The effect of irrigation frequency on lateral and vertical root growth, and bulb yield of shallots (Allium cepa var. ascalonicum cv. Tropix) was investigated in the field (polytunnel). The experimental treatments were dry (85 l of water; frequency = 12), medium (135 l of water; frequency = 20), and wet (220 l of water; frequency = 36). The wet treatment recorded the highest lateral root growth. Vertical root growth (root depth) was unaffected by irrigation frequency to any significant extent. Number of bulbs per plant was the same in all the three irrigation treatments. The wet- treated shallots had the highest bulb diameter, bulb weight, and bulb yield.


Ghana Jnl.agric. Sci Vol.31(2), 1998: 143-146