Short answers, pulled from the story.
Rice is a cereal grain and the staple food of over half of the world's population, grown particularly in Africa and Asia. It is the seed of the grass species Oryza sativa, known as Asian rice, or less commonly Oryza glaberrima, known as African rice. About 90% of world production comes from Asia.
Asian rice, Oryza sativa, was first domesticated in China around 9,000 years ago by Neolithic peoples of the Upper and Lower Yangtze. African rice, Oryza glaberrima, was domesticated independently in West Africa about 3,000 years ago. Genetic evidence indicates a single domestication event for Oryza sativa from the wild rice Oryza rufipogon.
In 2023, world production of rice reached 800 million tonnes, led by China and India with a combined 52% of the total. This placed rice third among crops by production, after sugarcane and maize. Less than 8% of rice produced is traded internationally.
The texture of rice depends on the balance of two starch components in the grain, amylose and amylopectin. Long-grain Indica rice stays intact and cooks dry and fluffy, while short-grain Japonica rice is oval and sticky and holds its shape when cooked. Medium-grain varieties such as arborio are moist and tend to cling together.
In 2022, greenhouse gas emissions from rice cultivation were estimated at 5.7 billion tonnes of CO2 equivalent, about 1.2% of total emissions. Rice produces almost half the greenhouse gas emissions from croplands and around 30% of agricultural methane emissions. The methane comes from long-term flooding, which causes anaerobic fermentation of organic matter in the soil.
Golden rice is a variety produced through genetic engineering to synthesise beta-carotene, a precursor of vitamin A, in the grain's endosperm. It is intended for parts of the world where vitamin A deficiency is prevalent. It has been opposed by anti-GMO activists, including in the Philippines, though in 2016 more than 100 Nobel laureates encouraged the use of such genetically modified organisms.
The dry grain is milled to remove its outer layers, the husk and the bran. Brown rice has only the inedible husk removed, while further milling removes the bran and germ to create successively whiter products. Parboiled rice is steamed before milling, which hardens the grain and moves some vitamins and minerals into the white part so they are retained.