Orobanche Threat to Mustard Latest News
- Mustard is India’s largest indigenous source of edible oil, cultivated across nearly nine million hectares, mainly in Rajasthan, Uttar Pradesh, Madhya Pradesh, Haryana and West Bengal.
- However, the crop is increasingly threatened by Orobanche aegyptiaca, a parasitic weed that attaches to mustard roots and siphons off water and nutrients, leading to poor plant growth and reduced seed yields.
How Orobanche Damages the Crop
- Orobanche attaches itself to mustard roots underground and siphons off water, nutrients and carbon.
- This leads to wilting, yellowing, stunted plant growth and ultimately sharp declines in seed yields.
- Because the parasite remains hidden below the soil initially, damage is already extensive by the time it becomes visible.
Farmers See Sharp Yield Losses
- Farmers report steep yield declines despite following recommended control measures.
- In Haryana’s Sirsa district, yields have fallen from 9–12 quintals per acre earlier to nearly 6 quintals per acre in recent seasons.
- Even herbicide sprays have shown little effect, pushing farmers to reduce mustard acreage in favour of wheat, chickpea and barley.
Why Infestation Is Spreading Fast
- Each Orobanche plant produces thousands of tiny seeds that can remain viable in soil for up to 20 years and spread through wind and water.
- Fields repeatedly planted with mustard are especially vulnerable, as irrigation creates ideal conditions for seed germination and rapid underground attachment to crop roots.
- The rising infestation has shaken farmer confidence in mustard, traditionally valued for its low irrigation needs.
- As Orobanche spreads, many farmers are cutting back on mustard cultivation, raising concerns over future domestic edible oil production.
Why Mustard Matters for India
- Mustard is India’s most important edible oilseed crop, contributing over 4 million tonnes out of the country’s 10.5–10.6 million tonnes of annual indigenous edible oil production.
- It is central to efforts to cut India’s heavy dependence on edible oil imports.
- Reducing Import Dependence - India imports nearly 16 million tonnes of edible oils every year — mainly palm, soybean and sunflower oil — costing $15.9 billion in 2023–24 and $18.3 billion in 2024–25.
- Improving mustard yields is therefore a key national priority to reduce this import bill.
- Rising Disease and Pest Pressure - Mustard’s increasing vulnerability to Orobanche (margoja), along with pests like aphids and fungal diseases such as white rust, leaf blight, stem rot and powdery mildew, has emerged as a serious concern for productivity and farmer confidence.
Farmers Flag Changing Threat Patterns
- Farmers report that Orobanche infestation is now appearing earlier in the crop cycle and in fertile soils, unlike earlier when it emerged later and mostly in sandy fields.
- This shift signals a growing and more aggressive threat.
- The buildup of long-lasting Orobanche seed banks in soil has increased the weed’s damage potential, enabling early emergence and greater yield losses.
- This has left farmers increasingly uncertain, sowing mustard largely on hope rather than confidence.
Herbicides as a Possible Control Tool
- Chemical control using herbicides such as glyphosate is one possible way to tackle Orobanche.
- However, this approach has major limitations with conventional mustard varieties.
Why Conventional Herbicides Don’t Work
- Glyphosate and similar broad-spectrum, non-selective herbicides kill all plants by blocking the EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) enzyme essential for protein formation.
- Applied to normal mustard, they destroy the crop along with the weed.
- At currently recommended low doses, they are also ineffective against Orobanche.
Role of Herbicide-Resistant Mustard
- A new approach lies in breeding mustard varieties that can tolerate specific herbicides.
- Farmers are testing a hybrid mustard that is resistant to imidazolinone herbicides, allowing selective control of Orobanche without harming the crop.
- The hybrid ‘Pioneer-45S42CL’ can tolerate imazapyr and imazapic herbicides.
- Sold with a compatible herbicide formulation, it requires a single spray after 25 days of sowing and has shown encouraging early results in farmers’ fields.
GM Mustard as a Future Option
- Researchers have also developed GM mustard lines resistant to glyphosate and other herbicides, offering multiple chemical options and reducing the risk of resistance buildup.
- Given mustard’s strategic importance and the rising weed threat, policymakers face a critical decision on permitting GM crops.
- Any decision, experts argue, should be guided by science and farm economics rather than ideology.
Source: IE
Orobanche Threat to Mustard FAQs
Q1: What is the Orobanche threat to mustard crops?
Ans: The Orobanche threat to mustard comes from a parasitic weed that attaches to roots, stealing water and nutrients, causing stunted growth and heavy yield losses.
Q2: Why is the Orobanche threat to mustard hard to detect early?
Ans: The Orobanche threat to mustard remains underground initially, and by the time shoots appear above soil, irreversible crop damage has already occurred.
Q3: Why is the Orobanche threat to mustard spreading rapidly?
Ans: The Orobanche threat to mustard spreads due to long-lived soil seed banks, repeated mustard cultivation, irrigation-triggered germination, and wind- and water-based seed dispersal.
Q4: Why does the Orobanche threat to mustard matter for India’s economy?
Ans: The Orobanche threat to mustard endangers India’s biggest edible oil crop, risking higher import dependence and undermining efforts to reduce the edible oil import bill.
Q5: How are farmers tackling the Orobanche threat to mustard?
Ans: Farmers are testing herbicide-resistant mustard hybrids and selective herbicides, while scientists explore GM mustard lines to manage the Orobanche threat to mustard sustainably.
