| Titles |
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English :
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EFFICIENCY OF CERTAIN INSECTICIDES ON BIOLOGICAL ASPECTS OF Spodoptera littoralis (Boisd.)
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Arabic :
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التقييم الحقلى لبعض المبيدات الحشرية ودراسة تأثيرها على بعض الصفات البيولوجية لدودة ورق القطن
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| Abstract |
Field experiments were carried out in 2011 cotton season at Sakha Agricultural Research Station, Kafr El-Sheikh to study the efficacy of spinosad, lufenuron and chlorpyrifos against the egg masses (24, 48 and 72 hr age) of the cotton leafworm. Semi field bioassays technique were used to determine the initial and residual activity of these insecticides against 2nd and 4th instars larvae of the field strain of Spodoptera littoralis. The sublethal concentration of spinosad, lufenuron and chlorpyrifos on some main biological aspects of 4th instar larvae of laboratory strain of S. littoralis were studied. Data reveled that spinosad was efficient on the three ages of egg masses compared with chlorpyrifos which gave average percent mortality 50.67, 40and 30.67%, respectively, after three days from spray, while lufenuron came the second order recording 42.67, 44.0 and 22.67% mortality on 24, 48 and 72 hours age egg-masses , respectively. The mortality percentage decreased with increase of age eggmass. With respect the semi-field bioassay technique, the data showed that the general mean of initial and residual activity of the tested compounds on 2nd instar larvae exhibited (93 and 69.18%), (100 and 89.9%) and (100 and 33.76%) for spinosad, lufenuron and chlorpyrifos, respectively. Concerning the effect of the tested compounds against the 4th instar larvae, the data confirmed that the average of larval mortality could be arranged descendingly as follow, lufenuron (77.84%), spinosad (67.16%) and chlorpyrifos (26.12%) mortality. With regard to the above mentioned results, it could be concluded that lufenuron has high toxicity against larval stages of cotton leafworm, came in the second order spinosad has been found to be highly active on all stages of this pest. With respect of toxicity and latent effects of the tested compounds against laboratory strain of 4th instar of S. littoralis, lufenuron was superior effective with LC50 of 0.25 ppm followed by spinosad was giving7.15 ppm, while chlorpyrifos was the least effective one with LC50 of 20 ppm. Concerning the effect of LC25 on the biological aspects of the 4th instar larvae, the data showed that spinosad proved to be the most effective compound in reducing the percent pupation and deformed pupae where causing (82.0 and 18.9%) as compared with (96.4 and 3.3%) for control, while chlorpyrifos was the least effective ones causing (86.8 and 12.98%). Lufenuron nullified adult emergence from treated larvae.
In conclusion, spinosad and lufenuron can be included with other compounds in a frame of IPM programs in which the dependency on the conventional insecticides can be minimized to avoid their known expected harmful effects.
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| Publication year |
2012
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| Pages |
387-398
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| Organization Name |
Plant Protection Research Institute (PPRI)
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| City |
القاهرة
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| serial title |
مؤتمر القاهرة الدولى لسياسات الادارة النظيفة للآفات
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| Author(s) from ARC |
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| Agris Categories |
Pests of plants
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AGROVOC
TERMS |
Bioassays.
Efficiency.
Insecticides.
Spodoptera littoralis.
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| Publication Type |
Conference/Workshop
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