Three treatments were used to evaluate the effects of missing plants on sweetpotato yield: a single plant missing, two adjacent plants missing and two plants missing separated by a single plant. Individual plant yields of the four plants in the same row in each direction from the missing hill were taken. Yields were also taken from corresponding plants in the rows on each side of the row with the missing plant. A plot therefore consisted of three rows with the center row containing eight or nine plants and one or two missing hills and the other two rows containing nine to 12 plants. A single missing plant tended to increase yield of all grades of the plant in the same row next to the missing hill, but differences were nonsignificant. Two missing plants did not result in individual plant differences, but did increase overall plot yield of jumbo and cull grades. The single plant between two missing hills produced a greater number of small-sized No. 1 roots. No. 1 yield of plants in adjacent rows across from the single plant produced lower No. 1 yields.
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