Heatwaves hit menthol crop; oil production drops by almost 40%

Gaura (Barabanki), Uttar Pradesh

Pointing towards the wilted mentha (menthol) crop lying scattered in her field, 55-year-old Maiki Devi said that she had never seen such high crop losses.

"The heat was too much in March which meant that the quantity of water needed to irrigate the fields was much higher. Not being able to irrigate my field during heatwaves led to a stunted growth of the mentha plants because of which almost a quarter of my crop is completely destroyed," Maiki Devi, from Gaura village in Barabanki's Fatehpur block, told Gaon Connection. "The remaining crop is partially dried and the production of oil is almost one third of the usual production," she lamented.

Similar complaints of lower mentha production due to the heatwaves this year are pouring in from a large number of farmers in Barabanki district of Uttar Pradesh. The state contributes to almost 80 per cent of India's total menthol production, which is an important cash crop for hundreds of thousand farmers. The crop is used to make menthol oil which is used in the production of medicinal oils, ointments, flavouring substances, mouth fresheners etc.

Also Read: Rising heat, sinking groundwater and violent conflicts over irrigation in UP. A ground report

This drop in mentha production and menthol oil extraction has been confirmed by the agricultural scientists.

"Uttar Pradesh usually records a mentha crop production of 25,000 MT [metric tonnes] to 30,000 MT every year," Devendra Kumar, a Bareilly-based former program associate at Central Institute of Medicinal and Aromatic Plants (CIMAP), told Gaon Connection. "This year, it is estimated that the heatwaves have seriously hampered the production, which is expected to hover around 18,000 MT to 20,000 MT. The losses could easily be anywhere upto 40 per cent," he added.

According to the state's Department of Horticulture and Food Processing, menthol cultivation is spread across 88,000 hectares and Barabanki district, where Maiki Devi lives, alone contributes about 25 per cent to 33 per cent of the total menthol oil production.

Heatwaves hit several crops

Early onset of the heatwaves has already caused significant damage to the production of crops like wheat, tomatoes, lemons, mangoes and litchi this year and mentha crop is its latest casualty. Rising heat and lack of irrigation facilities is also leading to violent conflicts amongst the farmers in the state, as reported by Gaon Connection last week.

Farmers are staring at heavy losses. Maiki Devi from Gaura village had cultivated mentha on eight bighas (almost two hectares) of land. "Normally, every year, the mentha crop grown on eight bighas produced six tanks of mentha oil. This year, only two such tanks of oil could be produced and the total production is between fifteen to twenty kilos only," she said. One tank holds ten to twelve kilos [kilogrammes] of oil.

Also Read: India among the top 5 countries with highest exposure of vulnerable population to extreme heat : Lancet Report

"I had invested Rs 40,000 on my crop, the oil extracted is not even worth Rs 20,000," the 55-year-old farmer said while roughly calculating her losses.

According to Mahesh Srivastava, District Horticulture Officer in Barabanki, apart from the oppressive heatwaves, the farmers' decision to cultivate crops like watermelons instead of mentha had also resulted in the reduction of the acreage of mentha this year.

"The losses due to early heatwaves has resulted in a decreased production of mentha but many traditional mentha farmers have switched to cultivating watermelons and melons as well. This has reduced the acreage of metha this year," Srivastava told Gaon Connection.

How rising heat affects mentha crop

Saudaan Singh, Senior Scientist at CIMAP explained to Gaon Connection that almost every crop that humans consume has nutrients because the plant's primary metabolites which result in the production of carbohydrates, fats and proteins.

Apart from primary metabolites, the plants also have secondary metabolites. "... And the crops which are not edible but used for their essence or oil (like mentha) produce these oils due to the secondary metabolites, which is technically the plant's defence mechanism against being grazed by an animal," the scientist elaborated.

He went on to explain that under any stress factor like the heatwaves, the plant's metabolism perceives an external threat due to which it intensifies the production of secondary metabolites (which is mentha oil in the present case).

"However, what happens is that when the heatwaves hit, a significant part of the acreage gets completely dried up which results in zero oil content in them. So, the gain in oil content in some of the plants is nullified by the loss overall acreage," said Singh.

According to him, if the heatwave conditions are simulated in lab conditions, the oil content will increase. But out in the open, farmers are at a loss because heatwave conditions cannot be controlled and result in damage to the crops.

"Even if we factor in the gain in oil productivity due to secondary metabolites, the losses would still be around 25 to 30 per cent," the senior scientist said.

"I cultivated mentha on six acres of land and usually I get 20-30 tanks of mentha crop but this year I got only five tanks of the crop. Rest all got damaged or dried off," Rajendra Rajput, a farmer from Jagatpur village in Barabanki's Sooratganj block, told Gaon Connection.

With inputs from Pratyaksh Srivastava in Lucknow.