Effect of chemical fertilizers, compost and irrigation regimes management on yield and agronomic propertiesof rice, cultivar Hashemi

The use of compost with chemical fertilizers is recognized as necessity for sustainable agriculture.To evaluate the effect of compost and chemical fertilizers under different irrigation regimes on rice morphological characteristics, a split plot experiment in a randomized complete block design with three replications was conducted at Rice Research Institute of Iran, Rasht, Iran, during 2013 and 2014. Irrigation regimes were 1.3 (control), 1 and 0.7 fold evaporation from the evaporation pan (Ep) as the main plot and six different fertilizers as the sub plots,C1=control, C2=N60- P30- K60 kg.ha-1, C3= C2 compost (5 ton/ha), C4= N60 kg.ha-1 compost (5 ton/ha), C5= P30- K60 kg.ha-1 compost (5 ton/ha), and C6= compost(5 ton/ha). The results of the first year showed that the interaction of irrigation levels and fertilizers was significant at 1% probability level on all measured traits except for 1000 grain weight. In the second year,this interaction was also significant on the number of tiller, plant height, biologicyield, straw yield and grain yield at 1% probability level and on panicle lengthat 5% probability level, but had not significant effect on the other traits.The most appropriate management of irrigation was one-fold evaporation from the evaporation pan with the use of recommended amount of nitrogen fertilizer and compost (5 ton/ha), which in addition to reducingthe environmentalproblems caused by uncontrolled use of chemical fertilizers, especially phosphorus and potassium fertilizers, about 21.18 percent of the water consumption was consumed.