YIELD OF INDETERMINATE, SMALL-VINE COWPEA CULTIVARS UNAFFECTED BY UNIFORMITY OF WITHIN-ROW SPACING

Cowpea [Vigna unguiculata (L.) Walp.] planters can produce variable wi thin-row seed spacing. We determined whether precision planting of cow pea would produce a yield advantage over more random planting at the s ame rate. Studies were conducted from May 1992 to Feb. 1993 at three l ocations: Uvalde, Texas; Bixby, Okla.; and FortPierce, Fla. Seeds of t he indeterminate, small-vine cowpea cultivars Mississippi Silver and P inkeye Purplehull BVR were hand-planted at 42 per 3.15 m of row. Seeds within rows were either spaced uniformly at 7.5 cm [control, with SD = 0] or in one of two random sequences (SD = 4.8). At harvest, in Okla homa and Florida, mean within-row spacings were similar, but SD values of random-sequence plots remained greater than those of control plots . Control plots averaged four more plants at harvest than random-seque nce plots in Texas. However, seed yield (seed dry weight per hectare) and harvest index were unaffected by uniformity of within-row spacing at ah three locations. Thus, precision seeding of indeterminate, small -vine cowpea cultivars seems unlikely to produce a yield advantage ove r more random planting at the same rate.