Scientific Findings About Organic Agriculture

Effect of Organic, Inorganic Fertilizers on Rice Quality

Background and methodology:

Although nutrient source plays an important role in crop quality, there is little information available on how rice quality is affected by different organic composts. This study was conducted in aromatic rice on two levels of four organic composts made from kudzu vine (Pueraria lobata), nettle (Urtica), Lantana, winter weeds, and two other organic amendments of poultry manure and farmyard manure. The effect of these organic fertilizers on the nutritional and physico-chemical properties and on the cooking quality of the rice was studied, using a fertilized, chemical treatment as positive control.  

Findings:

Results show that grain yield was significantly influenced by the supply of major plant nutrients. The highest rice yield was obtained from the inorganically fertilized plots. The protein content in the grain also was highest in the inorganic treatment and lowest in the control. 

Among organic treatments, farmyard manure contributed the least in terms of protein content. Significantly higher iron content was recorded with organic fertilization compared to inorganic fertilization. However, inorganic fertilization was superior in terms of copper content compared with organic treatments. 

Quality attributes indicated that cooked kernel length was positively correlated with the kernel elongation ratio. Winter weed compost provided comparative benefits for rice yield and quality in terms of protein, iron and head rice recovery compared with other sources of nutrients. The results of this study suggested that organic nutrient sources can perform comparatively well in terms of chemical and physico-chemical properties, and cooking quality of rice.

Reference:

Saha, S., Pandey, A. K., Gopinath, K. A., Bhattacharaya, G. R., Kundu, S., & Gupta, H. S. (2007).Nutritional quality of organic rice grown on organic composts.  Agronomy for Sustainable Development, 27(3), 223-229. Available on-line at:  http://dx.doi.org/10.1051/agro:2007002