Jubilee supporters on Sunday briefly disrupted NASA's rally in Kapsabet grounds, Nandi.
Police had to intervene to repulse the youths chanting anti-Raila slogans.
NASA principals led by Raila Odinga said the youths had been paid to cause chaos.
The rally, however, continued despite the heavy rain in the area.
Raila accused the Jubilee administration of failing to address the challenges facing farmers in the country.
" Since Jubilee took over, farmers have become poorer. The prices of raw milk have gone too low while tea farmers now get only Sh10 per Kilo as a bonus, this is a big failure of the government," Raila said.
Raila who is NASA'S presidential candidate told the residents that the opposition is determined to improve Kenya’s agricultural sector.
"We decided to start our rallies here because we know the significance of this town, this is the headquarters of the Kalenjin community," he said.
The NASA's brigade included Raila's running mate and Wiper leader Kalonzo Musyoka, Musalia Mudavadi, Moses Wetang'ula and Bomet Governor Isaac Rutto.
Kalonzo said the opposition is assured of big support in the Rift Valley, despite the region being Deputy President William Ruto's backyard.
ANC leader Musalia Mudavadi asked the police to ensure that political campaigns are safe and arrest leaders propagating violence.
Wetang’ula asked youth not to be misused by leaders to cause violence.
Rutto, who is the leader of
Chama Cha Mashinani said the Jubilee administration had failed to fulfill their 2013 pre-election
promises.
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