Striga asiatica growth and seed production in response to organic and inorganic P - fertilizers

Abstract

The measures for Striga management are hindered by a unique survival strategy of the weed, whereby it produces large amount of seeds. Therefore, prevention of further build up of the Striga seed bank through control measures remains an essential component in Striga control. The influence of fertilizers on Striga seed production was studied for two consecutive years (2009/2010 and 2010/2011) at Hombolo Research Station-Dodoma, Tanzania. Farmyard manure (5.9 tons/ha equivalent to 50 kg N/ha), chicken manure (2.5 tons/ha equivalent to 50 kg N/ha), urea (50 kg N/ha) and triple superphosphate (TSP) (40 kg P/ha) were tested on sorghum variety Macia in a randomized complete block design replicated four times. Striga plants supplied with chicken manure, urea and TSP had significantly fewer Striga capsules per plant than farmyard manure treated and control (without fertilizer application) plants. However, the mechanism by which phosphorus application reduced Striga reproduction in the current study is yet unclear. Based on this study, fertilizers have the potential to reduce Striga reproduction. Even though fertilizers play a significant role in Striga reproduction, calculations of the seed production per Striga plant indicated that considerable amounts of seeds were still added to the soil.