Nutrient variability of rice landraces (Oryza sativa L.) from Manipur, Northeast India and its nutrients supply potential in rice-based diets

Abstract

PurposeRice landraces are essential for supplying beneficial traits for developing improved rice varieties with better nutritional quality. Nevertheless, in a yield-driven environment, grain nutritional quality has been ignored especially that of rice landraces. Given this, the purpose of this study is to evaluate the content and nutritional variability of rice landraces from Manipur.Design/methodology/approachThirty-three most popular rice landraces were collected as dry paddy samples from Manipur and transported to the National Institute of Nutrition, Hyderabad, by air. All the paddy samples were processed and analyzed for 35 nutrient parameters using standard methodologies.FindingsThe mean nutrient content of Nagaland brown rice was: protein 7.5 ± 0.8, fat 3.0 ± 0.3, TDF 5.5 ± 0.4 and ash 1.2 ± 0.2 g/100g. The range of water soluble-vitamin content in mg/100g, was 0.1–0.43 for Thiamine and for Niacin 2.1–3.5, while the content in µg/100g was 40–64 for Riboflavin, 0.5–3.9 for Pantothenic acid and 20–118 for Pyridoxine. A relatively large coefficient of variation was observed for iron (25%), manganese (28%), copper (32%), calcium (13%) and phosphorus (11%). Manipur rice landraces have significantly higher total dietary fiber and lower phytate contents than modern varieties. Milling led to steep losses of nutrients, and limiting to 5% milling substantially improves nutrient retention in milled rice.Research limitations/implicationsFuture nutrition interventions should use rice with superior nutrient quality to improve nutrient intakes. Manipur rice landraces conserved over generations can broaden the genetic base of breeding stocks especially in the face of climate change.Originality/valueThe paper presents comprehensive nutritional data of 33 rice landraces from the state of Manipur, India. The results indicate large nutrient variability even within these 33 rice landraces with important traits such as high total dietary fiber and low phytate contents. The study highlights the importance of conserving the existing rich genetic material of Manipur rice landraces to develop varieties that combine higher yields with stress tolerance and superior grain nutritional value to improve the food and nutrient security.