By Aaron Maasho

ADDIS ABABA, Sept 2 (Reuters) - At least seven foreign-owned flower farms in Ethiopia's Amhara region have been burnt to the ground or partially damaged in political violence afflicting the country over the past two months, producers said on Friday.

Anti-government protests over disputed provincial boundaries and allegations of human rights violations have spread in the north-central province, the second region to be riven by turmoil this year alongside Oromiya province in central Ethiopia.

In June, Human Rights Watch said security forces killed at least 400 people in Oromiya protesting at government plans to incorporate some parts of the region within the city limits of the capital Addis Ababa.

"Around seven flower farms have been affected - some burnt to the ground, others partially vandalised during attacks that took place Monday to Wednesday," the Ethiopian Horticultural Producers and Exporters Association said in a statement emailed to Reuters. No injuries have been reported from the attacks.

The list of firms included Esmeralda Farms BV of the Netherlands, Italian owned-Alfano Fiori, Indian firm Fontana Flowers PLC, and others operated and owned by investors from Israel, Belgium and the Middle East, it added.

All plots are close to Bahir Dar, the Amhara regional capital. "Details are still being gathered. The scope of damage requires further investigation," the statement said.

Tensions have been rumbling for two decades over the status of Wolkayt district, a stretch of land that protesters from Amhara say was illegally incorporated into the neighbouring Tigray region to the north.

Though demonstrators have behaved mainly peacefully, there have been incidents where government officials and civilians perceived to be associated with the government have been attacked by protesters.

A spokeswoman for Flora Holland, the world's largest flower auction based in the Dutch city of Aalsmeer, said that growers were assessing the damage from the attacks.

"The scope of the damage differs greatly from business to business," Elizabeth Palandeng said, but she did not believe it would lead to a long-term problem with deliveries.

Hardest hit appeared to be a Dutch company, Esmeralda, which said in a statement that 10 million euros worth of investments "went up in smoke" in an attack on its farm on Sept. 29.

The African flower industry has grown quickly in recent years, with Kenya and Ethiopia together providing about 65 percent of the Dutch auction's total.

Any sign of unrest is closely watched in Ethiopia, an important Horn of Africa ally of the West against Islamist militants in neighbouring Somalia, and an economic power seen as a centre of relative stability in a combustible region.

Earlier this week, Ethiopian Prime Minister Hailemariam Desalegn said his administration would carry out "deep-rooted" reforms and pledged to address grievances, though he warned of measures if protests escalated into violence.

(Additional reporting by Toby Sterling; editing by Elias Biryabarema and Mark Heinrich)