The Effect of Insecticides on Pest Control and Productivity of Winter and Spring Oilseed Rape (Brassica napus L.)

Analysis of oilseed rape stem weevil chemical control using a damage rating scale

“…Thiacloprid and tau‐fluvalinate had the lowest efficacy in our trials, which is in contrast to the results of other researchers. This result for thiacloprid can be partly explained by the SC formulation that was used instead of OD as in some other experiments …”

“…Alpha‐cypermethrin and pirimiphos‐methyl showed lower efficacy, but still achieved satisfying results. In trials conducted in Lithuania during 2005 and 2006 it was shown that deltamethrin + thiacloprid, deltamethrin and alpha‐cypermethrin had a highly significant influence on decreasing the number of exit holes . In the same study, the effects of beta‐cyfluthrin + chlorpyrifos, beta‐cyfluthrin and deltamethrin + thiacloprid were highly significant compared with the control concerning the number of damaged plants and exit holes in 2007 and 2008.…”

“…Usually this is done by counting the larvae in plant stems, by counting the number of imagoes on plants, by dissecting plants and measuring tunnels and assessing damage . It is also possible to carry out assessments by counting the number of exit holes on stems . In cases of late assessments, the number of exit holes can be higher than the number of remaining larvae found in stems on account of the fact that the larvae leave the stems prior to pupation.…”

“…16,38 It is also possible to carry out assessments by counting the number of exit holes on stems. 39 In cases of late assessments, the number of exit holes can be higher than the number of remaining larvae found in stems on account of the fact that the larvae leave the stems prior to pupation. Furthermore, in the case of untimely assessments, the number of larvae might be lower because egg laying can last for several weeks 7,40 and the obtained results are likely to be inaccurate.…”

“…This result for thiacloprid can be partly explained by the SC formulation that was used instead of OD as in some other experiments. 39,42 Alpha-cypermethrin and pirimiphos-methyl showed lower efficacy, but still achieved satisfying results. In trials conducted in Lithuania during 2005 and 2006 it was shown that deltamethrin + thiacloprid, deltamethrin and alpha-cypermethrin had a highly significant influence on decreasing the number of exit holes.…”