Introduction to major field crops (1+1)

Aerobic Method of Rice Cultivation

In the uplands rice is grown in non-puddled fields without bunds, without irrigation, and without ponded water. The soil is aerobic throughout the growing season. Upland rice environments are very heterogeneous but a common characteristic is that water is a major limiting factor, soils are often problematic, soil erosion is frequently severe, and farmers are among the poorest, with little means to supply external inputs and the average yields are lower. In aerobic method, growing of rice in aerobic soil, but with the use of external inputs such as supplementary irrigation and fertilizers, and aiming at high yields. The target environments are lowlands where water is scare with the more favourable upland conditions.

In China, developments in this new way of growing rice started in the mid-1980s. To differentiate it from the traditional upland rice, I.R.R.I. recently coined the term ‘aerobic rice’, high yielding rice grown in non-puddled and non-flooded aerobic soil.

Lowland rice ecosystem however is increasingly threatened by water shortage. The reasons are diverse and location specific, but include decreasing sources (falling groundwater tables, silting of reservoirs), decreasing quality (chemical pollution, salinization), and increased competition from other sectors such as urban and industrial users. In Asia, more than 50 per cent of water used for irrigation is used to irrigate rice. Therefore, there is a need to decrease water use in rice production and increase its use efficiency. Aerobic rice is a new way of cultivating rice that requires less water than low land rice.

Benefits of aerobic method of rice cultivation

1. Puddling of soil is not required.
2. Nursery rising is not necessary.
3. Direct seeding in the main field and hence, transplanting of seedlings is not necessary.
4. Saving of seeds to an extent of about 80 per cent.
5. Saving of water up to 40-50 per cent.
6. More area can be brought under irrigation with the available water.
7. Labour requirement is less.
8. Soil structure is not spoiled.
9. Nitrogen use efficiency is more.
10. Fewer incidences of pests and diseases because of more aeration, sunlight and less humidity.
11. More number of productive tillers.
12. Higher yield.
13. More profit with reduced cost of cultivation.
14. Less methane production as moisture is maintained at field capacity. Hence, less effect on pollution.
15. Mosquito’s production is reduced.


Varieties
Some of varieties used for aerobic rice cultivation are Rasi, Maas 946-1, KRH-2 (hybrid), etc.