Effect of Biological Fertilizer and Fertilization Management on Some Growth Indices of Two Maize Varieties

To study the effects of different fertilization systems on some growth indices of two maize (Zea mays) varieties، a factorial experiment was conducted based on randomized complete block design with three replications at Agricultural Research Station of University of Kurdistan in 2012. Factors were: different fertilizer levels including (T1) chemical fertilizers (nitrogen and phosphorus as much as 300 and 150 kg. ha-1)، (T2) biological fertilizers (Barvar-2 phosphate biofertilizer (100 g. ha-1) and Nitroxin bio-fertilizer (1 L. ha-1)، (T3) chicken manure (15 ton. ha-1)، (T4) 50% chicken manure + bio-fertilizers، (T5) 50% chemical fertilizer + bio-fertilizers + 50% chicken manure، (T6) control (without fertilizer) and maize varieties including (A1) SC704 cultivar and (A2) DC370 cultivar. Results showed that T5 significantly had the highest total dry weight، leaf area index (LAI)، crop growth rate (CGR) and net assimilation rate (NAR) in SC704. In DC370 the highest total dry weight، LAI، CGR، and NAR obtained from T1. In both cultivars the highest RGR belonged to T5، 21 days after sowing. In different fertilize levels، late maturing SC704 cultivar had more yield than that of DC370. Integrated use of organic، biological and chemical fertilizers caused to produce highest yield compared with application of fertilizers alone.