EFFECT OF MULCHING ON ROOT ZONE MOISTURE CONTENT AND YIELD OF DIFFERENT SUNFLOWER VARIETIES UNDER RAINFED CONDITIONS

The research study was conducted at Barani Agricultural Research Station, Kohat , NWFP during spring season , 1999 . The main objective of the study was to investigate the effect of mulching on root zone moisture content and yield of different sunflower varieties under rain fed conditions . The experiment was conducted with five varieties of sunflower and two types of mulches with two different rates , i.e. 4 & 5 t/ ha using randomised Complete Block Design with split plot arrangement . Five treatments were assigned . Control ( T1 ) , wheat straw at the rate of 4 ton /ha  ( T2 ) , wheat straw at the rate of 5 ton /ha ( T3)  , grass hay straw at the rate of 4 ton/ ha ( T4)  , and grass hay straw at the rate of 5 ton/ ha ( T5 ) . The plot size was 6 m \ Soil physical and chemical properties were determined in laboratory.  Eta was determined by depletion method . The consumptive use ( Eta)  of sunflower during mulching period was  248.3mm ( T5) . Results on yield and its components indicated that mulching had significant effect on all yield components . The maximum yield of 524.9 kg/ha was obtained in the plot covered by wheat straw at the rate of 5 - ton/ha  ( T3) . Based on this study , it can be concluded that wheat straw and massive hay straw should be applied at 5 ton /ha for having maximum yield with light irrigation in flowering and grain formation stages .