The Grangeville globe. [volume] (Grangeville, Idaho) 1907-1922, 1921-09-29

DO big seed pieces produce better
potatoes than small pieces?
When does the tuber begin to form?
When does moisture have the most
effect on The production OF potatoes?
What Is the relation of soil to DO
tatc production?
Experiments Conducted.
These are few among many ques
u9nS which have been asked about thu
growth ana yield Of Americas largest
and most distinctive crop and which
former observers have been able 20
answer only incompletely. The bu-
reau Of plant industry, United States
department OF agriculture. has con-
Quoted series Of experiments in pr
lato growth, the results of which are
published in department bulletin 95S.
development of tubers in the potato,
which has just been issued. The in
formation contained is of interest not
only TO the plant Psychologist but ais
to the practical grower as a knowledge
of the relation Of the setting and sub
segment development of tubers of the
potato may, to a certain extent, be put
to practical use.
Tuber formation, ii was found, be
gins in general at about the end of tn.
period of flower bud development, al
though this is not il all cases an exact
criterion. Experiments showed that
the number as well as the size of po-
tatoes in hill increased for several
weeks after the first potatoes were
large enough to dig small increase
in the weight Of tubers was found tn
occur even after the vines had been
killed by frost. The maximum rate
Of growth of the tubers was found to
occur about the last of August or first
Of September, which was approximate
ly so days after planting.
An interesting development Of the
experiments was that the number and
weight of tubers per hill were found
to be influenced by the size and kind
of seed planted. Whole potatoes used
as seed yielded heavier than half DO
tatoes and these more than quarters,
and the larger the seed piece the
greater the yield per hill A whole
potato used as seed yielded more than
a half or quarter potato OF equal
weight
The experiments showed that APP
parently light soils are better for po-
tatoes than heavy soils. The lowest
production of tubers, with respect to
both number and weight per hill, was
on the heaviest soil; the highest mum
bers and yields were produced on the
lightest soil. The department thinks
it possible. however. that these results
might be modified somewhat under
different climatic conditions.
Resulted i'm Increase.
Two-year tests with irrigation indl-
cate that the early application of wa.
ter before tuber formation had started
resulted in an increase in the number
of tubers as well as in the weight PEI
hill Late irrigation actually increased
the weight but made little difference
in the number Of tubers per hill. The
irrigation experiments were not carried
to final conclusion. but indicate that
each application of water at aImos.
any period in the growth of the plant,
provided excessive quantities are not
used, may be expected TO produce an
increase in the weight Of the crop, but
that little or no increase in the num-
Der of tubers is likely to result from
irrigation after INSTRUMENTATION is well
started.
The bulletin contains an interesting
description of the tuber-b hearing parts
Of potatoes and their method Of
growth 1t may he obtained free on
request to the division Of publications.
United States department of agricul-
ture.