Bemisia tabaci (Homoptera: Aleyrodidae) instar effects on rate of parasitism by Eretmocerus mundus and Encarsia pergandiella (Hymenoptera: Aphelinidae)
نویسندگان
چکیده
Studies were conducted to compare preference among Bemisia tabaci Gennadius, biotype B instars for parasitization by Eretmocerus mundus Mercet and Encarsia pergandiella Howard when provided one instar only, two different instars, and four different instars simultaneously. In the single-instar no choice treatment, Er. mundus was more successful in parasitizing the younger host instars, while En. pergandiella parasitized a greater proportion of the older instars. Similar results were observed when parasitoids were provided a choice of two instars in six different pair combinations. When all four instars were provided simultaneously, the numbers of first, second, and third instars parasitized by Er. mundus were not significantly different from each other (range 10.3–16.4%), but all were significantly higher than parasitism of fourth instar nymphs (2.1%). The highest percentage parasitization by En. pergandiella was in third instar (17.2%), and the lowest in first instar (2.8%).
منابع مشابه
Taxonomic Position of Iranian Isolates of Eretmocerus mundus (Merect), a Parasitoid of Bemisia tabaci (Gennadius)
Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important pest of vegetable and fruit crops. This polyphagous pest has a range of natural enemies including the parasitoid Eretmocerus mundus (Merect) (Hymenoptera: Aphelinidae). To determine the molecular profile and taxonomic status of Iranian isolates of E. mundus, parasitized B. tabaci samples were collected from cotton...
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