Rice is more than a staple of the Cambodian diet. It also implicates land rights, trade and international relations.
A post on The Mirror  reveals the frustration of Cambodians, including Cheam Yeap, a Cambodian People's Party official, over land leases to neighboring Vietnam. From the Mirror, citing Cheat Khmer, Vol.1, #40, 18.3.2009:
Thousands of hectares of citizen’s land lying along the Yuon [Vietnamese] border of An Giang Province, bordering Svay Rieng and Prey Veng, are being leased to Yuon companies by Khmer authorities along the Yuon border to grow agro-industry crops. The Phnom Penh Post published an article on 26 February 2009, quoting the Svay Rieng governor, Mr. Cheang Am, that 10,000 hectares of land in Svay Rieng are prepared to be leased to Yuon companies along the border and also, the Prey Veng governor, Mr. Ung Samy, told the Phnom Penh Post that he will discuss with Yuon officials in Yuon [Vietnam] about the leasing of rice fields along the border to Yuon companies to come to do rice cultivation in Khmer territory.
Yeap is concerned the leases will evolve into ownership changes, resulting in a reduction of Cambodian territory. Others, like Prum Soanara, an engineer, thinks the land is best utilized if given to the country's own citizens to cultivate rice.
KI Media  highlights the problem of illegally imported rice with an article from the Nation:
The Thai Rice Exporters’ Association and the Board of Trade of Thailand (BoT) will soon propose that the Commerce Ministry set up a Public Warehouse Organisation as an “import agency” to oversee rice imports once the Asean Free Trade Area (Afta) eliminates all import tariffs.
The agency would institute measures to protect Thai farmers, such as requiring imported rice only be used for raw purposes in manufacturing. However, exporters are worried such protections encourage those seeking to manipulate the system, thereby increasing the amount of illegally traded rice, including rice grown in Cambodia.
In addition to its practical roles, rice is symbolic of Cambodian culture, as this video shows. This piece from Khmer Civilization  involves images of rice from farm to market:
The thumbnail image used is from the Flickr page of Nohch