Host Plants - Westcott's Plant Disease - page 422

V IRUS D ISEASES - mosaics, ring spots, yellows,
wilt caused by viruses.
W HITE R USTS - white blisters in leaves.
W ILTS - systemic diseases, with wilting, death of
leaves, and branches.
W ITCHWEED - weed parasitic on roots.
The numbers given with the rusts refer to
spore stages. See under

a true mosaic disease, although fostered as
a desirable ornamental quality.

Acacia

C ANKER , Twig and Branch. Nectria ditissima,
CA, SC.
L EAF S POT . Physalospora fusca, FL; Cercospora
sp., GA; Phyllachora texana, TX.
L EAF S POT , Algal. Cephaleuros virescens, FL.
M ISTLETOE . Phoradendron californicum, CA,
TX; P. serotinum (flavescens), TX.
N EMATODE , Root Knot. Meloidogyne sp.
N ONPARASITIC . Chlorosis, due to excess lime, CA.
Gummosis, due to deficient or irregular mois-
ture, CA.
P OWDERY M ILDEW . Erysiphe polygoni, CA.
R OT , Heartwood. Ganoderma applanatum, CA.
R OT , Mushroom Root. Armillaria mellea, occa-
sional; Clitocybe tabescens, FL.
R OT , Root. Phymatotrichum omnivorum, TX.
R OT , Sapwood. Schizophyllum commune, CA.
R UST . Ravenelia australis,TX;R. gooddingii,AZ;
R. hieronymi, witches' broom, TX; R. igualica,
TX; R. roemerianae,TX;R. siliquae,NM,
TX; R. subtortuosae, witches' broom, TX;
R. thornberiana, witches' broom, AZ, TX;
R. versatilis, AZ, CA, NM, TX.

R USTS .

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Abelia

L EAF S POT . Cercospora abeliae, IL.
N EMATODE , Root Knot. Meloidogyne arenaria;
M. hapla; M. incognita.
N ONPARASITIC . Chlorosis, due to soil alkalinity,
TX.
P OWDERY M ILDEW . Oidium sp., TX.
R OT , Root. Phymatotrichum omnivorum, TX;
Rhizoctonia solani, TX; Pythium sp.
V IRUS . Abelia Latent, MD.

Abutilon (Flowering Maple, Indian
Mallow, Velvet Leaf)

B LIGHT , Foliage. Colletotrichum coccodes, VT.
B LIGHT ,

Phytophthora. Phytophthora

capsici, IL.
L EAF S POT . Alternaria sp., IL, IN, NJ, NY, TX;
Cercospora avicennae, MO, VA;
Cladosporium herbarum, KS, NY;
Colletotrichum malvarum,IA;Phyllosticta
althaeina, TX.
N EMATODE , Root Knot. Meloidogyne sp., AL, FL;
M. incognita,IN;M. hapla.
R OT , Root. Phymatotrichum omnivorum, TX;
Armillaria mellea, CA.
R OT , Stem. Macrophomina phaseoli, IL.
R UST . Puccinia heterospora (III), FL to AZ.
V IRUS . Abutilon Infectious Variegation; Abuti-
lon Yellows, CA; Bean Mosaic,HI;Mosaic,
universal.
W ILT . Verticillium albo-atrum, NJ; V. dahliae,
WI.
The leaf spots and rot occur on Indian mallow
and velvet leaf. Variegation in flowering maple is

Acacia (Koa Tree)

L EAF S POT , Brown; Dark Blight. Calonectria
colhounii, HI.

Acalypha (Copper-Leaf)

D OWNY M ILDEW . Plasmopara acalyphae, WI.
G ALL , Leaf. Synchytrium aureum, WI.
L EAF S POT . Cercospora acalyphae, NY to AL,
OK, TX, WI; Phyllosticta sp., NJ; Ramularia
acalyphae, TX.
N EMATODE , Lesion. Pratylenchus sp., FL.
N EMATODE , Root Knot. Meloidogyne sp., GA,

MD; M. incognita, IN.