International Journal of Horticulture, 2017, Vol.7, No. 12, 95-105
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Figure 1 Individual growth curve of yam
Note: Longitudinal growth curves of 60 yam plants and the overall mean response curve of yam yield are shown in Figure 1. The
curves, in general, have upward tendency. This tendency is more prominent for the seed weight 800 g., indicating that with nominal
care for yam plants in an extremely harsh environment of cultivation at Giridih, a higher seed weight like 800 g is more appropriate
for more yield. A downward trend is sometimes observed from the time of second interim reading, especially when yam detachment
is made at the time of first interim reading. Figure 1 seems congested with many growth curves
Figure 2 Individual growth of yam for seed wt. 500 gm
Note: We examine the curves for seed weight 500 g separately. Initial downward trend of the curves due to nominal care of plants is
countered under the stimulus of uprooting the plants during first interim reading, as is apparent from the first kink and favorable
change in growth slope seen in the curves. For some curves the growth slope is zero after an upward change, indicating that 500 g is
the minimal seed weight for plants' survival under such condition
Figure 3 Individual growth of yam for seed wt. 650 gm
Note: In Figure 3 plants with seed weight 650 g are shown. Downward trend is observed from the time of second interim reading,
when yam detachment is made at the time of first interim reading. Less prominent downward trend compared to that for seed weight
500 g is seen; curves have upturn after first intervention. This once again indicates that 500 g is the minimal seed weight for plant
survival under such condition
