Rainfed rice - IRRI books - International Rice Research Institute

RAINFED RICE A SOURCEBOOK OF BEST PRACTICES AND STRATEGIES IN EASTERN INDIA
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Upland
Rice in the upland ecosystem is
grown in rainfed bunded or
unbunded fields, with naturally
well-drained soils, without any
surface water accumulation.
The upland rice ecosystem is
characterised by extreme diversity of
soils and topography that ranges
from sloping, terraced lands to well-
drained flatlands. Traditional
germplasm and its associated
farming practices add to the system
diversity. It is marked by varying
degrees of degradation and has low
and variable productivity.
Rainfed lowland ecosystems
Rainfed shallow, favourable
Rainfed shallow, drought-prone
Rainfed shallow, drought- and
submergence-prone
Rainfed shallow, submergence-prone
Rainfed medium deep, waterlogged
Upland ecosystem
Favourable upland with long growing
season (>110 days)
Favourable upland with short growing
season (90-110 days)
Unfavourable upland with long growing
season
Unfavourable upland with short growing
season
Rainfed lowland
Rice in this ecosystem is grown in
bunded fields that are flooded for at
least part of the season at a water
depth that does not exceed 50 cm for
more than 10 consecutive days.
Fields are not irrigated but may have
on-farm rainwater conservation
facilities.
Any or a combination of drought, flooding and adverse soils constrains the
adoption of high-yielding cultivars and use of high-input levels in this
ecosystem. The rainfed lowlands do not encompass a homogeneous class of
ricelands. They include a large array of unique physical environments.