Phenology and suppression of stem weevils (Ceutorhynchus napi gyllenhal and Ceutorhynchus pallidactylus marsham) in oilseed rape in northern Serbia
Stem weevils (Ceutorhynchus pallidactylus and Ceutorhynchus napi) are significant pests of oilseed rape that farmers regularly suppress by insecticide treatments intended against Brassicogethes aeneus. Recent studies have shown that in some regions of northern Serbia C. napi is dominant, while C. pa...
Saved in:
Published in | Pesticidi i Fitomedicina Vol. 33; no. 3-4; pp. 213 - 220 |
---|---|
Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Institute of Pesticides and Environmental Protection
2018
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Stem weevils (Ceutorhynchus pallidactylus and Ceutorhynchus napi) are
significant pests of oilseed rape that farmers regularly suppress by
insecticide treatments intended against Brassicogethes aeneus. Recent
studies have shown that in some regions of northern Serbia C. napi is
dominant, while C. pallidactylus prevails in others. Increased damage from
stem weevils has elicited an exploration of the situation and a study of
their phenology and effects of insecticides in three differently managed
fields: conventional, organic and integrated. New findings regarding the
phenology of stem weevils show that both species were sporadically present
in our experimental oilseed rape fields as early as during autumn (from the
end of October 2010, BBCH 17-18). The main period of stem weevil settlement
is the end of winter and early spring. Maximum flight of both weevil species
was recorded on March 23 at the beginning of oilseed rape (OSR) stem
elongation (BBCH 22-25), and one week later in the organic field. There were
no significant differences in the number of settled weevils among the three
differently managed fields. The insecticide treatment against C. napi was
applied two weeks earlier than the usual treatment against B. aeneus and C.
pallidactylus. Thus, it is clear that insecticide treatment directed against
B. aeneus and C. pallidactylus is not effective against C. napi. In this
way, such a practice can contribute to an increase in OSR damage, and
density of the next generation of C. napi. A new generation of C.
pallidactylus emerged from OSR fields in June 2011, while the majority of C.
napi emerged in March of the following year. |
---|---|
ISSN: | 1820-3949 2406-1026 |
DOI: | 10.2298/PIF1804213S |