Rainfed rice - IRRI books - International Rice Research Institute

Influence of High-Quality Seeds on Rainfed Upland Rice Yield
Constraints to rice production in red and lateritic soils
Because of environment, farmers usually cultivate local seed varieties with
low-cost traditional methods. The yields of these varieties are very poor.
The specific constraints are as follows:
Intermittent soil moisture stress due to erratic distribution of rainfall and
poor moisture-holding capacity of the soil
Heavy weed infestation
Loss of applied nitrogen due to runoff and deep percolation
Nutrient stress in the soil (nutrient deficiencies, toxicities and adverse soil
pH)
Uneven germination due to quick disappearance of soil moisture, leading
to poor crop stand and poor soil fertility, resulting in poor crop growth
and low panicle density and grain number per panicle
Farmers’ apathy to adopting modern technology due to economic
backwardness and lack of knowledge
Impact of high-quality
seeds
Technologies for boosting production
in this ecosystem are available.
Among these, replacement of
farmers’ seeds with improved ones is
the least costly. Adoption of
improved seed was therefore
considered as an important impact
point in the pilot project.
Improved varieties used
in the demonstrations
Bunded fields
Bhupen
Annada
IET – 12029
Unbunded fields
Heera
BG – 367-4-1
BG – 367-7-1
Yield of transplanted rice as influenced by high-
About 53 direct-seeded quality improved seed in field demonstrations
demonstrations in an unbunded during 1992-95 in rainfed uplands of four West
situation and 110 transplanted Bengal districts
demonstrations in a bunded
situation were laid out in the four
districts. The control in both types of
demonstrations was the farmers’
local seed. The demonstration fields,
including the control, were under
the same management.
Use of high-quality seeds alone
can ensure yield advantage of 5.6-
7.6 q/ha in bunded transplanted
fields on red and lateritic soils.
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