- An investigation of the effects of soil and foliar applications
of boron and of time of foliar application of boron on
growth, yield, and boron content of bush snap beans was made
during the 1962 growing season. This study was conducted at two
locations: Corvallis and Aurora, Oregon.
Yield, dry weight, and boron content were computed on the
individual plot basis, and results were statistically analyzed.
Data were also collected on sieve size distribution of pods and
percent pod set. Rates of zero, one, and two pounds of boron per
acre were applied to the soil, and the foliar rates consisted of
0, 10, 50, 100, 250, 500, and 1,000 ppm boron.
Applications of boron to the soil in general resulted in a
slight decrease in yield of snap beans. Foliar applications of
boron followed an erratic pattern, slightly increasing yield in
one location and decreasing it at the other. Foliar rates of
250 and 500 ppm boron applied under a combined early-late foliar
application resulted in the largest decrease in yield of snap
beans, although the effects of boron applications were, not
Boron applications decreased the. dry weight of the above-ground
portion of bean plants at one location and increased dry
weights at the other. However, boron applications did not significantly
affect dry weight of snap beans.
Soil applied boron produced a statistically significant
increase in boron content of bean plants, irrespective of the time
of sampling. An earlier sampling made prior to bloom showed that
boron content of bean plants was higher at this stage of growth
than at full bloom. Foliar applications of boron consistently
increased boron content of bean plants. Boron content of plants
at bloom ranged from approximately 22 to 50 ppm at Corvallis and
from 20 to 35 at Aurora.
Because no toxic effects were observed as a result of boron
applications to the soil, it is believed that the soil boron rates
used in this experiment were within the range of tolerance, of snap
beans to boron. No toxicity effects due to foliar applications of
boron were observed when rates below 250 ppm boron were applied.
Neither percent pod set nor sieve size distribution were
significantly affected by the boron levels used in this experiment.
The relationship of the results of this study to reports of other
work is discussed.