Integrated nitrogen management in fodder oats (Avena sativa) in hot arid ecosystem of Rajasthan

Abstract

A field experiment was conducted during rabi of 2006-07 and 2007-08 at Bikaner to find out the effect of dif- ferent levels of nitrogen (0, 50, 100 and 150 kglha), biofertilizer (uninoculated and inoculated with Azotobacter) and sheep manure (0 and 10 Vha) on performance of fodder oats (Avena sativa L). Results revealed that 150 kg Nlha significantly increased the growth attributes leading to higher dry matter (11 .I3 Vha) and crude protein yields (988.7 kglha). Seed inoculation with Azotobacter increased the dry matter and crude protein yields by 5.93 and 7.00% over uninoculated control. Sheep manure @ 10 Vha significantly increased the green fodder, dry mat- ter, and crude protein yields to the extent of 21, 22.1 and 26.0% respectively over no sheep manure. Interaction effect of nitrogen and sheep manure was significant and dry matter yields recorded at 100 kg Nlha alongwith 10 t sheep manurelha and 150 kg Nlha alone were at par. Highest values of net returns (Rs 23,285/ha), net B:C ratio (1.00), N, P and K uptake, energy responsiveness (8.32 MJIRe) were recorded at 150 kg Nlha. .However, maxi- mum values of energy ratio (8.26) and energy productivity (458.9 g1MJ) were obtained with 100 kg Nlha, whereas, highest values of agronomic N-use efficiency (43.9 kg dmlkg-N applied) and physiological N-use effi- ciency (68.7 kg dmlkg N uptake) were recorded with 50 kg Nlha. Application of Azotobacter inoculation and sheep manure registered higher values of above traits than their respective control except agronomic and physi- ological N-use efficiencies, where control treatment recorded greater values. The residual soil organic carbon and available N contents were significantly influenced with application of nitrogen and sheep manure. The re- sults show that nitrogen @ 100 kglha alongwith Azotobacter inoculation and sheep manure @ 10 Vha may be applied for higher and quality fodder of oats.