Glucosinolate profile and oviposition behavior in relation to the susceptibilities of Brassicaceae to the cabbage seedpod weevil

Abstract

Understanding how host‐plant characteristics affect behavioral and physiological responses of insect herbivores is of considerable importance in the development of resistant crop germplasm. Feeding, oviposition preference, larval development, and oviposition behavior of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (= Ceutorhynchus assimilis Payk.) (Coleoptera: Curculionidae), were investigated on eight Brassicaceae species that differed in their glucosinolate profiles. The least preferred host plants for feeding and oviposition were the Sinapis alba L. lines while the Brassica carinata L. line was most preferred. Larval development occurred most rapidly on Brassica rapa L. and slowest on S. alba. Larval weight was highest on B. napus L. and lowest on S. alba. Total glucosinolate levels did not influence C. obstrictus larval growth or development; however high levels of specific glucosinolates such as p‐hydroxybenzyl and 3‐butenyl glucosinolate were associated with increased developmental time or reduced weight. The time required for oviposition behavioral events was measured on different host‐plant species: B. rapa, B. napus, B. napus×S. alba, B. tournefortii Gouan., B. juncea (L.) Czern, B. carinata, B. nigra (L.) Koch., and S. alba. The early steps in the sequence were completed faster on more susceptible host plants (B. carinata, B. napus, and B. rapa) than on relatively resistant ones (B. tournefortii and B. juncea). Females explored pods of B. nigra and S. alba, but oviposition occurred only rarely on these species. There was no significant difference in the location on the pod on which oviposition occurred among the different plant species. Mean eggs laid per female weevil were highest on the B. napus×S. alba hybrid and lowest on B. nigra and S. alba.

Biochemical markers for cabbage seedpod weevil (Ceutorhynchus obstrictus (Marsham)) resistance in canola (Brassica napus L.)

“…Other research showed that Brassicaceae plants with high amounts of 3-BT had high levels of weevil oviposition (Moyes and Raybould 2001), whereas the plants with 2-propenylglucosinolate (2-PG) in the seed had significantly fewer weevil attacks. Specific glucosinolates appear to have influence on acceptance or rejection as potential hosts in B. napus by the weevil, while total glucosinolates do not influence CSPW resistance (Ulmer and Dosdall 2006). The presence of this unknown glucosinolate in the Stage 3 seed appears to influence larval development and may be associated with missing larval nutritional needs.…”

“…Therefore, it is assumed that the CSPW responds to different canola plants in varying degrees based on the endogenous glucosinolate complement. Some literature suggests that p-hydroxybenzyl and 3-butenylglucosinolates (3-BT) may affect larval development, while other researchers identify certain polyphenols, flavonoids or other chemical and volatile compounds that may cause preferences by the CSPW to favor certain cultivars of B. napus (McCaffrey et al 1999;Ulmer and Dosdall 2006).…”

Defence mechanisms of Brassicaceae: implications for plant-insect interactions and potential for integrated pest management. A review

“…The cabbage seed weevil invades oilseed rape crops, the adults colonise flowering host plants and feed on pollen, and the larvae feed on the developing seeds before leaving the pods and pupating in the soil. The cabbage seedpod weevil (C. obstrictus) is native to Europe, and is a serious pest of brassicaceous oilseed crops in Europe and North America (Bartlet et al, 1993;Ferguson et al, 1999b;Ulmer and Dosdall, 2006;Valantin-Morison et al, 2007). The cabbage seedpod weevil is a small, dark grey "snout beetle" normally occurring after peak flowering and lays eggs in the pods of cruciferous plants.…”

“…With this hypothesis, Ulmer and Dosdall (2006) investigated feeding, oviposition preference, larval development and oviposition behaviour of the cabbage seedpod weevil (C. obstrictus) on eight Brassicaceae species that differ in their glucosinolate profiles. Among these eight Brassica species, the preferred host plant for feeding and oviposition was B. carinata, larval development occurred most rapidly on B. rapa, and the larval weight was highest on B. napus.…”

Bottom-up effects of Brassica napus nutrition on the oviposition preference and larval performance of Ceutorhynchus obstrictus (Coleoptera: Curculionidae)

“…The experimental design was based on the choice experiments performed by Harmon and McCaffrey (1997) and Ulmer and Dosdall (2006b). A closed arena, with a volume of 2,166 cm 3 (19 cm long 9 19 cm wide 9 6 cm high), was used to enclose eight rows and eight columns of excised pods.…”