Host Plants - Westcott's Plant Disease - page 591

R OT , Root and Pod. Sclerotinia minor,
S. sclerotiorum, NC, VA; Sclerotium rolfsii,
FL; Sclerotinia sclerotiorum, GA.
R OT , Seed. Rhizopus spp.; Trichoderma viride,
SC.
R OT , Stem, Pod. Fusarium spp., also root rot,
wilt; Physalospora rhodina, FL, GA; Rhi-
zoctonia solani; Sclerotium rolfsii, FL;
Sclerotinia

N. galligena, trunk canker; Nummularia
discreta, DE, IA.
C ANKER , Bark. Glutinium microsporum, OR;
Helminthosporium papulosum, blister can-
ker, black pox; Myxosporium corticola,NY
to MI, MS, OR.
C ANKER , Felt Fungus. Septobasidium spp., NC to
FL, TX.
C ANKER , Perennial. Neofabraea perennans, OR,
WA.
D ECLINE , Pear. Candidatus Phytoplasma pyri,
Ontario, Canada.
F RUIT S POT ; Flyspeck. Leptothyrium pomi, east-
ern states.
L EAF S POT . Cercospora minima, FL to TX;
C. pyri, MI; Coniothyrium pyrinum,MA
to AL, IA, TX; Coryneum foliicola, IN;
Hendersonia cydoniae, NY; Phyllosticta
pyrorum, IL, MS, SC; Mycosphaerella
sentina, ashy leaf spot, fruit spot, widespread,
especially in East.
M ISTLETOE .

sclerotiorum, GA, NM;

S. minor, TX.
R UST . Puccinia arachidis (II), occasional, FL,
GA, NC, TX, VA.
V IRUS . Peanut Stunt, AL, FL, GA, NC, VA;
Peanut Mottle, GA, OK; Cowpea Chlorotic
Mottle, SD; Peanut Stripe, GA; Zuccinia
Yellow Mosaic, GA; Impatiens Necrotic
Spot, GA, TX; Peanut Top Paralysis, OK;
Tomato Spotted Wilt, AL, GA, VA, TX;
Peanut Chlorotic Ringspot, GA.
W ILT . Pythium myriotylum, VA; Verticillium
sp., NM.

Phoradendron serotinum

(flavescens), AZ, TX.
M ISTLETOE , European. Viscum album, CA.
N EMATODE , Lesion. Pratylenchus minyus;
P. pratensis, CA.
N EMATODE , Root Knot. Meloidogyne sp., CA.
N ONPARASITIC . Bitter Pit. Moisture irregularity,
Pacific Coast, NY.
Black End; Hard End. Oriental pear rootstocks
on shallow, poor soil.
Black Leaf; Brown Bark Spot; Brown Blotch,
of Kieffer fruit. Undetermined.
Chlorosis. Mineral deficiency, soil alkalinity,
Pacific Coast.
Cork; Drought Spot; Fruit Pitting. Boron defi-
ciency, Pacific Coast, TX.
Exanthema. Copper deficiency, CA, FL.
Little Leaf; Rosette. Zinc deficiency, sometimes
boron, CA.
Marginal Leaf Blight; Scorch. Potassium or cal-
cium deficiency, ID, WA.
Red Leaf. In Oriental pear, undetermined cause.
Scald. Immaturity; deficient ventilation.
Stigmonose. Insect punctures during growth,
widespread.
Target Canker, Measles. Undetermined, CA,
GA, NY, VA, WA.

Pear (Pyrus)

A NTHRACNOSE , Northwestern. Neofabraea

malicorticis, OR, WA.
B ACTERIAL Blossom, Twig Blight; Canker. Pseu-
domonas syringae, AR, CA, CT.
B ACTERIAL Crown Gall. Agrobacterium

tumefaciens, general.
B ACTERIAL Fire Blight. Erwinia amylovora,
general.
B ACTERIAL Fruit Rot. Erwinia carotovora,MA.
B LIGHT , Leaf; Black Fruit Spot. Fabraea
maculata, general.
B LIGHT , Thread. Pellicularia koleroga,NCto
FL, TX, WV.
B LIGHT , Twig. Corticium salmonicolor, FL, LA;
Fusarium spp., occasional; Phomopsis
ambigua, widespread; Valsa leucostoma,
WA.
B LOTCH , Sooty. Gloeodes pomigena, eastern
states to OK, TX.
C ANKER . Botryosphaeria dothidea, AL;
Cytospora spp., OR, VA, WA; Nectria
cinnabarina, coral spot; dieback;