Fallow rotation with three weed species for <i>Striga hermonthica</i> control and maize productivity at Minna, Nigeria

Abstract

The potential benefits of planted fallow rotation with weed species: Hyptis suaveolens (L.) Poit. (Bush tea), Desmodium intortum (Mill.) Urb. (Greenleaf Desmodium) and Senna obtusifolia (L.) Irwin & Barneby (Sicklepod) were investigated on-farm for Striga control, growth and yield of maize. The treatments were one and two - years H. suaveolens, D. intortum and S. obtusifolia fallows, natural fallows and no fallow cropping plot arranged in a randomized complete block design with three replications. Results show that planted H. suaveolens fallow added more organic carbon after one or two years and more available phosphorus after two years. Planted S. obtusifolia added more total nitrogen compared to other fallows and no fallow after two years. Delay in Striga shoot emergence and reduction in Striga shoots density were lowest in H. suaveolens D. intortum and S. obtusifolia planted fallows after two years. Taller maize plants, bigger and longer cobs, and more grains per cob were significantly (p<0.05) associated with D. intortum and S. obtusifolia planted fallows. Maize grain yield was highest in S. obtusifolia planted fallow compared to that in the natural fallow plot after one and two years. Grain yield from S. obtusifolia one and two years fallows were 36.8 % and 34.9 % greater than that of natural fallow, respectively. These results suggest that S. hermonthica sick land can be fallowed for a minimum of two years with any of the three weed species for increased maize growth and grain yield as part of an integrated management strategy.