Agriculture Reference
In-Depth Information
allii-cepae
on
foliage
5.0-8.5°C
optimal, old
chlorothalonil
prevent spore
starts, also on
onion and others,
L, gh (
C. allii
)
bleaching,
after 8 h dark,
and senescent
or fentin
spread at
overwintering
C. allii
on leeks
Te
olive/brown
RH > 90%,
leaves and
acetate every
harvest,
crops in UK
(see Plate 2)
sporing patches
low light
leaf tips
14 days late
rotation
in season
> 2-3years
Twister, seven
O and many
Twisted, curled
Debris,
23-30°C, high
Zineb, ferbam,
Hygiene
Insects and
curls, anthracnose,
hosts
leaves,
alternate
RH, rain-
captan, dithane
irrigation water
Glomerella cingulata
chlorosis,
hosts, seeds
splash and
or copper
can spread spores
St, tr
long necks,
wind-spread
formulations
white lesions,
infection
pink spores
O, g, l
4
Powdery mildew,
5-15 mm yellow,
Infects via
Rare, infects cvs
lacking leaf wax
5
Leveillula taurica
circular
stomata,
Te, st
lesions on
particularly
leaves forming
on older leaves
powdery conidia
Downy mildew
b
,
O, s, g, j, c
Pale, elongated
Debris, crop
3-25°C,
Optimum
Dithiocarbamates, Cv. differences
Avoid crop
Heat-treat infected
Peronospora
patches on
overlap,
100% RH,
10-12°C,
copper,
reported,
overlap, hygiene,
bulbs for 4 h at
destructor
Te
leaves forming
volunteers,
spores form
free water
chlorothalonil.
resistance from
rotation > 4
41°C, forecasting
(see Plates 2
grey/purple
systemically
at night and
on leaf for
Fosetyl-Al,
A. roylei
being
years; to
models developed
and 6C)
felt of sporing
infected bulbs
release with
2-4 h
metalaxyl,
transferred to
minimize RH
bodies, chlorosis or sets
RH drop in
alternate
onion (see
round leaves,
and collapse of
day, 9-16 days
different
Chapter 3)
use wide
leaves and
latent period
fungicides to
spacing, orient
flower stalks
between
avoid pathogen
rows parallel
infection and
resistance
to prevailing
spore production
wind and use
moderate N
