The persistent fog and biting cold sweeping across Bihar are creating a stark divide in the state's agricultural fortunes. While the chilly conditions are proving beneficial for key rabi crops like wheat and mustard, they pose a severe threat to potato cultivation, potentially slashing yields by half in vulnerable areas.
Potato Crop Under Siege from 'Jhulsa Rog'
Agronomists and farmers have raised an alarm over the impact of prolonged fog, which extends beyond a week, on potato production. The crop, one of the highest-yielding in Bihar, is highly susceptible to late blight, a fungal disease locally known as "Jhulsa Rog." This threat is most acute in northern Bihar, where temperatures have dropped rapidly.
Dinesh Rai, an associate professor of pathology at Dr Rajendra Prasad Central Agricultural University (RPCAU) in Pusa, explained the cause. "The high moisture and humidity during dense fog trigger Jhulsa Rog," he said. While harmful, the disease can be managed through regular light irrigation and timely application of fungicides.
High Economic Stakes and Expert Warnings
The economic implications are significant, especially in major potato-growing districts such as Katihar and Purnia. R K Sohane, a senior professor at Bihar Agricultural University (BAU) in Sabour, warned of substantial losses. "Late blight can cause potato yield loss of up to 50% in these two districts and other parts of the state," he stated. However, he confirmed that no cases have been reported hindering yields in the current season so far.
Detailing the financial volatility, R K Tiwari, a senior scientist at Krishi Vigyan Kendra in Birauli, Samastipur, provided a breakdown. "One hectare can yield 25 tonnes of potatoes in a good season. But if blight strikes, yields can plummet by up to 80%, and earnings may drop by 60%," he said.
Silver Lining for Wheat and Mustard
On the brighter side, the cold wave is a boon for other winter crops. Professor Sohane highlighted the benefits for wheat, noting that the chill improves the protein content and processing quality of wheat. Furthermore, the biting cold helps reduce the survival of insects and pathogens, which lowers pest pressure for the upcoming growing season.
Elaborating on wheat's prospects, R K Tiwari said, "A good season can produce 50 quintals of wheat per hectare. With a minimum support price of Rs 2,200 per quintal and cultivation costs around Rs 40,000 to 45,000, a farmer can net up to Rs 60,000 per hectare."
However, the news is not good for all produce. Sohane added that low temperatures significantly hinder the growth of tomatoes and other vegetables by reducing photosynthesis and delaying flowering, leading to poor quality and reduced yields.
Managing the Risks and Future Outlook
To combat the threat to potatoes, experts recommend a multi-pronged approach: using disease-free seeds, burning infected plant debris, and applying fungicides like Mancozeb.
Mukesh Kumar, a professor of agronomy at RPCAU, offered a nuanced view on the fog's duration. "In general, fog is helpful for agriculture for up to one week; anything beyond that hampers growth and yield," he observed. He added that if the current low temperatures continue without the accompanying fog, it would be highly beneficial for crops, especially since winter arrived early this year.
The contrasting impact of Bihar's weather underscores the delicate balance farmers must maintain, where the same climatic condition can be a friend to some crops and a formidable foe to others.
