تاثير عمليات پيش كاشت بر عملكرد گندم در شرايط آب و هوايي اهواز

The Effect of Various Preplanting Treatments on Wheat Yield in Ahvaz Climatic Condition

The effect of different preplanting treatments on yield of wheat (cultivar: Chamran) was compared with burning the harvest residuals as traditional farming system (a6), and with no residuals left from previous crop (a8). Preplanting treatments included: mixing the total wheat straw produced by previous crop with soil (a3), mixing wheat crop residue after taking out straws from the field (a4), planting a crop (as green manure) with total wheat straw (al,a5), and planting a crop (as green manure) with previous crop residue after removing a part of straws from the field (a2,a7). These preplantings were combined with three levels of fertilizers; i.e. b1 for high yielding potential (to produce 7 tons/ha grain yield), b2 for medium yielding potential (to produce S tons/ha grain yield), and b3 for ordinary yielding potential (to produce 3 tons/ha grain yields). The experiment was conducted at the experimental farm, College of Agriculture, Chamran University, Ahvaz during 1999-2000 planting season. The preplanting treatment were applied in early fall season and main crop was planted in December. The results showed that mixing the whole straw with soil increased grain yield of wheat probably because of enough soil moisture for relative straw decomposition (52.2 mm rainfal in fall 1999 before sowing). No nitrogen uptake retardation has been observed.. The same situation was observed for medium level of fertilizer consumption. Mixing the total straw with soil, despite common ideas, caused an increase in wheat grain yield.