Over the centuries, three main types of rice had developed in Asia, depending on the amylose content of the grain. They were called indica (high in amylose and cooking to fluffy grains to be eaten with the fingers), japonica (low in amylase and cooking to sticky masses suitable for eating as clumps with chopsticks), and javanica (intermediate amylose content and stickiness). Rice is further divided into long, medium and short-grained varieties, and in the sub-continent different regions grow and consume different varieties. Basmati rice is probably the best-known variety of rice from the sub-continent. Basmati denotes 'queen of fragrance' and this fragrant rice is chiefly grown and exported by Pakistan and India. The dominant food crop in Bangladesh is rice which accounts for at least 70 of the land under agriculture. The best varieties are rice grown in shallow, slowly moving water and so irrigation is crucial to the success of rice-growing in the sub-continent. Slash and burn methods of creating rice fields in some parts of India have placed tremendous pressures on the environment.