Wilting means becoming flaccid. Wilting in plants may be temporary
Hue to too rapid evaporation but with a return to normal when water is
applied, or it may be permanent due to disease organisms interfering with
the water-conducting system. The pathogen need not be all through the
plant; it may be only in the roots or at the base of the stem, but by
either mechanical clogging or the production of a toxin it may produce
a response of the whole top or the yellowing, "flagging," of a single
BACTERIAL WILT OF CUCURBITS (Erwinia tracheiphila).
Serious on cucumbers and melons (cantaloupe but not watermelon), occasional on
squash. The bacteria winter in cucumber beetles and are inoculated into
the vines as beetles feed. Young plants are killed; older plants gradually
wilt and die. The bacteria form a viscous mass which oozes out from
Control. Keep beetles away by starting vines under Hotkaps or other
protection, then dusting with rotenone. Zerlate added to the dust helps to
control wilt. Pull and burn all diseased vines.
ASTER WILT (Fusarium oxysporum f. callistephi).
The fungus lives indefi-nitely in the soil and can be carried with the seed. Plants wilt,
wither, and die at any age from seedlings to full bloom. Older plants are
sometimes stunted with a one-sided development. If the affliction comes
when they are in bloom, heads suddenly droop.
Control. Nearly all seed stores carry resistant strains; be sure and ask
for them. The asters will not be completely immune, but you have a
chance of a good stand. There is no control by spraying.
CABBAGE YELLOWS (Fusarium oxysporum f. conglutinans).
This wilt disease is serious on cabbage and other crucifers in the Middle West
and is present in other sections. Plants are stunted, yellowish green; lower
leaves drop. The fungus can exist in the soil for many years, entering
through roots, usually soon after transplanting and with the first warm
Control. Once the fungus is established in the soil, you cannot get rid
of the disease by sanitation or spraying. Choose resistant varieties: Jersey
Queen, Resistant Detroit, Marion Market, Globe, Wisconsin Ball-head,
or Wisconsin All-Season.
DUTCH ELM DISEASE (Ceratostomella ulmt).
This fatal wilt disease of
American and European elms first appeared here in 1930 and is
now present from Massachusetts to Virginia and West Virginia and is
known in Ohio, Indiana, and Colorado. Many towns have lost a large
proportion of their elms, but those communities which have continuously
practiced a strict sanitation program have saved most of their trees.