Experiments were conducted to study the effect of inorganic, organic and combined inorganic + organic fertilizer and natural shade under Gliricidia on the growth and dry matter (DM) yield of the medicinal plant Solanum virginianum Schrad. The yield of total dry matter and of different plant parts were also studied in plants harvested at 70, 90 and 110 days after establishment. Application of co...

Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertil...

Soil physicochemical properties, soil microbial biomass and bacterial community structures in a rice-wheat cropping system subjected to different fertilizer regimes were investigated in two seasons (June and October). All fertilizer regimes increased the soil microbial biomass carbon and nitrogen. Both fertilizer regime and time had a significant effect on soil physicochemical properties and ba...

This paper summarizes a series of field experiments that investigated the effects of organic and inorganic nutrients on sweet potato tuber yield in the humid lowlands of Papua New Guinea. In the first experiment, plots were planted with Piper aduncum, Gliricidia sepium and Imperata cylindrica, which were slashed after one year, whereafter sweet potato was planted. Sweet potato yield was lowest ...

To prevent nutrient limitations to crop growth, nitrogen is often applied in agricultural systems in the form of organic inputs (e.g., crop residues, manure, compost, etc.) or inorganic fertilizer. Inorganic nitrogen fertilizer has large environmental and economic costs, particularly for low-input smallholder farming systems. The concept of combining organic, inorganic, and biological nutrient ...

Measurements of methane (CH(4)) and nitrous oxide (N(2)O) fluxes have been extensively taken following rice seedlings transplanted into paddy fields, while little is known about CH(4) and N(2)O fluxes from rice seedling nurseries. Fluxes of CH(4) and N(2)O were simultaneously measured in rice seedling nurseries under the water regimes of continuous flooding and moist irrigation without waterlog...

Nitrogen is an essential element for plant growth and development; however, due to environmental pollution, high nitrate concentrations accumulate in the edible parts of these leafy vegetables, particularly if excessive nitrogen fertilizer has been applied. Consuming these crops can harm human health; thus, developing a suitable strategy for the agricultural application of nitrogen fertilizer i...

Recent research on seeds of bio-diesel plants like Jatropha curcas, constituting 40-50% bio-crude oil indicates its potential as one of the most promising alternatives to conventional sources of energy. Also, limited studies on utilization of de-oiled cake have revealed that Jatropha bio-waste has good potential to be used as organic fertilizers produced via aerobic and anaerobic treatment. How...