The rightwing Swiss People's Party has urged voters to say "yes" to Sunday shopping and "no" to a moratorium on genetically modified organisms (GMOs).
Party delegates meeting in Näfels, canton Glarus, voted clearly in favour of supporting the government's position for the November 27 ballot.
Citizens are to vote on whether trading hours should be extended in major railway stations and airports and if farmers should wait another five years before attempting to introduce GMOs.
The assembly turned down the GM moratorium by a two-to-one majority, convinced that consumers and farmers were responsible enough to decide if biotechnology could benefit them.
"A moratorium would prevent consumers from choosing the food they want to eat and put farmers under supervision," said parliamentarian Hansruedi Wandfluh. "It would also put our agriculture at a disadvantage because it allows for the import of GM fodder while banning its production in Switzerland.
While some party members argued that most consumers weren't interested in GM foods and defended what they called "quality agriculture," delegates preferred to toe the government line.
Wandfluh added that a moratorium would harm Swiss biotechnological research and companies.
Earlier this month, Economics Minister Joseph Deiss warned that a moratorium on GMOs in agriculture would be bad news for farmers and consumers.
Deiss said that the current law on the issue, which came into force last year, provided enough protection for people and the environment.
The present legislation is aimed at strictly controlling GMOs. It forbids the keeping of genetically modified animals in agriculture for an indefinite period, whereas the initiative foresaw five years.
Hardly any of the delegates opposed the extension of Sunday trading hours for shops in major transports centres, a modification of Switzerland's labour legislation.
The revision aims to anchor in law what already happens in larger stations and airports.
"This reform is necessary, because consumers, travellers and tourists need shops in stations and airports," said parliamentarian Peter Föhn, adding that the project would not just benefit big cities and urban areas.
Trade unions fear that moves to relax Switzerland's tough Sunday trading restrictions will eventually lead to a seven-day working week across the country.
But Föhn said that that shops in airports and railway stations offered part-time jobs that benefited people's family and professional lives. "Normally the Left would defend this kind of position," he added.
swissinfo with agencies
Delegates of the rightwing People's Party - which is often opposed to official positions, especially on Europe - have decided to follow the government line on upcoming nationwide votes.
A 330-to-257 majority said "yes" to extended Sunday trading hours for shops in major stations and airports.
229 delegates versus 109 voted against a five-year moratorium on GMOs in agriculture.