Biology Reference
In-Depth Information
no exudate. Bacteria enter through stomata and
fill intercellular spaces of parenchyma.
Burkholderia caryophylli formerly
Pseudomo-
nas caryophylli
).
Bacterial Wilt
of carnation, usu-
ally under glass. Plants wilt, turn dry, colorless
with roots disintegrating. Grayish-green foliage
is the first symptom, but leaves rapidly turn
yellow and die. Yellow streaks of frayed tissue
in vascular areas extend a foot or two up the stem.
It takes a month for disease to show up after
inoculation, but it can be transmitted on cuttings
taken from plants before appearance of symp-
toms. The sticky character of diseased tissue dis-
tinguishes this wilt from Fusarium wilt. Varieties
Cardinal Sim, Laddie, Mamie, Portrait, and
others may have severe cankers at base of
stems, orange-yellow when young, very sticky.
Bacteria are spread by hands, tools, splashing
water. Also causes crown and leaf rot of statice.
Control
Remove and burn diseased plants and
all within 1 1/2 -foot radius. After handling wash
with hot water and soap, sterilize tools (10 %
Clorox for 5 min). Obtain rooted cuttings from
propagators of cultured, disease-free material;
keep in shipping bags until ready for benching
and then place in raised, steam-pasteurized
benches. Never place cuttings in water or
a liquid fungicide (use dust if a fungicide is
required for other diseases); never place tempo-
rarily on an unsterilized table; never cut or trim
with hands or knives; never plant in outdoor
“nurse beds”; never use overhead watering.
Burkholderia cepacia (formerly
Pseudomonas
cepacia
).
Sour Skin Rot
of onion. Slimy yellow
rot of outer fleshy scales, with a vinegar odor. Let
crop mature well before harvesting, tops dry
before topping; cure bulbs thoroughly before
storage.
Burkholderia gladioli (formerly
Pseudomonas
gladioli
).
Leaf Spot
and
Blight
on bird's nest fern.
Onion Bulb Rot
, a storage disease, inner scales
of bulb water-soaked and soft, sometimes entire
bulb rotting.
Orchid Brown Rot
and
Leaf Spot
.
Gladiolus Scab
,
Stem Rot
,
Neck Rot
, wide-
spread on gladiolus, also on iris, bell peppers and
tigridia. Lesions on corms are pale yellow, water-
soaked circular spots deepening to brown or
nearly black, eventually sunken with raised,
horny, or brittle margins that are scablike and
exude a gummy substance. Bacteria overwinter
on corms. First symptoms after planting are tiny
reddish raised specks on leaves, mostly near the
base, enlarging to dark sunken spots, which grow
together into large areas with a firm or soft rot.
Sometimes plants fall over, but the disease is not
ordinarily very damaging in the garden. The chief
loss is to the grower in disfigured, unsalable
corms. Brown streaks in husks sometimes disin-
tegrate, leaving holes.
Gladiolus scab is increased by bulb mites, may
be related to grub and wireworm injury.
Pseudomonas aceris (see
Pseudomonas
syringae
pv.
aceris
).
Maple Leaf Spot
found in
California on big leaf maple.
Pseudomonas adzukicola
Stem Rot
of adzuki
bean.
Pseudomonas albopreciptans (see
Acidovorax
avenae
).
Bacterial Spot
of cereals, grasses, and
corn.
Pseudomonas and ropogonis (see
Burkholderia and ropogonis
).
Bacterial Stripe
of sorghum and corn.
Bacterial Leaf Spot
of velvet bean, clovers.
Translucent angular brown leaf spots have lighter
centers and chlorotic surrounding tissue; there is
no exudate. Bacteria enter through stomata and
fill intercellular spaces of parenchyma.
Pseudomonas angulata (see
Pseudomonas
syringae
pv.
angulata
).
Blackfire
of tobacco.
Pseudomonas asplenii
Bacterial Leaf Blight
of
bird's-next fern, first reported from greenhouses
in California. Small translucent spots enlarge to
cover whole frond; bacteria may invade crown
and kill whole plant. Control depends on strict
sanitation - sterilizing flats, pots, media, and
foreceps used in transplanting. Avoid excessive
watering and too high humidity.
Pseudomonas avenae (see
Acidovorax avenae
).
Bacterial Leaf Spot
of sweet corn.
Bacterial Leaf
Blight
of johnsongrass.
Pseudomonas berberidis
Bacterial Leaf Spot
of barberry. Small, irregular, dark green water-
soaked areas on leaves turn purple-brown with
age; occasional spotting occurs on leaf stalks and
young shoots. If twigs are infected, buds do not
