Onion yields under three water regimes and five spacings

Abstract

The objective of this study was to evaluate the effect of three irrigation regimes and five crop spacings on onion crop yield. The experiment was carried out under a randomized block design, in a split-plot scheme with three replications. The irrigation regimes consisted of the maintenance of the matric potential in the root zone with the following bands: regime 1, between -6.0 and -8.5 kPa; regime 2, between -7.0 and -10.0 kPa; regime 3, between -10.0 and -28.0 kPa. The crop spacings which constituted the sub-plots were: 0.30 x 0.08 m; 0.20 x 0.08 m; 0.10 x 0.08 m; 0.15 x 0.10 m; and, 0.10 x 0.10 m. The largest marketable productivity of large and medium-sized bulbs and the largest bulb mean weight ocurred under regime 1. Spacing 0.20 x 0.08 m resulted in the highest productivity of commercial bulbs. Spacings of 0.20 x 0.08 and 0.30 x 0.08 m resulted in large and medium-bulbs and in largest average bulb weight.