Host Plants - Westcott's Plant Disease - page 488

M OLD . Seed. Alternaria tenuis, cosmopolitan;
Curvularia trifolii, NJ.
N EMATODE , Hop Cyst. Heterodera humuli, OR.
N EMATODE , Root Knot. Meloidogyne incognita;
M. javanica.
N ONPARASITIC . Chlorosis. Nitrogen, manganese,
or potassium deficiency.
P OWDERY M ILDEW . Golovinomyces
cichoracearum, general; Sphaerotheca
fuliginea, CA, NC; Leveillula taurica, ID.
R OT , Charcoal. Macrophomina phaseoli, IL.
R OT , Fruit. Fusarium spp., TX; Rhizopus
stolonifer, occasional. Diplodia natalensis;
Botrytis cinerea.
R OT , Root. Fusarium solani f. sp. radicicola,
CT, OR, WA; Phymatotrichum omnivorum,
TX.
R OT , Stem; Fruit. Sclerotinia sclerotiorum,
occasional.
S CAB . Cladosporium cucumerinum, general.
V IRUS . Bromegrass Mosaic Virus, general;
Cucumber Mosaic, general; Beet Curly
Top, CA, ID, OR, TX, UT, WA; Tobacco
Ring Spot, MD, PA, VA; Zucchini Yellow
Mosaic, CA, FL, NY; Cucurbit Leaf Curl,
AZ, NM, TX.
W ILT . Fusarium oxysporum f. sp.
cucumerinum, FL; F. oxysporum f. sp.
cucurbitae; Verticillium albo-atrum, CA.
W ILT , Basal Stem Lesions. Phytophthora
capsici, Mexico.
Starting cucumbers under Hotkaps and then
treating to control insect vectors helps to reduce
bacterial wilt and virus diseases. Choose varieties
resistant to mosaic and scab.

Cryptanthus

A NTHRACNOSE . Gloeosporium sp., WA.

Cryptomeria

B LIGHT , Leaf and Twig. Diaporthe eres;
Phyllosticta cryptomeriae, VA and general
U.S.
L EAF S POT . Pestalotia cryptomeriae, SC;

P. funerea, NJ.

Cucumber (Cucumis sativus)

A NTHRACNOSE . Colletotrichem lagenarium,
general.
B ACTERIAL Angular Leaf Spot. Pseudomonas
syringae pv. lachrymans, general.
B ACTERIAL

Soft Rot. Erwinia aroideae;

E. carotovorus.
B ACTERIAL Spot. Xanthomonas cucurbitae, MA,
MI.
B ACTERIAL Wilt. Erwinia tracheiphila, general.
B LIGHT , Blossom; Fruit Rot. Choanephora
cucurbitarum, FL, GA, NJ, OK, RI, TX.
B LIGHT , Gummy Stem; Black Fruit Rot.
Mycosphaerella

citrullina, widespread;

M. melonis, AZ.
B LIGHT , Leaf. Alternaria cucumerina, general.
B LIGHT , Southern. Sclerotium rolfsii, VA to FL,
TX.
D AMPING -O FF . Rhizoctonia solani, also stem rot;
Pythium spp.
D ODDER . Cuscuta gronovii, NY.
D OWNY M ILDEW . Pseudoperonospora cubensis,
general; U.S., Beirut, Lebanon.
L EAF S POT . Cercospora cucurbitae AL, DE, IA,
NJ, TX, WI; Ascochyta sp., OR; Gloeosporium
sp. IL; Phyllosticta cucurbitacearum,DE,OH,
TX; Septoria cucurbitacearum,DE,MA,NH,
PA; Stemphylium cucurbitacearum, OH;
Alternaria consortiale,WA;Ulocladium
cucurbitae, CA, NY.

Culvers-Root (Veronicastrum)

L EAF S POT . Cercospora leptandrae, WI;
Phyllosticta decidua, TX, WI; Ramularia
veronicae, TX; Septoria veronicae, WI.
P OWDERY M ILDEW . Golovinomyces
cichoracearum, IL; Sphaerotheca
macularis, CT, IL, IA, MD, MI, MO, WI.
R OT , Root. Phymatotrichum omnivorum, TX;
Rhizoctonia solani, TX.
R UST . Puccinia veronicarum (III), IA, TX, WI.