Are your staple rice and wheat losing their nutrients?

Context:

Today’s rice does not have the same density of essential nutrients as those cultivated 50 years ago, notes a new study.

Relevance:

GS-III: Agriculture

Dimensions of the Article:

1. Loss of nutrients in rice and wheat
2. Way forwards suggested
3. Understanding Biofortification

Loss of nutrients in rice and wheat

• Zinc and iron concentrations in grains of rice cultivars released in the 1960s were over 25mg/kg and almost 60mg/kg respectively and this depleted to just over 20mg/kg and less than 45mg/kg respectively in the 2000s.
• In wheat, the concentrations of zinc and iron was over 30mg/kg and over 55 mg/kg respectively in 1960s and this dropped to just over 20mg/kg and 45mg/kg respectively in 2010s.
• Zinc and iron deficiency affects billions of people globally and the countries with this deficiency have diets composed mainly of rice, wheat, corn, and barley.
• Though the Indian government has taken initiatives such as providing supplementation pills to school children, it is not enough. We need to concentrate on other options like biofortification, where we breed food crops that are rich in micronutrients.

Reason for the decline in nutrients

• There could be several possible reasons for such depletion: one is a ‘dilution effect’ that is caused by decreased nutrient concentration in response to higher grain yield.
• This means the rate of yield increase is not compensated by the rate of nutrient take-up by the plants. Also, the soils supporting plants could be low in plant-available nutrients.

Way forwards suggested

• Growing newer-released (1990s and later) cultivars of rice and wheat cannot be a sustainable option to alleviate zinc and iron malnutrition in Indian population.
• The negative effects need to be circumvented by improving the grain ionome (that is, nutritional make-up) while releasing cultivars in future breeding programmes.
• There is a need to concentrate on other options like biofortification, where we breed food crops that are rich in micronutrients.

Understanding Biofortification

• Biofortification is the idea of breeding crops to increase their nutritional value. This can be done either through conventional selective breeding, or through genetic engineering.
• This is an important improvement on ordinary fortification when it comes to providing nutrients for the rural poor, who rarely have access to commercially fortified foods.
• As such, biofortification is seen as an upcoming strategy for dealing with deficiencies of micronutrients in low and middle-income countries.

Biofortification Initiatives Taken by India

• Recently, 17 biofortified varieties of 8 crops was dedicated to the nation such as Rice- CR DHAN 315 has excess zinc, Wheat- HI 1633 rich in protein, iron and zinc, Maize- Hybrid varieties 1, 2 and 3 are enriched with lysine and tryptophan, etc.
• Madhuban Gajar, a biofortified carrot variety, is benefitting more than 150 local farmers in Junagadh, Gujarat. It has higher β-carotene and iron content.
• ICAR has started Nutri-Sensitive Agricultural Resources and Innovations (NARI) programme for promoting family farming linking agriculture to nutrition, nutri-smart villages for enhancing nutritional security and location specific nutrition garden models are being developed to ensure access to locally available, healthy and diversified diet with adequate macro and micronutrients.
• The production of bio-fortified crop varieties will be upscaled and linked with government programmes of mid-day meal, Anganwadi etc. to reduce malnutrition.

-Source: The Hindu