Host Plants - Westcott's Plant Disease - page 574

N EMATODE , Lesion. Pratylenchus pratensis, OH,
WA.
R OT , Basal. Fusarium oxysporum f. sp. narcissi,
general on hardy varieties.
R OT , Black Bulb. Sclerotinia sclerotiorum;
crown; wet scale,

B LIGHT , Gray Mold. Botrytis cinerea, AK.
D ODDER . Cuscuta sp., MO, NH.
L EAF S POT . Cercospora tropaeoli, AL;
Heterosporium tropaeoli, CA, NY;

Pleospora sp., MS, NJ, OH.
N EMATODE , Root Knot. Meloidogyne spp., NJ,
TX; Heterodera schachtii, root gall.
R UST . Puccinia aristidae (0, I), UT; II, III on
grasses.
V IRUS . Beet Curly Top, CA, TX; Tomato Spot-
ted Wilt, CA, MD, TX.
Compared with the almost inevitable affliction

Sclerotium rolfsii, CA,

FL, NY, VA.
R OT , Large Scale Speck. Stromatinia narcissi,
general in northern bulb areas.
R OT , Leaf and Stem. Gloeosporium sp., LA, NC.
R OT , Neck; Smoulder. Sclerotinia narcissicola,
NJ, NY, OR, VA, WA; probably general
except on polyanthus varieties.
R OT , Root and Bulb. Armillaria mellea, CA, OR,
WA; Aspergillus spp., black mold; Penicil-
lium spp., blue mold, in wounds;
Trichoderma viride, green mold in scales,
cosmopolitan after sunscald; Rhizopus
stolonifer, soft rot, cosmopolitan after sun-
scald; Cylindrocarpon radicicola, secondary
root rot.
R OT , Small Scale Speck; Neck Rot. Sclerotium
sp., general, especially in southern bulb
districts.
V IRUS . Narcissus Mosaic, mild; Narcissus
Flower Streak; Narcissus Chocolate Spot;
Narcissus Yellow Stripe, Gray Disease,
often called Mosaic, general; White Streak,
general.
Control of narcissus diseases rests with the
grower, who should, and usually does, supply
the gardener with sound, healthy bulbs. Inspect
all bulbs carefully before planting, making sure
there are no dark sclerotia on the scales or the
chocolate brown of Fusarium rot at the base. The
bulb and stem nematode is controlled by treating
in hot water.

of black aphids, nasturtium diseases are

insignificant.

Nectarine (Prunus persica var.
nectarina)

B ACTERIAL Canker. Pseudomonas syringae, CA.
B ACTERIAL Crown Gall. Agrobacterium

tumefaciens,MO.
B ACTERIAL Leaf Spot; Canker. Xanthomonas
pruni, OK.
B ACTERIAL , MLO. Peach X-Disease.
C ANKER . Valsa leucostoma, DC.
L EAF C URL . Taphrina deformans, CA, OR, TX,
WA.
L EAF S POT . Cristulariella pyramidalis, FL.
L EAF S POT ; Shot Hole. Coryneum carpophilum,
CA, OR, WA.
N EMATODE , Lesion. Pratylenchus thornei, CA.
N EMATODE , Root Knot. Meloidogyne sp., CA;
usually resistant.
P OWDERY M ILDEW . Podosphaera oxyacanthae,
ID, WA; Sphaerotheca pannosa, ID, NY,
WA.
R OT , Brown; Twig Blight. Monilinia laxa, CA,
WA; M. fructicola, CT, NY, TX.
R OT , Pink Mold. Trichothecium roseum, CA.
R OT , Sour. Geotrichum candidum, CA;
Issatchenkia scutulata, CA; Kloeckera
apiculata, CA.
S CAB . Cladosporium carpophilum, CT, DE, IL,
NY, PA, TX.
V IRUS . Peach Mosaic; Peach Yellows; Peach
Latent Mosaic Viroid,WA;Hop Stunt
Viroid, Ontario, Canada.

Nasturtium (Tropaeolum)

B ACTERIAL Fasciation. Clavibacter fascians, CA.
B ACTERIAL Leaf Spot. Pseudomonas syringae
pv. aptata, ME, MN, MS, NJ, PA, VA.
B ACTERIAL , MLO. California Aster Yellows,
CA.
B ACTERIAL Wilt. Pseudomonas solanacearum,
FL, MD, NJ, NC, VA.