بررسي اثرات زيرشكن و دور آبياري به ازاي مقدار معيني از نياز آبي گياه بر ميزان محصول پنبه در داراب

The Effects of Subsoiling and Irrigation Frequency With Constant Crop Water Requirements on Cotton Yield in Darab

Subsoiling is used to loosen hardpan and increase rooting depth and water availibility. This study evaluated cotton response to loosen hardpan and different irrigation frequency with canstant crop water requirements. The irrigation frequency as mainplots at three levels: W.R1:35 and W.Rz:50 and W.R3:65 milimeter water requirements and tillage systems as subplots at two levels as follows:(1): moldboard plowing plus disc harrow (MB.P) and (2):subsoiling to a depth of 45-50 cm plus moldboard plowing and disc harrow (SS+MB.P) were used with five replication. Yield and yield components, cone index and hulk density were measured for all treatments. The results showed that different tillage methods had no significant effect on crop yield. Maximum yield was obtained in (SS+MB.P) method and there was also no significant difference in yield between use of(SS+MB.P) and ( MB.P) methods. Maximum and minimum amount of yield was occurred when irrigation frequency was done at 50 and 35 mm crop water requirements, respectively.