In some ways, rice may be considered a crop unique to the south, southeast and east Asian nations extending from Pakistan to Japan

By Dr. S.M. ALAM
NIA, Tandojam.
Sep 03 - 09, 2001

Rice is now one of the world's chief foods and will continue to be for the foreseeable future. Rice is intimately involved in the culture as well as the food ways and economy of many societies. The origins of rice have been debated for sometime, but the plant is of such antiquity that the precise time and place, of its first development will perhaps never be known. It is certain, however, that the domestication of rice ranks as one of the most important developments in history, for this grain has fed more people over a longer period of time than has any other crop. Cultivated rice belongs to two species, O. sativa and O glaberrima. Of the two, O. sativa is by far the more widely utilized. O. sativa is a complex group of two forms endemic to Africa and a third form. O. rufipogon, having distinctive partitions into South Asian, Chinese, Australian and American forms.

The greatest variety of such rice (O.sativa) is found in the zone of monsoonal rainfall extending from eastern India through Myanmar, Thailand, Laos, Northern Vietnam and into southern China. The earliest and most convincing archeological evidence for domestication of rice in Southeast Asia was discovered in 1966 in Korat area of Thailand, through the use of 14c testing as dating from at least 4000 BC. From an early beginning somewhere in the Asian arc, the process of diffusion has carried rice in all directions until today, it is cultivated on every continent save Antarctica. Pudding, soil and transplanting seedlings were two methods adopted for rice cultivation and farming, which remain widely practiced to this day. However, transplanting like pudding provides the farmer with the ability to better accommodate the field duration and adjusting the planting calendar. The data 2500 BC. has been mentioned for Mohenjo-Daro. Rice spread gradually to Sri Lanka, Greece, Sicily, Europe, North Africa, North America and Southern areas of North America.

Rice is produced in a wide spectrum of locations and under a variety of climatic condition ranging from the wettest areas in the world to the driest deserts: For example, if it is produced along Myanmars, Araken coast, where the growing season records an average of more than 5,100 mm of rainfall, but it is also produced at Al-Hasa Oasis in Saudi Arabia, annual rainfall is less than 100 mm. temperature condition too, vary greatly from those of the upper Sindh in Pakistan where the rice season averages 33C to 17C in Otaru, Japan. The crop is produced at sea level on coastal plains and in delta region throughout Asia to a height of 2,600 m on the slopes of Nepal's Himalaya. Also in Myanmars, Thailand and India, Egypt, Sudan, etc. Rice is the leading food in that part of the world, where population densities are highest and where farmland per capita is most severely constrained. The crop occupies an extraordinary high portion of the total planted area in south, southeast and east Asia. Southwestern Australia, Hokkaido, Spain, Italy, northern California and Nile delta are important for production of rice.

Rice as Human Food: Rice, wheat and maize are the three leading food crops in the world, together they supply directly more than 50% of all calories consumed by the entire human population. In terms of area harvested each year, wheat is the leader, with 230 million ha, followed by well land rice with roughly 145 million ha and by maize with 130 million ha. Recent world production of rough rice has stood at million tons. The consumption of rice in kg per capita per year in some rice eating countries are as (kg/capita/yr): Myanmar (186), Thailand (164), Indonesia (146), Bangladesh (130), China (114), Philippines (92), Japan (81), India (77), Brazil (51), Egypt (32), Pakistan (21), Nigeria (11), USA (9), Russia (6), South Africa (6), Mexico (5), Turkey (5) and world average is 64. Most rice is consumed in its polished state, which is low in both vitamin B. and lysine as well as poor in protein.

Rice Production: In some ways, rice may be considered a crop unique to the south, southeast and east Asian nations extending from Pakistan to Japan. Out of 26 leading rice-producing nations, 18 are located within this region, and that the rest countries outside of the region jointly produce less than 6% of world rice. In the world as a whole, rice occupies one-tenth of the arable land, while in the majority of the Asian rice arc countries, it occupies one-third or more of the total planted area. From Pakistan to Japan, rice is pre-eminent. Here, too, populations are high, and a close balance is maintained between rice production and food needs. Population and hence rice needs, are both growing rapidly.

In the years since World War-II, world rice area, yield and production have changed considerably. From 1948 to 1986, the area planted to rice increased by 67%, the mean yield obtained from that area went up by 95%, and total production more than tripled. World rice requirements are estimated to increase at the compound rate of 1.7%/yr. between 1985 and 2020. This is a rate well above the projected population growth for the same period and reflects some substitution of other foods for rice, as well as an increase in the general well-being of the world population and increased per capita consumption. For the leading rice growing countries of Asia, the needed rate of increased production is even greater - 2.1%/ yr. This means that by the year 2020, the world will need 13 million tons of additional rough rice each year. With the accelerating loss of productive rice land to rising sea levels, salinization, erosion and human settlements, the problem becomes one of the increasing yields under evermore trying circumstances. During Green Revolution onwards, the total production from Asia's 11 leading rice producing nations increased by 75%. Much of the yield increase could be traced to the introduction of the dwarfing gene and to the increased use of fertilizer and other inputs.

Rice and Population: Agricultural population densities in Asia's rice-producing lands are among the highest in the world and continue to increase at a remarkable rate. Labour demands are often highly seasonal and are frequently in rhythm with the annual monsoon. In addition, rapid population growth puts increasing pressure on the already strained food-producing resources. Population growth rates among rice-eating populations average about 1.9% annually. But, the rest of the world population is increasing less than 1.5%.

Water control and rice growth water is the most essential factor for the growth of rice crop. Unfortunately, lack of adequate water control is widespread throughout rice producing areas in developing countries. In Latin America and Africa, the condition is almost ubiquitous, and even in South and Southeast Asia, only 1/3 of the area planted to rice is irrigated lack of water when needed is probably the most widespread constraint to higher rice yields. a water shortage is highly probable at the beginning and at the end of the growing season in many rice-producing area. Yield reduction from drought at the early stages of crop growth may be relatively minor, but that from lack of water during the reproductive phase can be highly significant. Drought can affect rice in all environments, including deep-water areas. Drought stress is especially damaging to rice crops grown in the dry season, when the evaporation rate is high. Water control has a major influence over the success or failure of rice cultivation, but other climatic constraints are important as well.

Development of Modern Rice Farming: During 1950 and 1960, the rapidly growing world population caused great concern about the availability of sufficient food to forestall massive starvation On 1962, the International Rice Research Institute (IRRI was established at Manila, Philippines with the help of USA. It was an educational and research centre-dedicated and devoted principally to study and improvement of rice, the world's major food crop. Today, IRRI has grown to be a premix agricultural research centre in the world of rice breeding.

Rice yield increases and improved food availability have been particularly important in the heavily populated and developing economies extending from Korea to Pakistan. The Term Green Revolution refers to complex package of technology including both improved seeds and a wide range of management practices. The new plant types show a strong positive response to fertilizer, made possible by a high leaf area index, short stature and stiff straw that resists lodging. These plant varieties have resistance to many insect pests as well as to a wide range of plant diseases. The management package is concerned with timing, rate and method of application of various inputs, appropriate spacing of plants, thorough weeding, careful monitoring and control of pests, improved harvesting, drying and threshing methods.

Green Revolution in rice farming is in fact a green evolution. It is an ongoing process of technological innovation being developed in and applied to Third World Farm areas. Succeeding innovations led to improved grain quality, disease resistance, pest resistance, and shortened growing periods. The high yielding rice varieties developed after 1965, brought a tremendous increase in the yield on per unit area basis. On the basis of such improvement in rice production the export of rice has been increased, in addition some countries where growth of rice is not possible, they depend on the import of this item. We can see such scenarios of export and import of rice in these lines.

The estimated world rice (paddy) production in million tons for the year 2000 for Asia and Asian countries are: Asia 539.4, (Bangladesh 35.6, China 187.1, India 131.0, Indonesia 50.1, Iran 2.4, Japan 10.9, Kazakistan 0.2, Korea DPR 1.7, Korea Rep. of 1.2, Mayamar 20.6, Pakistan 6.5, Philippines 12.6, Thailand 24.0, Turkey 0.3, Vietnam 32.7, Africa 17.2 (North Africa 5.6, Egypt 5.6, Sub-Saharan Africa 11.6, Western Africa 7.6, (Nigeria 3.5, Central Africa 0.4, Southern Africa 2.7 and Madagascar 2.4); Central America 2.4 (Mexico 0.4), South America 19.7 (Argentina 0.5, Brazil 10.9 Colombia 1.8), North America 8.4 (United States 8.4), Europe 3.3 (EC 2.6, Russia Fed. 0.5, Ukraine 0.1); Ocealıia 1.8 (Australia 1.8). Thus, the total world rice (paddy) production for the year 2000 is 592.2 million tons annually (ie. developing countries 567.0 and developed countries 25.2).

Rice exports for the year 2000 recorded for different countries of the world in million tons are: Asia 16.9, China 2.6, India 1.3, Japan 0.5, Myanmar 0.2, Pakistan 1.9, Thailand 6.5, Vietnam 3.9, Africa 0.5, Egypt 0.5, South America 1.4, Argentina 0.2, Brazil 0.2, Suriname 0.1, Uruguay 0.6, North America 2.7, United States 2.7, Europe 0.2, EC 0.2, Oceania 0.7, Australia 0.7, World 22.3 (i.e. developing countries 18.3 and developed countries 4.1).