbe,Aculops lycopersici (Massee) (Acari,Eriophyidae) in Ägypten

Occurence ofAculops lycopersici and its predators as well as the biological aspects of this pest were studied. The mite was reared on excised leaves ofSolanum nigrum L. in the laboratory at 25±1 °C and R. H. 70%. Duration periods of immatures and longevity of the adult were determined.     

Studies on the predation efficiency ofAgistemus exsertus Gonzalez (Acarina,Stigmaeidae) on the eriophyid miteAculops lycopersici (Massee)

The predacious miteAgistemus exsertus Gonzalez was reared in the laboratory on the eriophyid miteAculops lycopersici (Massee) for studying the development, fecundity and predation efficiency. At 30°C and R.H. 75% the duration of the predator egg incubation, immature stages, life cycle, oviposition and longevity of the adult female was 0.92, 2.10, 3.02, 4.89 and 7.20 days respectively in average. The consumption by one adult female ofA. exsertus per day on the different stages of the eriophyid miteA. lycopersici was 60.3 eggs and 45.3 immature and mature stages.     

Studies on the egg parasitism inThaumetopoea pityocampa over a period of four years (1991–1994) at marikostino/bulgaria

In Bulgaria near Marikostino, in a forest ofPinus nigra Arn. 239 egg batches were sampled over four generations ofThaumetopoea pityocampa (Den. &; Schiff.) (Lep., Thaumetopoeidae) in various seasons. Directly after collection the batches were singled in test tubes, closed with cotton stoppers and stored under laboratory conditions at 20–22°C. Oviposition always started from the base towards the tip of the needles. The emergence of egg parasitoids was observed daily, and the parasitoids were counted and identified. The eggs from which parasitoids emerged were marked for further studies. After removing the adults and opening the eggs, the impact of the species of parasitoids was evaluated by identifying the meconia and other rests (left overs). Ooencyrtus pityocampae (Mercet) was the most abundant egg parasitoid, followed byAnastatus bifasciatus (Fonsc.). Only few individuals ofBaryscapus servadeii (Dom.) were collected. The hyperparasitoidBaryscapus servadeii (Dom.) were collected. The hyperparasitoidBaryscapus transversalis Graham, was found at low densities. Only a few eggs were parasitised byTrichogramma embryophagum Htg. Total mortality of the host eggs varied from 34.7 to 79.7% depending on the period of parasitism and on the numbers of sterile eggs. The impact of the parasitoids was calculated to be 9.3–38.9%, depending on the period when parasitism had taken place. The mean number of eggs per batch varied from 203 to 253. The rate of parasitism was reduced by early sampling of the egg batches. In some cases, a very high percentage (up to 29.2%) of undeveloped eggs was found. In all samples a small percentage of empty eggs was always observed.     

Übertragung zweler bakterieller Pathogene in den Körper von Sesamia cretica Led. (Lep., Tortricidae) mittels des Legebohrers von Bracon brevicornis Wesm. (Hym., Braconidae)

Laboratory trials were undertaken to investigate the transmission of 2 bacterial pathogens (Serratia marcescens Bizio andBacillus thuringiensis Berliner) by the ovipositor of a braconid parasitoid,Bracon brevicornis Wesmael into the body cavity ofSesamia cretica Lederer. The braconid's ovipositor was able to transmit the 2 bacterial pathogens and plays as inoculating needle. The host larvaeS. cretica were significantly immobilized faster by the contaminated ovipositor of a parasitoid (in case of the 2 pathogens). After successful transmission of the bacterial pathogen into the body cavity of host larvae, different deleterious effects were significantly found for the parasitoid and its progeny specially in case ofS. marcescens. Through contamination of the ovipositor, the non-sporeforming bacterium,S. marcescens has more pathogenic effects on the parasitoid and its progeny than the sporeforming bacterium,B. thuringiensis.     

Artificial incubation of Great bustard (Otis tarda) eggs

A trial of artificial incubation to great bustard (Otis tarda) egg was conducted from 1995 to 1997. Among the 45 collected eggs, 28 eggs were fertilized and 26 hatched, with fertilizing rate 62.2% and incubation rate 92.85%. The mean incubation-days for great bustard egg was confirmed as 24.4 (21–28 days) with the formula for caculating fresh egg weight (W=KwLB ²) and that for counting the incubated days by parents birds in field (Id=24(w−y)/0.144y). The proper incubation temperature and relative humidity were 36–37.8°C and 50–65%, respectively. The egg weights and egg size average 130.45 g and 77.4±1.42×55.5±0.65 mm respectively. The total weight loss of egg was 18.38±0.646 g, daily weight loss 0.748±0.071 g in the incubation time, with a weight loss rate of 13.6±1.02%. A linear regression equation to discribe the relationship between the egg weight and incubation days, was built,y=130.73−0.619x (x-incubation day,y-egg weight) r=−0.978. Twenty-eight hours were nassassary for great bustard embryo to complete the fledging when the were put in gas room. The mean weight of fledglings was 86.3±3.29 g(n=26). (Responsible Editor: Chai Ruihai)     

Overwintering ofTrichogramma evanescens Westw. in Egypt (Trichogrammatidae,Hymen.)

Eggs ofA. kuehniella parasitized byT. evanescens were held outdoors in a shadow place during the period from November 20th, up to parasite emergence. Blackness of the parasitized eggs appeared 3 days later.Overwintering lasted for 99 days starting from 24th, November till 2nd of March at an average temperature of 10.1° C. When temperature increased to an average of 16.6° C, the parasitoids continued their development for 5 days till the emergence of adults.Emerged adult parasitoids showed relatively normal bioaspects as those reared in the laboratory.With 2 tables     

Effect of different host plants on the development time and parasitization rate of eretmocerus dehachi rose and rosen (hymenoptera: aphelinidae) withparabemisia myricae (Kuwana) (homoptera: aleyrodidae) as insect host

The effect of six citrus and five non-citrus host plants on the developmental time ofEretmocerus dehachi Rose and Rosen (Hymenoptera: Aphelinidae), the parasitoid ofParabemisia myricae (Kuwana) (Homoptera: Aleyrodidae), was studied under laboratory conditions. On citrus host plants, the mean developmental time from egg to adult was shortest on lemon with 14.6 days and longest on trifoliate orange with 26.3 days. On non-citrus host plants the developmental time ranged between 16.3 days on vine and 23.0 days on pomegranate. Among the various host plants tested,E. dehachi preferredP. myricae on sweet orange. A high mortality ofP. myricae due to host feeding and parasitization was observed on sweet orange and grapefruit among citrus host plants and on rose among non-citrus host plants.     

Über eine neue semisynthetische Nahrung für die Raupen des Bekreuzten Traubenwicklers,Lobesia botrana Den. et Schiff. (Lepid., Tortricidae)

The composition of semisynthetic food according toPodmanická andWeismann (1975) is being introduced. It was used for the first time to breed grape moth,Lobesia botrana Den. et Schiff. The author used it in climatised space at various but constant degrees and relative air humidities (from 20°C to 27°C, relative humidity of air 88,0%±6,0% and at a photoperiod of 16 hours). Ten generations of grape moth were grown. The caterpillars were grown each separately in Petri bowls. The reproduction physiology of imago fed on this food was in comparision with the results of other authors less disturbed. Breeding was 89%, the average output of breeding 80%. Mortality rate in caterpillars 10–15%, chrysalis 3–6%, the average actual fertility 158 eggs. Multiplication coefficient 36,0. The results reached allow the assumption that synthetic food will be a convenient nutrition medium for a mass breeding of grape moth. Less demanding as for its technology and the time needed as well as low cost are the advantages of this semisynthetic food.     

Zur Wirkung der Partikelgröße der Imaginalnahrung auf die Eizahl vonTribolium castaneum (Hbst.) (Col., Tenebrionidae)

Whole and intact wheat grains or those broken into 2 or 8 equal pieces and supplemented with yeast provided as adult food to individuals ofTribolium castaneum considerably reduced the egg output in these beetles although their larvae were reared on finely powdered yeast-supplemented whole wheat flour. However, egg fertility in all the three dietary situations was 100%.     

Reduction in egg hatch ofArgas (Argas) reflexus (Fab.) (Acari,Argasidae) due to colchicine

The eggs ofArgas (Argas) reflexus (Fab.) were exposed to 0.05% colchicine on 9th, 15th or 23rd–25th days of embryonic development at 25°C and 30% RH. The eggs on the 15th and 23rd–25th days of development were the most sensitive to colchicine. In these experiments 6.9% and 9.4% embryos died, respectively. The largest number of disturbances of egg hatch (11.5%) were observed after exposure of the eggs to colchicine on 23rd–25th days of embryogenesis.     

Development and fecundity of <Emphasis Type="Italic">Trissolcus japonicus</Emphasis> on fertilized and unfertilized eggs of the brown marmorated stink bug, <Emphasis Type="Italic">Halyomorpha halys</Emphasis>

Halyomorpha halys, the brown marmorated stink bug, is a serious agricultural and horticultural pest native to East Asia, which became an invasive pest in northern temperate parts of other regions in the mid-1990s. Trissolcus japonicus is a dominant egg parasitoid of H. halys in its native range. In this paper, we investigated mating, oviposition and fecundity of both virgin and mated females of H. halys. Virgin H. halys females produced unfertilized eggs, while mated females produced fertilized eggs, but mating states of adult females did not affect the number of eggs produced. We further compared the development and fecundity of T. japonicus on fertilized or unfertilized eggs of various ages. Fertilized eggs were tested continuously for up to 5 days (time to hatch), while unfertilized eggs were tested for up to 11 days (time to egg collapse). The fertilization status of the host egg had a significant effect on the development, emergence success, and sex ratio of T. japonicus progeny. A small increase in development time was observed for T. japonicus in fertilized eggs, fewer T. japonicus emerged from fertilized eggs than unfertilized eggs, and the proportion of female progeny was lower on fertilized eggs. The age of host eggs also significantly affected the development rate and fecundity of T. japonicus, with unfertilized eggs becoming more favorable than fertilized eggs as egg age increased. In summary, unfertilized H. halys eggs were better suited for T. japonicus development and fecundity, indicating their potential use in T. japonicus mass rearing.     

Influences of host age,sex ratio,population density,and photoperiod on parasitism by <Emphasis Type="Italic">Trichogramma evanescens</Emphasis> Westw. (Hym., Trichogrammatidae)

Moth species Ephestia kuehniella and Sitotroga cerealella are serious pests in cereal-based food processing facilities and stores in Turkey. Control of these pests is undertaken by regular space treatment of infested areas with pesticides. An alternative control method could be the release of parasitic wasps of the genus Trichogramma. In laboratory tests, we use T. evanescens as a parasitic wasp reared on the eggs of Ephestia kuehniella. Adult wasps emerging from the host were maintained in glass tubes at 27±1° C, 60–70±5% r.h and L14:D10 and fed on honey solution. Adults of T. evanescens in vials without food enclosed from host eggs and all died within 1.8days; in comparison, in vials with honey, live adults were evident for 15.2days. Fresh (6–48h) and old (72–96h) host eggs were offered to T. evanescens and fresh eggs were more accepted than old. Host acceptance of females with males in vials was better than without males. The number of females in the vials also influenced the parasitization rate and single female parasitized more eggs. Adults living in light regime (L14:D10 and L6:D18) parasitized more eggs than in total darkness. Results are discussed with relation to enhancing parasitoid effectiveness in biological control in processing facilities and mills.     

Zur Biologie der RaubmilbeCunaxa capreolus Berl. (Acari,Prostigmata, Cunaxidae)

Studies on the biology of the predaceous mite Cunaxa capreolus Berl. (Acari, Prostigmata, Cunaxidae) During life cycleCunaxa capreolus Berlese passes through egg, larva, three nymphal stages and adult. Each moving stage is proceeded by a quiescent one. Biological process such as hatching, moulting and mating were investigated. Female usually deposites its eggs singly in protected places. Number of deposited eggs per female, when fed on book lice (Psocoptera), was positively correlated with temperature. It averaged 24.6, 30.7, 40.7, and 43.5 eggs at 15°, 20°, 25° and 30 °C. Incubation period as well as duration of immature stages and adult longevity were negatively effected with temperature. The generation period (from egg to egg) ranged from 24.8 to 64.2 days when temperature changed from 30° to 15 °C. Within these limits of temperature, the simple regression indicated that an increase of 1 °C decreased the generation period for about 2.6 days.