Okolona messenger. (Okolona, Miss.) 1900-current, 1909-01-06

/ from bark of root; d, bright red perithecia
! from root OF dead plant; e. asci and ascos-
! pores borne in the peritnecia.
I that as a general rule the largeboll
sorts, Russell, Truitt, ETC., are more
subject to wilt than other groups Of
varieties. The most resistant of the
American Upland varieties tested was
the Jaskson Limbless, which produced
about 40 per cent of crop where
other kinds failed. The original Jack
son was not sufficiently resistant to
justify it's general cultivation, but 1t
has been of value as basis for breed
ing better races.
Egyptian cotton is more resistant to
wilt than Upland cotton, but 1t has
not as yet been found practicable to
utilize this quality, as the Egyptian
varieties do not succeed in our South
resistance direct from Upland varie-
ties than from crosses with Egyptian
cotton.
The individual differences in cotton
plants have been utilized as a basis
for breeding new resistant strains.
The work of the Bureau of Plant In
dustry has now been continued along
this line for eight years, and has re-
suited in the successful development
of two new varieties that can be
grown on the worst infected land, pro-
vided a rotation of crops for the con-,
troll of root-knot is practical.
The development of such varieties
however, is neither quickly nor easily
accomplished, but requires breeding
by exact methods for several years.
1t will not suffice to send pickers
through the fields to gather seed cot
ton from apparently resistant plants,
as some have recommended. Our ex-
perience has been that such mass Sc
lection Is expensive and ineffective.
Much of the seed obtained is taken
from plants not truly resistant, ana
the succeeding crop is nearly as much
diseased as the first. While such a
method should result in increasing
the resistance of the crop in the long
run, the cross pollination between re-
sistant and nonresident plants greatly
delays the results. The correct
method is to select with great care
a small number of plants that appear
to be healthy, though growing in the
worst infected areas. The seed from
each of these plants must be kept
separate and planted in parallel rows
on infected land the next year. The
resulting progeny will show which Of
the plants selected transmits the re-
sistant quality in the most effective
manner. The rows will also vary
much in productiveness and other
qualities. The best one should be Sc
lected and the other discarded. In'l
some cases aAresistant row of salts
factory quality has been found the
first year, and only two more sea-
sons were required to multiply the
seed, but more often complete success
has not been had at once and the
work had to be repeated
The origination of new wilt-resistant
varieties is work for the plant breeder
rather than the general farmer, and
there is need for men in every county
TO take up the business of breeding
to supply this demand The farmer,
however, should practice selection to
further improve, the strain purchased |
from breeders, or at least to preserve |
It from deterioration. The Bureau of
Plant Industry desires to stimulate
he breeding and sale of improved |
varieties of cotton To this end it will |
place the varieties already developed
N the hands of men who will improve
hem and offer them for SALE