تغییرات عملکرد ذرت و برخی ویژگی‌های خاک تحت تاثیر برهمکنش مقادیر بقایا و فواصل آبیاری در سامانه حفاظتی

The current study was conducted in order to examine the effect of different wheat residues on yield, yield components and soil properties as affected by three irrigation intervals in a no-tillage system as a 2-yrs field experiment at College of Agriculture, Shiraz University. Wheat resides were in four levels: no residues (as control), 25, 50 and 75% of ground cover and irrigation intervals were at three levels: 12, 16 and 20 days. The results showed that in control conditions, residues caused reduction in maize growth and yield. Although drought stress, due to increase in irrigation interval, decreased thousand grain weight, grain yield, biological yield and harvest index, as well as, organic matter in all residues rates; however, the highest reductions were observed in no-residues treatment. With residues application organic matter and carbon to nitrogen ratio were increased. The highest maize growth was obtained from no residues at normal irrigation and from 25% residues at drought stress conditions; which showed role of low residue in maintain of soil moisture. Overall, maize grown in 25% residues in region with limited water source same is recommendable.
Key words: Conservation tillage, Drought stress, Harvest index.