جستجوی مقالات مرتبط با کلیدواژه "fipronil" در نشریات گروه "گیاهپزشکی"

Wheat is the most important strategic crop in Iran and the world. Sunn pest Eurygaster integriceps Puton (Hemiptera: Scutelleridae) causes a lot of damage annually. Currently, two groups of IRAC insecticides including pyrethroids and organic phosphorus compounds are recommended against this pest in Iran and other countries infested with the Sunn pest. In this research, different insecticides were selected from the eight insecticide groups of IRAC, and contact bioassay was carried out on two life stages of the Sunn pest. The results showed that among the tested insecticides, Deltamethrin (LC50=2.93 mg a.i./L) as a pyrethroid group, had the most contact toxicity among chemical compounds against overwintered adults of the Sunn pest, and Fenitrothion as an organic phosphorus compound  (LC50=19.4 mg a.i./L) was ranked in the second group. But on the new generation of the Sunn pest, both insecticides were ranked in the same group at 72 hours after exposure (LC50=4-4.6 mg a.i./L). Further investigations revealed that among neonicotinoid insecticides, Thiamethoxam had more contact toxicity and ranked in the next group. Mortality comparison of different insecticides in high concentration (60-20000mg/L) based on commercial formulations showed that Deltamethrin and Fenitrothion insecticides caused 90-100% mortality in both life stages of the Sunn pest. The new insecticides, Spirotetramat, Flonicamid, and Chlorantraniliprole did not show acceptable effectiveness 72 hours after exposure on overwintered and new-generation adults (3.3-43%). Therefore, most of the new insecticides tested for the chemical control of the overwintered and the new generation adults did not have acceptable mortality, and only thiamethoxam insecticide can be studied on Sunn pests in field conditions.

Chemical control against overwintered adults of sunn pest Eurygaster integriceps Put. mostly has low efficacy. Today using insecticides and formulations that have durable toxicity on overwintered adults is more approved, because this strategy can reduce treated area against new generation. This research was conducted with six treatments and four replications in randomized complete block design against overwintered adults of sunn pest in Qazvin (Ismail Abad Agricultural Research Station) at 2007-2008. Emulsions and micro capsules formulations were applied with using motorized knapsack atomizer sprayer and with hands respectively. The treatments included delthametrin EC 2.5%, fenitrothion EC50%, fenitrothion G 5%, fenitrothion CS 20%, fipronil G 0.2% and check, that their effectiveness in controlling on sunn pest adults, new generation adults and nymphs were studied. The delthametrin EC 2.5% was more effective than the other treatments. Most treatments were not able to reduce damaged in the standard level (2%). Thus applying of pyrethroid insecticides such as delthametrin with micro capsulated suspension (CS) formulation can be more affected in chemical control of overwintered adults.

Long –term use of some of insecticides on rice striped stem borer (Chilo suppressalis Walk.) and for the reason the urgency of use of new suspension insecticide an experiment carried out، in paddy fields under condition at Rice Research Institute in Rasht، Iran. Treatments were as follow; 1-FipronilG in first generation 2-Fipronil G. in second generation 3-Fipronil SC in first generation 0. 5 lit. 4-Fipronil SC in second generation 0. 5lit. 5-Fipronil SC in first generation 1lit. 6-Fipronil SC in second generation 1lit. and Control. This experiment was conducted with randomized complete block design (RCBD) in 3 replications. Indexes of measurement were included D. h%، W. h%، the alive larvae percentage before &after the first and the second of pest and yield. The results indicated that the lowest rate of D. h at first generation was with granular 20kg. and suspension one lit. per ha. with 5. 63، 5. 57 percent، respectively. Also، in the second generation، the lowest rate of W. h showed in Fipronil G with 3. 64% and SC 1and 0. 5 lit/ha with 4. 24، 4. 96%، respectively. The yield of treatments، control except had not significant in 1% level. The highest of insecticidal efficiency in first generation، related to in fipronil granular 53. 84 and SC (1 and 0. 5 lit/ha) with 45. 29 and 44. 75، and in second generation، observed with formulations of granular and SC 1lit/ha with 56. 55 and 56. 15 %، respectively. Therefore، when we confronted with population increasing SSB، we can use Fipronil SC (1lit/ha) in second generation.