Effects of Soil Fertilizing Management (Organic, Integrated and Chemical) on Forage Yield and Quality Traits of Globe Artichoke (Cynara scolymus)

To study the effect of three soil fertilizing systems (chemical, organic, and integrated) on forage yield and quality of Globe Artichoke (Cynara scolymus) an experiment was conducted using a Randomized Complete Block Design (RCBD) of four replications at the Research Farm of College of Agriculture, University of Tehran, Karaj, Iran in 2006. The treatments included 5 levels of chemical fertilizers (40, 80, 120, 160 & 200 kg/ha of N & of P), (48, 96, 144, 196 & 240 kg/ha of K), 4 levels of manure (10, 20, 30 & 40 ton//h), and 5 levels of mixture of different ratios of fertilizers and manure, as integrated systems along with a control (no fertilizer or manure application). The results showed that soil fertilization treatments significantly affected forage quantity and quality of artichoke. As for chemical fertilizers, total DM yield increased to 4.12 and 3.69 tons/ha through the treatments (in kg/ha) N200/P200/K240 and N160/P160/K192, respectively. For organic systems, the highest yields of 4.12 and 3.7 ton/ha were obtained by treatments of 40 and 30 tons of animal manure/ha, respectively. In the integrated system, the highest DM values of 4.49 and 4.1 tons/ha were obtained for the treatments of N80/P80/K96/manure 20,000 and N120/P120K144/manure10,000, respectively. The effects of three soil fertilization methods on forage quality traits were inconsistent. Chemical and integrated systems increased Crude Protein (CP), total dry matter, Dry Matter Digestibility (DMD) and Water-Soluble Carbohydrates (WSC) compared to the organic system of fertilizing. But organic system increased K and P contents as well as Acid Detergent Fiber (ADF) as compared to integrated and chemical treatment systems. It becomes evident that for chemical systems, moderate and high levels of chemical fertilizer and while for integrated systems, moderate levels of manure and chemical fertilizer exert significant effects on the quality and quantity of Globe Artichoke forage yield but not on DMD, K content, CP% and ADF. DMD and K content (in integrated systems) increased with an increase in manure and a decrease in chemical fertilizer levels. In contrast, CP% and ADF increased with a decrease in manure and an increase in chemical fertilizer levels. It is concluded that artichoke, as a new forage crop, has a suitable quantity and quality potential for livestock feeding when treated with proper of soil fertilization systems. But further and more thorough studies would be needed befor considering Artichoke as a new source of forage feed.