Effects of rotation of trap crop varieties on the reaction of some cereal host crops to Striga hermonthica biotypes

摘要

Trials were conducted in the screen house of Niger State College of Agriculture, Mokwa (09° 181N; 05° 041E) in 2005 and 2006 to evaluate the influence of rotation of non-host trap crops on the different reaction of host crop genotypes to the parasitism of?Striga hermonthica?biotypes. A split-split arrangement in a complete randomized design with three replications was adopted.? The three varieties each of the host crops, maize (Acr.97 TZL Comp.1-W, 9022-13 and 8338-1), rice (FARO 40, WAB 56-50 and FARO 45) and sorghum (SAMSORG 3, ICSV111 and SAMSORG 14) with and without?Striga?infection constituted the main-plot treatments. The sub-plot treatments were the three trap crop varieties each of groundnut (SAMNUT 10, SAMNUT 11 and SAMNUT 18), cowpea (SAMPEA 6, SAMPEA 7 and L25), soybean (TGx 1448-2E, TGx 1485-1D and SAMSOY 2) and cotton (SAMCOT 8, SAMCOT 9 and SAMCOT 10) while the sub-sub plot treatments consisted of crop sources (millet, maize and sorghum) of?Striga?collected in the two years.? The result obtained indicated that the genotypes of maize (9022-13 and Acr.97 TZL Comp.1-W), rice (FARO 40 and WAB 56-50) and sorghum (SAMSORG 3) exhibited various levels of resistance to?Striga?parasitism by supporting lower infestation, exhibition of lower reaction syndrome and higher crop growth vigour as well as production of higher shoot dry matter than the respective susceptible varieties.? The host crops exhibited differential reactions to different?Striga?biotypes following the order sorghum > millet > maize. Host crops preceded by rotation of groundnut var. SAMNUT 11, soybean var. TGx 1448-2E, cowpea var. SAMPEA 7 and cotton var. SAMCOT 10 consistently had greater reduction of?Striga?parasitism and increased growth vigour and productivity.