Response of Sesame (Sesamum indicum L.) to Inorganic Nitrogen Application Rates and Organic Fertilizers on Grey Soil in Hochiminh City, Vietnam
Nguyen Thanh Binh *
Graduate School of Environmental and Life Science, Okayama University, Japan and Faculty of Agronomy, Nong Lam University, Ho Chi Minh City, Vietnam
Nguyen Thi Thuy Lieu
Faculty of Agronomy, Nong Lam University, Ho Chi Minh City, Vietnam
*Author to whom correspondence should be addressed.
Abstract
The organic/inorganic fertilizers can contribute substantial N for sesame, but it is not clear that such nitrogen forms are available for plant uptake. A field experiment at agricultural farm of Nong Lam University in HCMc was conducted to study the effect of four inorganic nitrogen application rates (0, 30, 60 and 90 kg N/ha) in combination with two tons of either cow manure or commercial bio-organic fertilizer (BOF) on growth and yield of sesame. The experiment comprised of 2×4×3 factorial in a Split-plot design with three replications. The results show that two organic fertilizers with low nitrogen contents (5–10 g N/kg) and high C/N ratios (28–30) by themselves are not capable of supplying enough nitrogen for sesame requirement. The additional application of inorganic nitrogen at rate of 30 kg N/ha resulted in maximum plant height (106.4 cm), number of capsules/plant (60.13), weight of capsule (1.01 g), number of seeds/capsule (71.0), weight of 1000 seeds (2.63 g), and highest actual yield (0.85 ton/ha). The combination of organic with inorganic N fertilizer, therefore, needs to consider the effective use of nitrogen from each source to maintaining sesame yield, while avoiding undesirable environmental impacts.
Keywords: Bio-organic fertilizer, cow manure, inorganic nitrogen, sesame, seed yield