Effect of chemical fertilizer and farmyard manure on quantitative and qualitative yield of tobacco (Nicotiana tabacum)

To study the effect of chemical and manure fertilizers on the yield of tobacco, cultivar K326, an experiment was conducted in Taqar Tappeh village (Golestan province) in 2016 in a randomized complete block design with four replications. Treatments including chemical fertilizer (100%), livestock manure (at two levels of 10 and 20 t/ha), the combination of chemical and manure fertilizers (10 t/ha of manure + 50% chemical fertilizer), and no fertilization (control) During the growing period and before harvest, necessary evaluations were performed on leaf length, leaf width, leaf chlorophyll index (spad), leaf fresh weight, leaf dry weight, leaf nicotine percentage, average price and gross income per hectare. The results showed that except for chlorophyll index, mean price and leaf nicotine percentage, other traits such as leaf length and width, fresh and dry leaf weight and gross yield per hectare were statistically significant. Comparison of means also showed that the highest leaf length (63.2 cm), leaf width (32.5 cm), leaf fresh weight (35851 kg/ha.), dry leaf yield (6343 kg/ha.) and gross income (508550072 Rials) was obtained from the combined treatment of 10 t/ha of manure + 50% chemical fertilizer. Therefore, the findings of this study showed that there is a possibility of combined application of chemical and livestock fertilizers without a significant reduction in tobacco leaf yield and no environmental degradation consequential in a sustainable agricultural system.