TY - JOUR T1 - Singular and Joint Usage of Third Larval Instars of Hippodamia Variegata (Goeze) and Chrysoperla carnea (Steph.) in Biological Control of Aphis gossypii Glover in Greenhouse TT - استفاده جداگانه و توام لاروهای سن سوم کفش دوزک Hippodamia variegata (Goeze) و بال توری Chrysoperla carnea (Steph.) در مبارزه بیولوژیک شته جالیز Aphis gossypii (Glover ) در گلخانه JF - JCPP JO - JCPP VL - 4 IS - 4 UR - http://jcpp.iut.ac.ir/article-1-118-en.html Y1 - 2001 SP - 119 EP - 128 KW - Hippodamia Variegata KW - Green lacewing KW - Chrysoperla carnea KW - Cotton aphid KW - Aphis gossypii KW - Singular and joint usage. N2 - The efficiency of singular and joint usage of third larval instars of ladybeetle, Hippodamia variegata (Goeze) and green lacewing, Chrysoperla carnea (Steph.) was studied against cotton aphid, Aphis gossypii Glover on cucumber plants in greenhouse. The predator-prey ratio of 1:30 reduced the population of pest significantly. Singular and joint usage of predators, however, was not significantly different. The predator-prey ratio of 1:90 reduced the population of host significantly but the treatment with larvae of both predators and the treatment with only ladybeetle larvae were not significantly different. However, only the treatment with lacewing larvae was significantly different from the two above-mentioned treatments. M3 ER -