The Lexington dispatch. [volume] (Lexington, South Carolina) 1870-1917, 1912-05-29
The Iron and Braham Cow
peas Necessities Where
Wilt and Root Knot Occur

In all of the places visited III lhe
wilt infested sections of the State we
have found root|knot very prevalent.
I'm fact 70 t knot and cotton wilt seem
to 90 hand in hand. Where one occurs
the other is nearly always found. Eli
ther trouble is bad enough by itself,
but where they both occur they fire.
suently destroy whole crops of cotton
and cowpeas.
Root knot is caused by small mema-
todes (eel worms) which boro into the
roots of the plants and irritate the tis-
sne, causing enlargement of the points
attacked. These enlargemeots vary IN
sizs from almost nothing to the size Of
a pea and sometimes even larger.
When cut open and examined under
a microscope these knots are found to
be full of the tiny nematode worms.
These live oyer the winter in the old
roots and in the soil, and begin work
again the next spring in the young
roots. If the crops that they live on
are kept off the land for several years,
the nematodes are starved out.
We get rid of the root knot then by
rotation; i. e. we grow on the infested
land only those crops on which the
nematodes cannot live. Corn, oats,
wheat, rye. Iron-cowpeas, peanuts and
velvet beans are safe crops to use in
such rotation. Sweet potatoes, cotton,
eowpeas, tomatoes, okra, cucumoers,
watermelons, beans, tobacco, and a
number of other crops are subject to
root knot and are not safe to plant on
infested land.
Wilt is caused by parasitic fungus
which grows in through the roots of
the plants into the stems and plugs
ND the vessels which transport food
and water back and forth to the differ
ent parts of The plant. When these
vessels are clogged up the plant Wits
and dies. The fungus which causes
the trouble live in the soil and will re-
main alive for a number of years even
when cotton and peas are left off the
lands. The only way to control wilt
is by the use of ,sistant varieties, va
rieties which are almost wilt proof.
The varieties of cotton which are re-
sistant to wilt, however, are by no
means free from root knot encourages
wilt because the furg:s which causes
wilt easily enters the roots through
the wounds made by the nematode
worms. The first step then in con-
trolling witt is to get rid of the root
knot.
Now the culinary farm, practices
which are followed in this State tend
to encourage both wilt and root knot.
In the e 81 place. the wilt which at
sscks COTTON and rsas is practically
the tine, and the root knot which is
common on cotton, peas, potatoes and
tobacco is exactly the same. Oowpeas
which sre used in every imaginable ro-
tation are subject to both of those
which prove so disastrous to
cotton, so where we use the common
varieties of cowpeas in our rotation
we are enc ouraging both of these dis
eases. There are two varieties of cow
peas, hewever. which are free from
both root knot and wilt. These varieties
Rre the Iron and the Brabham; and it
Is with the view of calling attention
to these and emphasizing the necessity
for their more general use that this
article is written.
The South Carolina farmer cannot
farm without cowpeas, yet where wilt
and root knot occur he cannot grow
;he common varieties; and it is not safe
Tor him to plant them even where they
DO make some growth, because they
encourage the same disease of cotton. |