Agriculture Reference
In-Depth Information
narrow strips of tissue between the veins; dam-
aged areas appear whitish. Leaf symptoms are
similar to those produced by cereal leaf beetles,
Oulema
spp. (p. 144
et seq.)
but the stripes are
much narrower and usually far less extensive.
Barley flea beetles also feed on beet and brassica
crops, such as cabbage, radish and turnip; they
cause typical flea-beetle injury that, on seedlings
in the spring, may be of some significance (see
under
Phyllotreta cruciferae,
p. 146); the larvae
also feed in the stems.
and turnip. The life-cycle and habits are similar
to those
of Phyllotreta cruciferae
(p. 146). Adults
are 2.0-2.5 mm long and black, with elongate,
strongly punctured elytra; the antennae are
mainly black, with the second and third segments
reddish-brown. In the British Isles, this pest is
particularly common in eastern England.
Phyllotreta consobrina
(Curtis)
A turnip flea beetle
This southerly distributed but local species
is 1.8-2.0 mm long, oval-bodied and black with a
bronzy or bluish sheen; the elytra are moderately
punctured, and the legs and antennae are
entirely black (cf.
Phyllotreta nigripes,
below).
The life-cycle and habits are similar to those of
P. cruciferae
(p. 146).
BIOLOGY
Adults become active in the spring, from March
or April onwards. They often occur in associa-
tion with brassica plants and also invade grasses
and cereals. Eggs are laid in May and June. The
larvae feed within the stems of brassicas and
various other plants, eventually pupating in the
soil. New adults appear in July or August. They
feed briefly before seeking overwintering sites
amongst debris on the ground.
Phyllotreta diademata
Foudras
Crown flea beetle
This widely distributed species is small (1.8-
2.0mm long) and mainly black, with strongly
punctured elytra and the first three or four
antennal segments reddish-brown. The biology
and habits are similar to those of
Phyllotreta
cruciferae
(p. 146).
DESCRIPTION
Adult
1.5-1.8mm long, black with a wide longi-
tudinal, yellow stripe along each elytron; distin-
guished from
Phyllotreta nemorum
(p. 147) by
the smaller size, the narrower, straighter elytral
band, the more parallel-sided elytra and mainly
black tibiae.
Larva
up to 4mm long;
body
whit-
ish and relatively slender;
head
blackish;
anal
segment
with a minute tail-like peg (pseudopod).
Phyllotreta nigripes
(F.)
This flea beetle is more abundant in southerly
areas and appears somewhat earlier in the spring
than other related species. Adults are 2.0-2.5 mm
long, and black with a metallic blue or metallic
green sheen and very finely punctured elytra (cf.
Phyllotreta consobrina,
above); the antennae are
entirely black; the legs are black with brownish
tibiae. Larvae are mainly white with reduced
thoracic and abdominal plates. Adults feed on
various members of the Brassicaceae, and larvae
attack the roots of such plants.
Phyllotreta aerea
Allard
Small black flea beetle
This southerly distributed flea beetle is 1.5-
1.8 mm long and mainly black, with the elytra
moderately but closely punctured, and the
second and third antennal segments reddish-
brown. The life-cycle and habits are similar to
those of
Phyllotreta cruciferae
(p. 146).
Phyllotreta atra
(F.)
A turnip flea beetle
Phyllotreta undulata
Kutschera
Small striped flea beetle
The small striped flea beetle is often an abundant
pest of Brassicaceae, including watercress and
This species is a generally abundant pest of veg-
etable brassica crops, including cabbage, radish
