Rainfed rice - IRRI books - International Rice Research Institute

Identification of Donors
for Rice Breeding
T
he total rice area in India is 42.3 million ha, of which about 63.3%
(26.8 million ha) is under rainfed cultivation. Rice area in eastern
India, comprising the states of Assam, Bihar, Orissa, West Bengal,
eastern Madhya Pradesh, and eastern Uttar Pradesh, is 26.8 million ha (i.e.,
63.3% of the total rice area). About 21.3 million ha (79.5%) of this area is
rainfed, of which 4.3 million ha is rainfed uplands, 12.9 million ha is rainfed
lowlands and 4.1 million ha is under deepwater situations. Rice productivity
in these lands is low. Yield potential of locally adapted, low-yielding, stresstolerant
varieties is improved genetically by hybridisation and selection.
These cultivars are the storehouse of useful genes, and are used as donors in
breeding programs.
Rainfed ecosystems and
plant types
Uplands
FAVOURABLE UPLANDS
High rainfall zone, bunded, fertile
soil
Plant type needed: semi-dwarf/
semi-tall
UNFAVOURABLE UPLANDS
Low rainfall zone, without bunds,
poor soil
Plant type needed: semi-tall
Lowlands
FAVOURABLE LOWLANDS
Shallow with 0-30 cm water depth
Plant type needed: semi-dwarf/
intermediate dwarf
UNFAVOURABLE LOWLANDS
Semi-deep situation (flash-flood)
(water depth is 30-50 cm)
Plant type needed: semi-tall
Rice yields in eastern India
Rainfed uplands 0.6-1.5 t/ha
Rainfed lowlands 0.9-2.4 t/ha
Irrigated lands 3.2 t/ha
Eastern India (average) 1.43 t/ha
National average 1.91 t/ha
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