Impact of Planting Dates and Insecticide Strategies for Managing Crucifer Flea Beetles (Coleoptera: Chrysomelidae) in Spring-Planted Canola

Abstract

Integration of cultural practices, such as planting date with insecticide-based strategies, was investigated to determine best management strategy for flea beetles (Phyllotreta spp.) (Coleoptera: Chrysomelidae) in canola (Brassica napus L.). We studied the effect of two spring planting dates of B. napus and different insecticide-based management strategies on the feeding injury caused by fleabeetles in North Dakota during 2002-2003. Adult beetle peak emergence usually coincided with the emergence of the early planted canola, and this resulted in greater feeding injury in the early planted canola than later planted canola. Use of late-planted canola may have limited potential for cultural control of flea beetle, because late-planted canola is at risk for yield loss due to heat stress during flowering. Flea beetle injury ratings declined when 1) the high rate of insecticide seed treatment plus a foliar insecticide applied 21 d after planting was used, 2) the high rate of insecticide seed treatment only was used, or 3) two foliar insecticide sprays were applied. These insecticide strategies provided better protection than the low rates of insecticide seed treatments or a single foliar spray, especially in areas with moderate-to-high flea beetle populations. The foliar spray on top of the seed treatment controlled later-emerging flea beetles as the seed treatment residual was diminishing and the crop became vulnerable to feeding injury. The best insecticide strategy for management of flea beetle was the high rate of insecticide seed treatment plus a foliar insecticide applied at 21 d after planting, regardless of planting date.

Integrated Management of Haricot Bean Foliage Beetle in Northeastern Ethiopia

“…On the other hand, plots without Apron star seed dressing during normal planting date had the highest number of plants with damaged symptom and number of dead plants (112 and 65, respectively) ( Table 1; Figure 1). In agreement with our study, early planting coincides with peak beetle emergence and causes severe feeding activity [13][14][15]. To the contrary, late planting has low level of feeding injury [13][14][15].…”

“…In agreement with our study, early planting coincides with peak beetle emergence and causes severe feeding activity [13][14][15]. To the contrary, late planting has low level of feeding injury [13][14][15]. In addition, systemic seed treatment is the main strategy for the control of beetles and it provides protection for about three weeks after sowing [15].…”

Late flowering time enhances insect pollination of turnip rape

“…This may affect crop–pollinator interactions, similarly to those for wild plants and pollinators (Memmott et al., ; Petanidou et al., ). Shifting sowing date is also known as a cultural pest management strategy (Knodel, Olson, Hanson, & Henson, ; Lundin, Myrbeck, & Bommarco, ). A recent study proposed early sowing as a potential method to reduce flea beetle ( Phyllotreta spp.)…”

About Previous Investigations Regarding the Role of Glucosinolates in Controlling Brassica Insect Pests in Slovenia

“…The age of plants is among more important factors which influence the extent of damage by the species from the genus Phyllotreta. Authors [28] in their research report successful reduction of the extent of damage on cabbage done by the species from the genus Phyllotreta by different terms of seeding.…”