برهمکنش تنش خشکی انتهای فصل و مصرف کودهای آلی بر عملکرد گندم نان (Triticum aestivum)

The effects of drought stress at different growth stages and nutrition systems were studied on yield and yield components of wheat (Chamran cv.). This experiment was carried out as split plot based on completely randomized blocks design with three replications at Research Farm of Ramin University of Agriculture and Natural Resources, Khuzestan province, Iran, during 2009-2010. Irrigation at three levels of I1 (irrigation cut-back from spike formation stage to harvesting, 55 zadox), I2 (irrigation cut-back in anthesis stage to harvesting, 65 zadox) and I3 (full irrigation, control) were in main plots, and fertilizer systems including chemical fertilizer (NPK), manure (M), biological fertilizer (B) and manure + biological fertilizer (MB) were in sub-plots. Results showed that drought stress and nutrition systems had significant effect on grain yield and biological yield (P<0.01) and fertilizer system affected harvest index (P<0.05). Maximum grain yield (5304 kg/ha) was obtained in I3 treatment and minimum grain yield (3413 kg/ha) was in I1 treatment. In fertilizer treatments, maximum grain yield (5081 kg/ha) belonged to MB and minimum grain yield (3142 kg/ha) to B treatments. According to the results, application of manure plus biological fertilizer improves grain yield of wheat, even under drought stress.