Hayes and Garber - Cucurbit Breeding

FIELD PLOT TECHNIC 61
size of plot is necessarily limited by available space and sometimes
by amount of seed. Some form of row planting is usually
followed. These rows are planted, cultivated, and harvested
by hand and frequently show as low probable errors as those
obtained from ^o~acre field plots.
11
10
^ 9
g 8
H 7
!.
I 5
5 4
11 A.
500250 125 *
i- Size of Plot
FIG. 13. Actual and theoretical reduction in standard deviation due to increase
in size of plot.
Shape of Plot and Border Effect. Often plants growing along
the side or end of the plot are more thrifty and vigorous than
those growing in the interior. When plots consist of single rows,
the plants at the extremities near the alleys or pathways appear
superior to those growing farther in.
Mercer and Hall (1911) cut up a bulk field into plots of equal
area but different in shape (approximately 20 by 12 yd. and 50 by
5 yd.) and therefore without border effect. No significant difference
in comparative variability was found between the two
shapes. Barber (1914) found that where cultivated pathways
surrounded plots, the plants along the margins were more productive
than those within the plot.
Table XIII presents data collected by Arny and Hayes (1918).
The plots were seeded with a grain drill, the drill rows being 6 in.
apart. Eighteen-inch alleys separated the plots, and there was
a roadway along each end. In length the plots were trimmed
to 132 feet. In breadth they were 17 drill rows, each 6 inches
apart. Each of the two outside border rows was harvested separately
and the yield compared with the yields obtained from the