Biofertilizers and Drought Stress Effects on Yield and Yield Components of Fennel (Foeniculum vulgare Mill.)

Effects of biofertilizers and stacosorb polymer* on yield and yield components of fennel (Foeniculum vulgare Mill.) under drought stress were evaluated using a split-factorial experiment based on a randomized complete block design (RCBD) with three replications at the agricultural research farm of Lorestan University, Khorramabad, Iran in 2013. The factors included drought condition (stressed and non-stressed) in the main plots, biofertilizer (nitroxin and barvar-2 phosphate) and stacosorb polymer [control and non-control] in the sub-plots.  Results showed use of the biofertilizers had positive effects on the umbel number per plant, seed number per umbel, seed number per plant, harvest index, total dry matter, seed yield, plant height, and essential oil yield and percentage. The use of stacosorb had a significant positive effect on the plant height and seed number per plant under drought condition. The highest 1000-seed weight (4.82 g) was recorded in treatment with no fertilizer in the non-stressed plots. The highest total dry matter (192.7 g/m2) and seed yield (56.57 g/m2) were obtained from treatment with nitroxin in the non-stressed plots. The highest harvest index (45.24%) was recorded in treatment with the barvar-2 phosphate biofertilizer in the non-stressed plots. In conclusion, the biofertilizers affected significantly on some important traits of fennel. Also stacosorb polymer could counteract the unfavorable consequences of drought stress.