"A perception is gaining ground that the government is slow in responding to the crisis in the countryside," said D.H. Pai Panandiker, president of the RPG Foundation think-tank in New Delhi. "Any inept handling of the situation will only invite trouble and impair the plans for economic reforms."
Farming accounts for only 15 percent of India's $2 trillion economy but provides a livelihood to 60 percent of its 1.25 billion people. A crisis in the countryside would have severe political impact.
The opposition Congress party, crushed by Modi a year ago, is latching on to rising discontent in the countryside.
Party leader Rahul Gandhi has been touring the affected farming regions and the heir apparent to the Nehru-Gandhi political dynasty is getting a good response.
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"While Modi has failed to help us, Rahul Gandhi was here to assuage our pain," said Paramdeep Singh, a wheat farmer at Khanna wholesale market in the northern Indian state of Punjab.
"His visit has forced the government to at least acknowledge the fact that we've suffered huge losses."
The fightback by the opposition has slowed Modi's reform agenda in parliament. This week, Congress delayed bills that would make it easier for corporations to buy land - changes it says are "anti-farmer" - and harmonize national and state taxes.
Draw the sting
Finance Minister Arun Jaitley said last week agriculture was the biggest challenge for India's economy and would need major investments.
Meanwhile, Modi's government has asked state governments to tap into more than $1 billion from the State Disaster Response Fund and raised compensation by 50 percent for farmers suffering crop losses.
In an attempt to draw the sting of falling exports and prices, the government has also eased quality requirements for wheat purchases by state agencies, raised import taxes on rubber and sugar, and given an incentive for raw sugar exports.
To some farmers, the response is too little, too late.
"When you lose 10,000 rupees ($156), they offer you 100 rupees. So far we haven't got any assistance," said Manik Andhale, a farmer from Kamargaon village in Maharashtra state, whose onion crop suffered rain damage.
To be sure, some of the events that have led to the crisis are beyond the government's control.
Until last year, for example, Iran paid a premium for Indian sugar, soymeal, barley and basmati rice. Now, with the easing of some Western sanctions, Iran is looking to buy elsewhere.
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Cotton exports have been hit by China's decision to abandon a stockpiling plan, while non-basmati rice shipments face headwinds after Thailand decided to run down its stockpiles.
On the other side of the world, a decline in the Brazilian real following a scandal at oil giant Petrobras last year has weighed on sugar prices, making Indian exports uncompetitive.
Meanwhile, the fall in global crude oil prices has depressed prices of grains and oilseeds used for biofuels. It also trimmed freight rates, making imports of commodities such as corn and soymeal from South America cheaper for Asian buyers.
A strong rupee - despite a fall last week – has further made India's farm exports uncompetitive and imports cheaper.
A major commodities trader has said the decline in agricultural exports could be as much as $5 billion, or nearly 20 percent, for the crop year to September, which would be the steepest on record.
In the villages, farmers struggle to understand why they are earning less.
"How come prices of all crops are going down?" asked Anil Sathe, a farmer in Kamargaon who said he has had to start working as a part-time laborer to make ends meet.