الفهرس 
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Abstract
Morphological and biological traits of parasitoid Trichogrammain habiting different agroecosystems The present work was initiated to create morphological and molecular identification for three Trichogrammapo pulation scollected from different Egyptian agroecosystems. Also, biological characteristics such as percentages of parasitism, successive parasitized eggs, adult emerged from parasitized eggs, and female emerged parasitoids, as of very importance in achieving success in biological control programs. The three Trichogramm populations include Trichogrammafrom New Valley (TNV), Trichogramma fromMinia (TM), and TrichogrammafromLuxor (TLux). The main goal of this study isto prove if the native collectedTrichogramma of the same species T. evanescens or of different strains. Results can be summarized as follow: Morphological identification of Trichogramma Using scanning electron microscopy (SEM) and light microscopy (LM) in the present work, morphological structures of male and female parasitoid were illustrated for three collectedgroups ofTrichogramma egg parasitoids, TNV, TM, and TLux. The morphological features include body color, body length, compound eyes, antennae, mouthparts, wings, legs, ovipositor, andexternal male genitalia.
1.1. Body Color
Morphological description for the three collected Trichogramma indicated that the coloration of all monotonous, from yellow to black, without metallic sheen.Body Length Concerning the body length of the three collectedTrichogrammapopulation the male was shorter than female generally. Body length of TM group was (620.06± 59.47μm) significantly larger than TLux group (562.23± 49.59 μm) followed by TNV group (529.15± 58.75μm). Body length of T. evanescens ranged 370–420 μm. So, results inadequate andemphasized that Trichogrammapopulations are of different species rather than T. evanescens, which has been recorded in Egypt by several scientists. Male Antennal measurements Antennal trichiation one of the morphological characters used to identify Trichogramma. Measurements of male antennae include flagellar length (FL), flagellar width (FW), scape length (ScL), and longest seta (LS). Data based on 10 males antenna of TNV, TM and TLux. Male antennal length measurements were differed significantly between the three Trichogrammapopulations and F value reached 8.77** and 5.49** for FL/FW and LS/FW measurements. However, Fvalue 2.55ns was insignificant for FL/ScL measurements. Comparingfinding of the three Trichogrammacollections, maleantennaewithT.evanescens,resultsindicatedmerely adequatemeasurementsFL/ScL.Inaddition, itwas inadequatefor FL/FWand LS/FW.Measurements of T. evanescens include 5.6 ± 0.1 (n = 4), 2.1 ± 0.1 (n = 3) and 3.1 ± 0.2 (n = 4) for FL/FW, FL/ScL and LS/FW, respectively. So, the three Trichogrammapopulations cannot be T. evanescens.
1.4. Wings
The morphological features of the three Trichogramma forewings indicated that TNV differed in stigmal vein than TM and TLux. Male Genitalia Measurements Several authors reported that male genitalia can be used to differentiate between species of egg parasitoid Trichogramma. Measurements of male genitalia include general length (GL), general width (GW), apical distance (AD), basal distance (BD), and apical width (AW). Data based on 10 male genitalia of the three Trichogrammapopulations. Concerning GL/ GW measurement value of T. evanescens measured was2.8 μm. This value is adequate values of 2.87 and 2.82μm for TM and TLuxgroups. However, it was inadequate with TNV group value 2.53 μm. Statistical analysis of GL/ GW measurements of the three Trichogrammapopulations indicated a significant difference between them with F value (3.63*). It is of interest to point herein that GL/ GW measurements a good tool to differentiate between collected Trichogrammagroups. 1.6. Female Abdomenal Measurements Female Abdomenal Measurement of the three Trichogrammacollected,includeabdomenal length (Abdo. Length)in μm and abdomenal area (Abdo. Area) in μm2.The body length of adult female Trichogramma measured from the frons to the tip of the abdomen. Statistical analysis of the data indicated a highly significant difference between the three Trichogrammapopulations with F values 14.08** and 18.21** for (Abdo. Length and Abdo. Area), consequently. Also, the maximum values of (Abdo. Length and Abdo. Area) in TM population (292.63 μm and 59317.95 μm2). This was followed by TNV population (247.09 μm and 42923.65 μm2), while it was less values in TLux population (242.30 μm and 42310.93 μm2). In spite,there is non-significant differences between measurements of TNV and TLuxgroups.
AdultfemaleTrichogrammabody length is positively correlated with fecundityand divided the insects into four quality classes include: Class1>0.421 mm, Class2 0.290- 0.420mm, Class3 0.188 – 0.289 mm and Non-standard <0.187 mm. The measurement values of the three Trichogrammapopulations was 0.247, 0.293 and 0.242 mm for TNV, TM and TLux, consequently. So, the TMpopulation (0.293 mm) considered in class 2 (0.290 – 0.420 mm). However, both the TNV (0.247 mm), and TLux (0.242 mm) populations ranked in class 3 (0.188 – 0.289 mm). By discussing the above-mentioned results concerning morphological features of three Trichogrammapopulations from different Egyptian agroecosystems it is clear expected different strains, subspecies, geographically eco-type or different species. Molecular identification of Trichogramma Genetic differentiation by RAPD-PCR fingerprinting technique Molecular techniques RAPD and ISSR markers were used to distinguish the three Trichogrammapopulations. The three Trichogrammapopulations were separated into two clusters with individual RAPD and ISSR markers. The cluster I included TM and TLux groups, while cluster II included only TNV group. 2.3. Molecular Identification TNV PopulationUsing ITS-2 Region of rDNA Sequencing and Phylogenetic Analysis The TNV population was identified based on the molecular genetics technique using PCR amplification and sequencing of the internal transcribed spacer 2 (ITS2) region of the rDNA. Results confirmed that the Trichogramma sp., used as a biological control in the New Valley is T. turkestanica and not T. evanescensas was known. Biological studies The present work aimed to study the effect of five host S. cerealella (SC) densities on three collected egg parasitoid, populationsTNV, TM, and TLux under laboratory conditions(23±2°C, 70±5 RH %). Biological criteria include percentages of parasitism, successive parasitized eggs, adult emerged from parasitized eggs, and female emerged parasitoids. Results indicated that the increase of egg host density from 5 to 80eggs decreased significantly the parasitism% byTNV and TLuxTrichogramma groups except byTMpopulation the parasitism% increased insignificantly from 5 to 20 eggs host density. So, such research, which indicated that lower densities one of the uses of Trichogramma spp., can be effective in the field, and could be reduced cost. Percentages of Parasitism The maximum parasitism% was 62.68± 8.06 byTLuxTrichogramma followed by 52.32± 6.67 forTMTrichogramma. In this approach, the minimum parasitism% was 49.54± 5.88 byTNVTrichogramma. So, it’s of interest to point herein that both TLux and TMTrichogrammaare used in sugarcane fields against sugar cane borers and TNVTrichogramma used against date palm lepidopterous pests in which no pesticides are used. 3.2. Other Biological Parameters for The Three Parasitoid PopulationsTNV, TM, and TLux in Different Host (SC) Eggs Density The results of biological aspects studied in the present investigation include successive parasitized eggs, adult emerged from parasitized eggs and female emerged parasitoids, for the three parasitoids populations TNV, TM, and TLuxTrichogramma. Results indicated that female emerged parasitoids parameter is considered as one of the most important quality parameter. Since, a sex-ratio of ~50 (F: M) as a quality standard for Trichogramma spp., so, such finding merely looks like in TM population, sex-ratio was 56.12 ±15.27 (F: M). So, the present morphological and biological description in addition to molecular identification for Trichogramma species of Egyptian agroecosystems is of great importance for easy and quick species identification.