Effect of Different Amounts of Compost on Canola Yield and Water and Nitrogen Use Efficiency

Conversion of organic matter of municipal waste into compost and its use in agriculture, in addition to reducing pollution and improving the quality of the environment can be effective in improving soil fertility. In this study, the effect of different amounts of this type of compost on yield components, grain yield, oil percentage, nitrogen use efficiency and green water use efficiency of winter canola was investigated under a randomized complete block design with 6 treatments and 3 replications. The required experiments were conductrd during a canola growing season in a research farm in Sari city in Mazandaran province. Experimental treatments were compost application at the rate of 10 and 25 tons per hectare (C10 and C25), chemical fertilizer consumption at the rate of 500 kg per hectare (F500), two combined treatments at 0.5 tons of compost per hectare with 400 kg of chemical fertilizer per hectare (C0 .5F400) and 0.2 tons of compost per hectare with 400 kg of chemical fertilizer per hectare (C0.2F400) and control treatment (Control). At the end of the growing season, number of plants per square meter, number of pods per plant, number of seeds per pod, 1000-seed weight, grain yield, nitrogen uptake by the plant and canola oil content were measured and analyzed by SAS software. Also, the green water use efficiency and nitrogen use efficiency were calculated. Based on the results of analysis of variance, the treatments significantly affected on the number of lateral branches, number of pods, number of plants and grain yield was significant. The highest number of lateral branches per plant and the highest number of plants were obtained in F500 and C25 treatments, respectively. The number of pods and grain yield in F500 treatment were significantly different from its value in control and C10 treatments. The highest amount of seed oil was related to F500 treatment, which was significantly different from the control treatment. The highest green water use efficiency was related to F500 treatment followed by and C25. The use of 25 tons of compost per hectare increased the water use efficiency by 0.49 kg/m3 compared to the control treatment. Based on the results, municipal waste compost can be a good alternative to chemical fertilizers for winter canola cultivation in paddy lands.